Статті в журналах з теми "Bio-Sourced composite material"

The gradual development of government policies for ecological transition in the modern construction sector leads researchers to explore new alternative and low environmental impact materials with a particular focus on bio-sourced materials. In this perspective, the mechanical, thermal insulation, and the sound absorption performances of a spent coffee grounds/potato starch bio-based composite were analyzed for potential application in buildings. Based on thermal conductivity and diffusivity tests, the coffee grounds waste biocomposite was characterized as an insulating material comparable with conventional thermal insulation materials of plant origin. Acoustical tests revealed absorption coefficients in the same range as other conventional materials used in building acoustical comfort. This bio-sourced material presented a sufficient compressive mechanical behavior for non-load-bearing structures and a sufficient mechanical capacity to be shaped into building bricks. Mechanical, thermal, and acoustic performances depend on the moisture environment. The groundwork was laid for an initial reflection on how this composite would behave in two opposite climates: the continental climate of Reims in France and the tropical climate of Belém in Brazil.

Research has recently transitioned from the study of fossil-based materials to bio-sourced ones, following the quest to achieve sustainability. However, fire presents a unique hazard to bio-composite materials, which limits their applicability in various sectors. This necessitates an in-depth assessment of the fire behaviour of biobased composites used for specific applications. Improving the fire properties of bio-composites with flame retardants tends to reduce mechanical strength. Therefore, this review focused on biobased composite materials for packaging, structural, automotive, and aeronautical applications that are both mechanically strong and fire safe. It was noticed that the interfacial bonding between the matrix and the reinforcement should be optimized. In addition, optimum amounts of flame retardants are required for better fire performance. This article covers flame retardants for biobased composites, the optimum amount required, and the extent of improvement to the thermal stability and flammability of the materials. This research will help material scientists and the like in their selection of biomass feedstock, flame retardants, and general materials for different types of applications.

Abstract The main objective of this paper aims at investigating the potential use of sisal yarn into composite material despite the inherent variability of properties of natural resources. A multi-scale approach of the behavior of sisal fiber woven reinforcements is conducted to understand and evaluate the different properties of woven reinforcements. At the yarn scale, a piezo-resistive sensor yarn was developed to assess deformations and stress concentrations in-situ in order to understand the material behavior during the weaving of woven reinforcements fibrous for bio-sourced composite materials. At the fabric scale, 2D woven reinforcements are developed based on a conventional weaving process. The production and characterization of composite sheets based on 2D woven reinforcements show the potential of sisal fiber woven reinforcements compared to natural fiber woven reinforcements from literature.

It is well-known that energy consumption is increasing around the world on a daily basis. In the construction sector, a highly effective solution for reducing energy consumption involves exploring both modern and traditional buildings designed to adapt to climate changes. One promising approach is to use paper waste and bio-sourced materials as the basis for insulation. The purpose of this study was to improve the sustainability of buildings by using recycled waste materials that have a positive impact on the environment, people, and the economy. A novel insulating material composed of recycled paper waste and Ampelodesmos mauritanicus leaves and fibers was developed and used in non-load-bearing elements. The paper waste was transformed into pulp and mixed with the bio-sourced materials to create a composite material that exhibits excellent insulation properties. The resulting material is lightweight, durable, and cost-effective. Furthermore, different mechanical and thermal analyses were performed on specimens with varying dosage ratios. The results showed that the developed material has good thermal insulation, with a value of 0.027 W/m.K.

The purpose of this study is to evaluate the potential of bio-sourced material based on cereal straw for an efficient insulation. Decreasing significantly energy consumption of buildings requires not only the very best insulation material for heat loss reduction through the wall but also the reduction of air permeability which can affect automatically the comfort in the building. This is why, propose an insulation material with low thermal conductivity remains insufficient and the evaluation of the performance of the new insulation material in situ in real conditions is an essential step. The experimental building ( PROMETHE demonstrator) is set up with wood frame and multilayered walls composed with cinder blocks and insulation bio-composite based on cereal straw in order to simulate the thermal rehabilitation conditions according the External thermal insulation principle. Each façade is divided in four part with three different insulation bio-composites and naked part for comparison reasons. Hygrothermal sensors are used both inside and outside of the demonstrator, and heat-flux sensor is placed at the cinder blocks biocomposite interface. These in situ measurements are used to compare the efficiency of three bi-sourced materials and for the modeling the hygrothermal behavior of the multilayer wall by using the set of identified parameters in laboratory.

This paper presents the work carried out as part of a study of a proactive interior coating based on both plaster and a phase change material (PCM), intended to improve the energy efficiency of buildings. This bio-based PCM is composed of a mixture of vegetable oils, methyl stearate, and methyl palmitate micro-encapsulated into polymer capsules. These components with distinct thermal properties constitute a mixture that displays supercooling and proves difficult to characterize using methods known in the literature. This article focuses on the thermophysical characterization (i.e., thermal conductivities, thermal capacities, latent heat, melting temperatures) and numerical modeling of a sample of this coating tested in the laboratory. This characterization is derived from experimental measurements carried out on a fluxmeter bench and by inverse methods. A new model of PCM composite characterization is presented and simulated using Python; the output shows a high degree of accuracy in describing the thermal behavior of the coating, regardless of the thermal stress applied, even making it possible to represent the phenomenon of supercooling or partial melting/solidification.

The complete flax stem, which contains shives and technical fibres, has the potential to reduce the cost, energy consumption and environmental impacts of the composite production process if used directly as reinforcement in a polymer matrix. Earlier studies have utilised flax stem as reinforcement in non-bio-based and non-biodegradable matrices not completely exploiting the bio-sourced and biodegradable nature of flax. We investigated the potential of using flax stem as reinforcement in a polylactic acid (PLA) matrix to produce a lightweight, fully bio-based composite with improved mechanical properties. Furthermore, we developed a mathematical approach to predict the material stiffness of the full composite part produced by the injection moulding process, considering a three-phase micromechanical model, where the effects of local orientations are accounted. Injection moulded plates with a flax content of up to 20 V% were fabricated to study the effect of flax shives and full straw flax on the mechanical properties of the material. A 62% increase in longitudinal stiffness was obtained, resulting in a 10% higher specific stiffness, compared to a short glass fibre-reinforced reference composite. Moreover, the anisotropy ratio of the flax-reinforced composite was 21% lower, compared to the short glass fibre material. This lower anisotropy ratio is attributed to the presence of the flax shives. Considering the fibre orientation in the injection moulded plates predicted with Moldflow simulations, a high agreement between experimental and predicted stiffness data was obtained. The use of flax stems as polymer reinforcement provides an alternative to the use of short technical fibres that require intensive extraction and purification steps and are known to be cumbersome to feed to the compounder.

This paper describes the influence of seawater ageing on composites used in a range of marine structures, from boats to tidal turbines. Accounting for environmental degradation is an essential element in the multi-scale modelling of composite materials but it requires reliable test data input. The traditional approach to account for ageing effects, based on testing samples after immersion for different periods, is evolving towards coupled studies involving strong interactions between water diffusion and mechanical loading. These can provide a more realistic estimation of long-term behaviour but still require some form of acceleration if useful data, for 20 year lifetimes or more, are to be obtained in a reasonable time. In order to validate extrapolations from short to long times, it is essential to understand the degradation mechanisms, so both physico-chemical and mechanical test data are required. Examples of results from some current studies on more environmentally friendly materials including bio-sourced composites will be described first. Then a case study for renewable marine energy applications will be discussed. In both cases, studies were performed first on coupons at the material level, then during structural testing and analysis of large components, in order to evaluate their long-term behaviour. This article is part of the themed issue ‘Multiscale modelling of the structural integrity of composite materials’.

This study aimed to investigate the effect of raw waste pine wood dust (Pinus sylvestris) from furniture production on polysaccharide biopolymer film properties. The obtained biocomposite films produced via the casting method were prepared with 20% glycerol and 0%, 5%, 10%, 15%, 20%, and 25% of added wood dust in relation to the dry starch matter. Wood dust composition and particle size distribution analysis were performed. In order to evaluate the material surface properties, tests were carried out using an atomic force microscope (AFM) and a contact angle goniometer. Utilising uniaxial tensile test methodology, the values for both tensile strength and Young’s modulus were determined. In addition, the barrier properties, water solubility index, and colour were also investigated. The research showed that wood dust affected the functional parameters of the obtained biocomposites. A wood dust content increase causes the Young’s modulus value to rise with a progressive decrease in the max. strain. The filler did not change the films’ wetting properties, and each had a hydrophilic surface regardless of the additive amount. The bio-sourced composites obtained were non-toxic and environmentally neutral materials, suitable to be applied in the packaging industry as well as the agriculture sector.

This work emphasizes an innovative approach utilizing 3D imaging technology based on synchrotron radiation to assess the microstructure of second-phase iron particles and the porous structure within 3D-printed PLA/magnetic iron composites at different printing angles. The study examines how these observations relate to the material’s ductility when processed using fused filament fabrication. In particular, this study examines the impact of one processing parameter, specifically the printing angle, on the microstructure and mechanical behaviour of a polylactic acid (PLA)–iron (PLI) composite designed for magnetic actuation. Fused filament fabrication is employed to produce PLI tensile specimens, with varied printing angles to create different layups. X-ray microtomography is utilized to analyse the microstructure, while tensile mechanical properties are evaluated for all composites, with findings discussed in relation to printing angle conditions. Scanning Electron Microscopy is used to examine the fractography of broken specimens. Results indicate that the printing angle significantly influences the tensile properties and mechanical anisotropy of 3D-printed PLI composites, with an optimal 45°/45° layup enhancing tensile performance. These findings suggest that 3D-printed PLI composites offer a cost-efficient means of producing bio-sourced, light-adaptive materials with intricate magnetic actuation capabilities. By quantifying the modulation of mechanical properties based on printing parameters that influence microstructural arrangement, the research sheds light on a novel aspect of composite material characterization.

The industrial demand for functional filaments made of bio-sourced, biocompatible, biodegradable, and/or recyclable polymers and composites for material extrusion (MEX) 3D printing is continuously growing. Polylactic acid (PLA), the most popular filament, combines such properties, yet its reinforcement with low-cost, inert, and/or recycled fillers remains challenging. Herein, glass in three different micro/nano-forms was the reinforcement agent in PLA. Three different experimental tiers were elaborated by producing composite filaments with glass in powder, beads, and flake forms in various loadings to optimize the concentrations. A thermomechanical process, i.e., melt filament extrusion, was exploited. The composites were evaluated for their thermal degradation stability and composition using thermogravimetric analysis and Raman. MEX 3D printing was used to produce tensile, flexural, impact, and microhardness specimens, to quantitatively evaluate their mechanical response. Field emission scanning electron microscopy evaluation and fractography were carried out to depict fracture patterns of the specimens after their tests. All three glass types induced impressive reinforcement effects (up to 60% in flexural loading), especially in the flake form. The impact of the additional process cost through glass fillers implementation was also assessed, indicating that such composites are cost-effective.

In the presented work, poly(3-hydroxybutyrate)-PHB-based composites for 3D printing as bio-sourced and biodegradable alternatives to synthetic plastics are characterized. The PHB matrix was modified by polylactide (PLA) and plasticized by tributyl citrate. Kaolin particles were used as a filler. The mathematical method “Design of Experiment” (DoE) was used to create a matrix of samples for further evaluation. Firstly, the optimal printing temperature of the first and upper layers was determined. Secondly, the 3D printed samples were tested with regards to the warping during the 3D printing. Testing specimens were prepared using the determined optimal printing conditions to measure the tensile properties, impact strength, and heat deflection temperature (HDT) of the samples. The results describe the effect of adding individual components (PHB, PLA, plasticizer, and filler) in the prepared composite sample on the resulting material properties. Two composite samples were prepared based on the theoretical results of DoE (one with the maximum printability and one with the maximum HDT) to compare them with the real data measured. The tests of these two composite samples showed 25% lower warping and 8.9% higher HDT than was expected by the theory.

Background: There is a considerable demand for lower limb prostheses globally due to vascular disease, war, conflict, land mines and natural disasters. Conventional composite materials used for prosthetic limb sockets include acrylic resins, glass and carbon fibres, which produce harmful gasses and dust in their manufacture.Objectives: To investigate the feasibility of using a renewable plant oil-based polycarbonate-polyurethane copolymer resin and plant fibre composite, instead of conventional materials, to improve safety and accessibility of prosthetic limb manufacture.Study Design: Experimental, bench research.Methods: Test pieces of the resin with a range of plant fibres (10.0% by volume) were prepared and tensile strengths were tested. Test sockets of both conventional composite materials and plant resin with plant fibres were constructed and tested to destruction.Results: Combinations of plant resin and either banana or ramie fibres gave high tensile strengths. The conventional composite material socket and plant resin with ramie composite socket failed at a similar loading, exceeding the ISO 10328 standard. Both wall thickness and fibre-matrix adhesion played a significant role in socket strength.Conclusions: From this limited study we conclude that the plant resin and ramie fibre composite socket has the potential to replace the standard layup. Further mechanical and biocompatibility testing as well as a full economic analysis is required.Clinical relevanceUsing readily sourced and renewable natural fibres and a low-volatile bio-resin has potential to reduce harm to those involved in the manufacture of artificial limb sockets, without compromising socket strength and benefitting clinicians working in poorer countries where safety equipment is scarce. Such composite materials will reduce environmental impact.

The key drivers of the growing interest in the recovery of local materials, particularly land and waste plants, are low-cost building materials, thermal comfort, decreased energy consumption, and decreased carbon dioxide polluting emissions. This work's primary objective is to test a bio-sourced composite material that takes the form of a block of unfinished soil that has been stabilized with cement and blended with wheat straw. This study is being done with the objective of examining the impact of this fiber at different weight percentages (0, 2, 3%, and 4%) on the mechanical behavior, durability, and thermophysical properties of the produced blocks. The results obtained indicated an increase in thermal conductivity, from 2.75 W/mK for the blocks without wheat straw fiber to 0.398 W/mK for those getting 4% of the wheat straw fiber, signifying an improvement in thermal insulation. While retaining the low performance threshold required by the earth construction standard, this improvement was accompanied by an average decrease in mechanical performance.

The demand for bio-sourced materials is currently increasing. Cork material because of its unique properties (fire resistant, energy absorbing, …) is then an excellent candidate for a large set of applications. In order to widen its possible uses, cork agglomerates with reinforcements at a 0.48 density were studied to compare their mechanical performances with classical cork agglomerates. This paper investigates the effect of these foreign reinforcements on the properties of agglomerated cork under a compressive loading. The material behavior has been determined as a function of the average strain rate and the direction of solicitation. The microstructure was first observed through optical and scanning electronic microscopy, spotting charges between each cork bead. The characterisation of cork at different strain rates was then carried out. An electromechanical testing machine was used to apply an uniaxial compression at quasi-static strain rates. Reinforced agglomerated cork was found to be anisotropic and strain-rate dependant. Its micro-structure reveals at complex composite material influencing strongly mechanical properties. Both Young's modulus and absorbed energy density at 0.6 strain increase with the cross-head speed displacement. From 12.7 MPa and 0.77 J.mm-3 when compressed at 0.05 mm·min-1 to 19.9 MPa and 1.44 J·mm-3 at 500mm·min-1 in the Off-plane direction.

HKUST-1 is a metal-organic framework (MOF) that is widely studied as an adsorbent for CO2 capture because of its high adsorption capacity and good CO2/CH4 selectivity. However, the numerous synthesis routes for HKUST-1 often result in the obtention of MOF in powder form, which limits its application in industry. Here, we report the shaping of HKUST-1 powder via the extrusion method with the usage of bio-sourced polylactic acid (PLA) as a binder. The characterization of the composite was determined by XRD, FTIR, TGA and SEM analyses. The specific surface area was determined from the N2 adsorption isotherm, whereas the gas adsorption capacities were investigated via measurements of CO2 and CH4 isotherms of up to 10 bar at ambient temperature. The material characterization reveals that the composite preserves HKUST-1’s crystalline structure, morphology and textural properties. Furthermore, CO2 and CH4 adsorption isotherms show that there is no degradation of gravimetric gas adsorption capacity after shaping and the composite yields a similar isosteric adsorption heat as pristine HKUST-1 powder. However, some trade-offs could be observed, as the composite exhibits a lower bulk density than pristine HKUST-1 powder and PLA has no impact on pristine HKUST-1’s moisture stability. Overall, this study demonstrates the possibility of shaping commercial HKUST-1 powder, using PLA as a binder, into a larger solid-state-form adsorbent that is suitable for the separation of CO2 from CH4 with a well-preserved pristine MOF gas-adsorption performance.

Natural bio-based insulation materials have been the most interesting products for good performance and low carbon emissions, becoming widely recognized for their sustainability in the context of climate change and the environmental impact of the building industry. The main objective of this study is to characterize a new bio-sourced insulation material composed of fibers and an adhesive based on cornstarch. This innovative material is developed from waste of the marine plant called Posidonia oceanica (PO), abundantly found along the Algerian coastline. The research aims to valorize this PO waste by using it as raw material to create this novel material. Four samples with different volumetric adhesive fractions (15%, 20%, 25%, and 30%) were prepared and tested. The collected fractions underwent a series of characterizations to evaluate their properties. The key characteristics studied include density, thermal conductivity, and specific heat. The results obtained for the thermal conductivity of the different composites range between 0.052 and 0.067 W.m−1.K−1. In addition, the findings for thermal diffusivity and specific heat are similar to those reported in the scientific literature. However, the capillary absorption of the material is slightly lower, which indicates that the developed bio-sourced material exhibits interesting thermal performance, justifying its suitability for use in building insulation in Algeria.

Exploitation of Nigerian bentonitic clay deposit will offer economic advantage in terms of utilization for drilling purpose and prevent money spent on importation. Clay used for this analysis was beneficiated using sodium Carbonate (Na2CO3) and the change in the elemental composition of the raw clay sample and treated clay with was estimated using X-ray fluorescence spectroscopy (XRF). The treated clay and locally sourced bio-materials were added to the formulation of drilling fluid using Reduced Central Composite Design (RCCD). The fluid loss and cake thickness of prepared drilling fluid were determined using filter loss test kit. The result of the investigation show that the maximum recorded fluid loss was 14.4 ml/30mins at 100 psi while cake thickness values improved with addition of the bio-materials to the drilling fluid formulation when compared with the standard values.

Biological molecules can be obtained from natural sources or from commercial waste streams and can serve as effective feedstocks for a wide range of polymer products. From foams to epoxies and composites to bulk plastics, biomolecules show processability, thermal stability, and mechanical adaptations to fulfill current material requirements. This paper summarizes the known bio-sourced (or bio-derived), environmentally safe, thermo-oxidative, and flame retardant (BEST-FR) additives from animal tissues, plant fibers, food waste, and other natural resources. The flammability, flame retardance, and—where available—effects on polymer matrix’s mechanical properties of these materials will be presented. Their method of incorporation into the matrix, and the matrices for which the BEST-FR should be applicable will also be made known if reported. Lastly, a review on terminology and testing methodology is provided with comments on future developments in the field.

Composite materials containing natural reinforcement fibers, generally called biocomposites, have attracted the interest of both researchers and manufacturers, but the most environmentally advantageous combinations include a bio-based matrix, as well. With this in mind, a poly(lactic acid) (PLA) matrix was reinforced with natural fibers from hemp, both untreated strands (UHSs) and soda-bleached fibers (SBHFs). The preparation of the subsequent fully bio-sourced, discontinuously reinforced composites involved kinetic mixing, intensive single-screw extrusion, milling, and injection molding. Up to a fiber content of 30 wt%, the tensile modulus increased linearly with the volume fraction of the dispersed phase. Differences between SBHFs (up to 7.6 Gpa) and UHSs (up to 6.9 Gpa) were hardly significant (p = 0.1), but SBHF-reinforced composites displayed higher strain at failure. In any case, for the same fiber load (30 wt%), the Young’s modulus of PLA/hemp biocomposites was greater than that of glass fiber (GF)-reinforced polypropylene (5.7 GPa), albeit lower than that of PLA/GF (9.8 GPa). Considering all the measurements, the contribution of each phase was analyzed by applying the Hirsch model and the Tsai-Pagano model. As a concluding remark, although the intrinsic tensile modulus of SBHFs was lower than that of GF, the efficiency of those natural fibers as reinforcement (according to the rule of mixtures) was found to be higher.

Over the last two decades, bio-polymer fibers have attracted attention for their uses in gene therapy, tissue engineering, wound-healing, and controlled drug delivery. The most commonly used bio-polymers are bio-sourced synthetic polymers such as poly (glycolic acid), poly (lactic acid), poly (e-caprolactone), copolymers of polyglycolide and poly (3-hydroxybutyrate), and natural polymers such as chitosan, soy protein, and alginate. Among all of the bio-polymer fibers, alginate is endowed with its ease of sol–gel transformation, remarkable ion exchange properties, and acid stability. Blending alginate fibers with a wide range of other materials has certainly opened many new opportunities for applications. This paper presents an overview on the modification of alginate fibers with nano-particles, adhesive peptides, and natural or synthetic polymers, in order to enhance their properties. The application of alginate fibers in several areas such as cosmetics, sensors, drug delivery, tissue engineering, and water treatment are investigated. The first section is a brief theoretical background regarding the definition, the source, and the structure of alginate. The second part deals with the physico-chemical, structural, and biological properties of alginate bio-polymers. The third part presents the spinning techniques and the effects of the process and solution parameters on the thermo-mechanical and physico-chemical properties of alginate fibers. Then, the fourth part presents the additives used as fillers in order to improve the properties of alginate fibers. Finally, the last section covers the practical applications of alginate composite fibers.

In this paper, the low-energy impact behavior of a fully biobased composite made of bio-sourced polyamide 11 resin reinforced with flax fibers was investigated. Different composite laminates were studied in order to determine the stacking sequence effects on the impact behavior of these composites. Four stacking sequences were manufactured: unidirectional [0°]8, cross-ply [0°/90°]2s, sandwich-like [02°/902°]s and quasi-isotropic [45°/0/−45°/90°]s. A low impact energy of 3.6 J was applied on these laminates by means of a drop weight impact tower. The impact properties of these lay-ups were ascertained by analysing the impact load history, the maximal displacement of the impactor and the absorbed energy. Damage after impact was further assessed by visual inspections, topographic measurements, C-scan and X-ray micro-tomography observations. The results show that impact damage of composite plates is highly influenced by fiber orientation. The impact test data are in good agreement with damage analysis after impact and indicate that stacking plies in the same orientation lead to a larger induced damage, which is responsible for energy dissipation. The quasi-isotropic composite has the smallest induced damage and the highest peak load. Otherwise, the sandwich-like sequence shows the lowest peak load, the highest energy absorption and significant induced damage. Therefore, it is necessary to choose the most suitable lay-up, in terms of impact behavior, for each considered industrial application.

Pineapple materials sourced from agricultural waste have been employed to process novel bio-degradable rigid composite foams. The matrix for the foam consisted of starch extracted from pineapple stem, known for its high amylose content, while the filler comprised non-fibrous cellulosic materials sourced from pineapple leaf. In contrast to traditional methods that involve preparing a batter, this study adopted a unique approach where the starch gel containing glycerol were first formed using a household microwave oven, followed by blending the filler into the gel using a two-roll mill. The resulting mixture was then foamed at 160 °C using a compression molding machine. The foams displayed densities ranging from 0.43–0.51 g/cm3 and exhibited a highly amorphous structure. Notably, the foams demonstrated an equilibrium moisture content of approximately 8–10% and the ability to absorb 150–200% of their own weight without disintegration. Flexural strengths ranged from 1.5–4.5 MPa, varying with the filler and glycerol contents. Biodegradability tests using a soil burial method revealed complete disintegration of the foam into particles measuring 1 mm or smaller within 15 days. Moreover, to showcase practical applications, an environmentally friendly single-use foam tray was fabricated. This novel method, involving gel formation followed by filler blending, sets it apart from previous works. The findings highlight the potential of pineapple waste materials for producing sustainable bio-degradable foams with desirable properties and contribute to the field of sustainable materials.

This work aims to investigate the physical and mechanical properties of sisal fiber and yarn of Moroccan origin. The cellulosic and non-cellulosic constituents of the Moroccan sisal fiber were identified by FTIR spectroscopy. The thermal properties were studied by thermogravimetric analysis. The hydrophilicity of the fiber was evaluated by the contact angle. The results show that the sisal fiber has a low thermal stability. The mechanical properties of the fiber analyzed by the Impregnated Fiber Bundle Test (IFBT) method show that the porosity of the impregnated yarns and the twist angle of the yarns influence the elastic modulus of the sisal fiber. The physical and mechanical properties of the manufactured sisal yarns were also characterized and analyzed. The obtained results reveal an interesting potential to use the Moroccan sisal fiber in development of bio-sourced composite materials.

This research addresses environmental concerns by exploring environmentally friendly composite materials as substitutes for non-biodegradable synthetic fibers. The study proposes the development of polymer matrix composites reinforced with natural fique fibers, sourced from a plant cultivated in Colombia. A BioPoxy 36 polymer matrix with a high carbon content was used and reinforced with fique fabric using the vacuum-assisted lamination method. To improve the adhesion between the fibers and the matrix, an alkaline chemical treatment was applied to the fiber using 2% sodium hydroxide by weight. Mechanical properties were assessed through ASTM D3039 tensile and ASTM D3479 fatigue tests. A fractographic analysis was also conducted to identify the different modes of failure present. In terms of material degradation, distinct stages were observed, characterized by stiffness loss and loss factor indicators. The Coffin-Manson model was used to obtain the strain life curve for R = 0.1, using these factors as criteria. The static properties of the composite reinforced with fique fibers indicate an increase of 45% in ultimate strength, 145% in strain, and 27% in Young's modulus compared to the unreinforced matrix. In terms of dynamic properties, the elastic modulus showed a maximum variation of up to 7.88%. Electron microscopy reveals the failure mechanism, a distinct separation between the matrix and the fiber can be observed as a result of mechanical stress. The analysis reveals the brittle fracture of the hard fique fiber and some matrix separation, as well as possible fractured bubbles that may have occurred during the manufacturing process.

Pine wood sourced from pellet packaging, being abundant, holds potential for utilization in creating bio composites, particularly as activated carbon for laminated coatings in structural applications. However, there is a current lack of research identifying its specific properties as a coating material for Fiber Reinforced Polymer (FRP) composites. Fiber Reinforced Polymer (FRP) composites provide a highly adaptable solution for reinforcing and revitalizing existing structures in challenging marine conditions. This study delves into investigating the flexural characteristics of FRP pine wood composites, comparing the findings with Finite Element Analysis (FEA) results. Furthermore, the activated carbon derived from pine wood exhibits potential for resisting barnacle attachment when immersed in saltwater. For the flexural analysis, samples were produced using a silicone rubber mold, incorporating varying weight percentages (wt.%) of activated FRP pine wood, ranging from 2 wt.% to 10 wt.%. The outcomes of the study reveal that the introduction of activated carbon from pine wood leads to an enhancement in ultimate strength, reaching a maximum of 2700 MPa. Nonetheless, the results also indicate a reduction in material strength as the proportion of activated carbon pine wood is increased.

This research investigates the effectiveness of bio-sourced flax fiber-reinforced polymer in comparison with a traditional system based on carbon fiber-reinforced epoxy polymer in order to confine recycled aggregate concretes. The experimental investigation was conducted on two series of concrete including three mixtures with 30%, 50%, and 100% of recycled aggregates and a reference concrete made with natural aggregates. The concrete mixtures were intended for a frost environment where an air-entraining agent was added to the mixture of the second series to achieve 4% air content. The first part of the present work is experimental and aimed to characterize the compressive performance of confined materials. The results indicated that bio-sourced composites are efficient in strengthening recycled aggregates concrete, especially the air-entrained one. It was also found that the compressive strength and the strain enhancement obtained from FRP confinement are little affected by the replacement ratio. The second part was dedicated to the analytical modeling of mechanical properties and stress–strain curves under compression. With the most adequate ultimate strength and strain prediction relationships, the full behavior of FRP-confined concrete can be predicted using the model developed by Ghorbel et al. to account for the presence of recycled aggregates in concrete mixtures.

The development of earth-based bio-sourced materials requires a thorough analysis of the study soil. For the present study, we took five (05) soil samples from a tunnel-digged quarry in the layer between 0.5 m and 5 m : white clay (MSB-BL), red clay (MSB-RG), weak clay or sandy clay (MSB-FB), strong clay (MSB-FR) and mixture (MSB-ME). To verify the quality of these five (05) soils samples, their intrinsic properties were determined at the National Building and Public Works Laboratory (LNBTP). These included grain size, clay content, specific weight, loss on ignition and moisture content. These analyses revealed that MSG-RG and MSG-BL clays have fine fractions of 64.28% and 47.85% respectively; clay fractions of 27.51% and 20.61% respectively; and methylene blue values in the range (6;8). Their plasticity indices are in the range (20;40). These two (02) clays thus meet the requirements in terms of granularity, and their relatively high clay fraction will favor their adhesion with admixtures such as plant fibers. What's more, the particle size distribution of these clays is within the ideal CRAterre range for soils used in the manufacture of BTC or adobes, so they are all eligible.

Materials that are both biodegradable and bio-sourced are becoming serious candidates for substituting traditional petro-sourced plastics that accumulate in natural systems. New biocomposites have been produced by melt extrusion, using bacterial polyester (poly(3-hydroxybutyrate-co-3-hydroxyvalerate)) as a matrix and cellulose particles as fillers. In this study, gas-phase esterified cellulose particles, with palmitoyl chloride, were used to improve filler-matrix compatibility and reduce moisture sensitivity. Structural analysis demonstrated that intrinsic properties of the polymer matrix (crystallinity, and molecular weight) were not more significantly affected by the incorporation of cellulose, either virgin or grafted. Only a little decrease in matrix thermal stability was noticed, this being limited by cellulose grafting. Gas-phase esterification of cellulose improved the filler’s dispersion state and filler/matrix interfacial adhesion, as shown by SEM cross-section observations, and limiting the degradation of tensile properties (stress and strain at break). Water vapor permeability, moisture, and liquid water uptake of biocomposites were increased compared to the neat matrix. The increase in thermodynamic parameters was limited in the case of grafted cellulose, principally ascribed to their increased hydrophobicity. However, no significant effect of grafting was noticed regarding diffusion parameters.

The compatibility between poly(lactic acid) (PLA) and natural fibers to develop bio-sourced, recyclable, and biodegradable composites remains a commonplace issue. This work highlights that, at least in the case of hemp, pulping and bleaching towards delignified short fibers attained remarkable improvements over untreated hemp strands. This approach differs from usual proposals of chemically modifying hydroxyl groups. Soda-bleached hemp fibers (SBHFs) granted a relatively large bonding surface area and a satisfactory quality of the interphase, even in the absence of any dispersant or compatibilizer. To attain satisfactory dispersion, the matrix and the fibers were subjected to kinetic mixing and to a moderately intensified extrusion process. Then, dog-bone specimens were prepared by injection molding. Up to a fiber content of 30 wt.%, the tensile strength increased linearly with the volume fraction of the dispersed phase. It reached a maximum value of 77.8 MPa, signifying a relative enhancement of about 52%. In comparison, the tensile strength for PLA/hemp strands was 55.7 MPa. Thence, based on the modified rule of mixtures and the Kelly & Tyson modified equation, we analyzed this performance at the level of the constituent materials. The interfacial shear strength (over 28 MPa) and other micromechanical parameters were computed. Overall, this biocomposite was found to outperform a polypropylene/sized glass fiber composite (without coupling agent) in terms of tensile strength, while fulfilling the principles of green chemistry.

Bio-sourced materials combined with a polymer matrix offer an interesting alternative to traditional building materials. To contribute to their wider acceptance and application, an investigation into the use of wood-polymer composite boards is presented. In this study, biocomposite boards (BcB) for the building industry are reported. BcB are fabricated using a dry incorporation method of corn starch (CS) and hemp shiv (HS) treatment with water at 100 °C. The amount of CS and the size of the HS fraction are evaluated by means of compressive bending and tensile strength, as well as microstructure. The results show that the rational amount of CS independently of HS fraction is 10 wt.%. The obtained BcB have compressive stress at 10% of deformation in the range of 2.4–3.0 MPa, bending of 4.4–6.3 MPa, and tensile strength of 0.23–0.45 MPa. Additionally, the microstructural analysis shows that 10 wt.% of CS forms a sufficient amount of contact zones that strengthen the final product.

The growing interest in research and development of eco-friendlier materials makes attractive the use of bio-based and biodegradable polymers such as polylactic acid (PLA). However, the higher cost of PLA compared to conventional polymers limits its applications. Moreover, raw materials for rotational molding must be in a powder form, which further increases their cost. So, the main objective of this study was to use agave fibers to produce lower-cost PLA based rotomolded biocomposites (BC) without compromising its bio-sourced origin and to compare with a standard rotomolding resin: linear medium density polyethylene (LMDPE). To improve the fiber-matrix interface, a chemical surface treatment of the fibers with glycidyl methacrylate grafted polylactic acid (GMA-g-PLA) in solution was evaluated. The results showed that a better biocomposites’ morphology was obtained, especially with the fibers treated twice. The surface treatment was also shown to substantially improve the flexural and tensile properties of treated fiber biocomposites at higher fiber content (25% wt.) compared to those with untreated fiber. The surface treatment also led to a substantial reduction of the biocomposites porosity and water absorption. Overall, the samples were shown to have better mechanical properties than neat LMDPE while being eco-friendlier due to their bio-nature.

ABSTRACTBlack liquor is a by-product of the paper mill Kraft process that deserves more valorization than its present use as low-grade fuel. In this work, SiC/C composite foams were prepared for the first time from concentrated emulsions by carbothermal reduction of bio-sourced precursors combining sodium silicate by lignin at 1400°C. The composition of the materials was determined by XRD, FTIR and Raman analyses. Their porous structure was characterized by SEM, mercury intrusion porosimetry, and nitrogen sorption, while their thermal properties were measured by TGA and dynamic DSC. Concerning their heat transport properties, we found out that when the starting lignin content was increased, the final C/Si ratio, the specific surface area and the heat diffusivity increased as well. Its high values were attributed to a cooperative effect between radiative heat transfer and the presence of partially graphitized carbon.

Two major obstacles to utilizing polyhydroxybutyrate (PHB)—a biodegradable and biocompatible polymer—in commercial applications are its low tensile yield strength (<10 MPa) and elongation at break (~5%). In this work, we investigated the modification of the mechanical properties of PHB through the use of a variety of bio-derived additives. Poly(lactic acid) (PLA) and sugarcane-sourced cellulose nanocrystals (CNCs) were proposed as mechanical reinforcing elements, and epoxidized canola oil (eCO) was utilized as a green plasticizer. Zinc acetate was added to PHB and PLA blends in order to improve blending. Composites were mixed in a micro-extruder, and the resulting filaments were molded into 2-mm sheets utilizing a hot-press prior to characterization. The inclusion of the various additives was found to influence the crystallization process of PHB without affecting thermal stability. In general, the addition of PLA and, to a lesser degree, CNCs, resulted in an increase in the Young’s modulus of the material, while the addition of eCO improved the strain at break. Overall, samples containing eCO and PLA (at concentrations of 10 wt %, and 25 wt %, respectively) demonstrated the best mechanical properties in terms of Young’s modulus, tensile strength and strain at break.

ABSTRACT A simple, versatile, sustainable, not expensive method for the functionalization of sp2 carbon allotropes, both nano-sized and nano-structured, without altering their bulk crystalline organization, is presented. Carbon materials available at the commercial scale were used: furnace carbon black (CB), nano-sized graphite with high surface area, and multiwalled carbon nanotubes. A bio-sourced molecule, 2-(2,5-dimethyl-1H-pyrrol-1-yl)-1,3-propanediol (serinol pyrrole), was used for the functionalization. Serinol pyrrole (SP) was obtained from serinol through a reaction with atomic efficiency of about 82%, performed in the absence of solvents or catalysts. Synthesis of serinol pyrrole was performed as well on carbon allotropes as the solid support. Adducts of serinol pyrrole with a carbon allotrope were prepared with the help of either thermal or mechanical energy. Functionalization yield was in all cases larger than 90%. With such adducts, stable dispersions in water and in NR latex were prepared. A few layers of graphene were isolated from the water dispersions, and NR-based composites precipitated from the latex revealed very even distribution of fine graphitic particles. Composites were prepared, based on NR, IR, and BR as the rubbers and CB and silica as the fillers, with different amounts of CB–SP adduct, and were cross-linked with a sulfur-based system without observing appreciable effect of functionalization on vulcanization kinetics. The CB–SP adduct led to appreciable reduction of the Payne effect.

A major societal issue of disposal and environmental pollution is raised by the enormous and fast-growing production of single-use polyethylene terephthalate (PET) bottles, especially in developing countries. To contribute to the problem solution, an original route to recycle PET in the form of value-added environmentally friendly thermoplastic composites with banana fibres (Musa acuminata) has been developed at the laboratory scale. Banana fibres are a so far undervalued by-product of banana crops with great potential as polymer reinforcement. The melt-processing constraints of commercial PET, including used bottles, being incompatible with the thermal stability limits use of natural fibres; PET has been modified with bio-sourced reactants to produce co-polymers with moderate processing temperatures below 200 °C. First, commercial PET were partially glycolyzed with 1.3-propanediol to produce co-oligomers of about 20 repeating units, which were next chain extended with succinic anhydride and post-treated in a very unusual “soft solid state” process at temperatures in the vicinity of the melting point to generate co-polymers with excellent ductility. The molar mass build-up reaction is dominated by esterification of the chain ends and benefits from the addition of succinic anhydride to rebalance the acid-to-hydroxyl end-group ratio. Infra-red spectroscopy and intrinsic viscosity were extensively used to quantify the concentration of chain ends and the average molar mass of the co-polymers at all stages of the process. The best co-polymers are crystallisable, though at slow kinetics, with a Tg of 48 °C and a melting point strongly dependent upon thermal history. The composites show high stiffness (4.8 GPa at 20% fibres), consistent with the excellent dispersion of the fibres and a very high interfacial cohesion. The strong adhesion can be tentatively explained by covalent bonding involving unreacted succinic anhydride in excess during solid stating. A first approach to quantify the sustainable benefits of this PET recycling route, based on a rational eco-selection method, gives promising results since the composites come close to low-end wood materials in terms of the stiffness/embodied energy balance. Moreover, this approach can easily be extended to many other natural fibres. The present study is limited to a proof of concept at the laboratory scale but is encouraging enough to warrant a follow-up study toward scale-up and application development.

The quantity of municipal solid waste (MSW) generation is escalating at an alarming rate with every passing year alongside the modernization of our economy. Unfortunately, the majority of this waste remains uncollected or ends up in open dumping and followed by uncontrolled burning. Citing the deep-rooted consequences, open dumping should be absolutely abandoned and scientific interventions should be aggressively exercised to reclaim the municipal brownfields. The present research work undertook the judicial task of assessing the comparative feasibility of biomining and scientific capping as a technology selection for reclamation of about a decade old 120 million tons of waste chunk laying at Jawahar Nagar dump yard. Primary dump samples were collected from various locations, considering depth as a variable. While leachate and groundwater samples were collected from Malkaram lake and preinstalled borewells receptively. Additionally, the ambient air quality and noise level also been ascertained within the buffer zone. The blended representative solid sample was segregated using a 70 mm mesh size trommel into organic and inorganic fractions. The organic fraction was composted using a lab-scale aerobic static pile composting (ASPC) while the trommel reject was processed as refuse derived fuel (RDF). Evidently, the compost lagged quality and depicted nutrient deficiency. While the burning of RDF produced siloxane gas, significantly due to elevated silicon level in the primary waste. Furthermore, due to the prolonged leaching tenure and seasonal dilution, the concentration of legacy leachate was relatively weaker. Borewell samples collected from a depth of 20 feet also portrayed minor contamination up to 500 meters horizontal radius. The issue of leachability can solely be resolved with the capping of the existing dump and the end product quality derived from the biomining process is highly questionable. Thus, handling such large quantity capping is a befitting option over biomining for Jawahar Nagar dumpsite. INTRODUCTION Presently, in India due to rapid urbanization and industrialization, the generation of MSW has been increasing tremendously and also expected to continue a similar trend in the future (Scott, 1995; Bhat et al., 2017; Sethurajan et al., 2018; Sharma et al., 2018). Annually, the comprehensive urban MSW generation in India is more than 62 million tons. Metro cities are the mammoth contributor of the entire chunk and waste production had already reached an alarming figure of 50,000 tonnes/day. While the waste generation from the tier 2 cities is also rigorously escalating and presently contribute up to 20,000 tones/day (Sharma et al., 2018). A study conducted by the central pollution control board (CPCB) revealed MSW generation in India is increasing at a distressing rate of 5 % per annum with a sharp escalation in the quantities of domestic hazardous waste (Sharma et al., 2018). With major financial constraints, inefficacy of collection, treatment, and disposal incurs further reasons to worry. So far India has miserably failed to set up wholesome source segregation and collection method. Presently, the country spends more than 60% of its annual waste management budget only in collection. Besides, only 20% or less of the collected materials are scientifically handled and treated. Citing the statistics, it is evident that the majority of the MSW is simply gets dumped on the low laying grounds located somewhere on the outskirts of the cities. The precipitation, infiltration, surface water runoff, bird menace, rodent interference etc. triggers the vulnerability of waste and leads to mal odor, ground and surface water contamination, human and environmental health deterioration (Jayawardhana et al., 2016). Further, the perseverance of the inorganic and inert fractions leads to soil contamination, poses a fire threat, and also may incur carcinogenicity and acute toxicity among the animals (Mir et al., 2021). There are numerous techniques for the reclamation and remediation of the dumpsites, includes processes such as capping and closure, in-situ vitrification, sub-surface cut-off walls, and waste biomining (Chakrabarti and Dubey, 2015; Thakare and Nandi, 2016). Waste biomining is a stable way to get rid of the entire range of problems associated with open dumping and reclaim valuable land (Kaksonen et al., 2017). There are several instances including reclamation of Mumbai Gorai dump yard by IL & FS Environment, 70 – 80 years old 12,00,000 tons of dump clearance by Nagar Nigam Indore within a minute span of 3 years and many more. But the process of biomining is highly sensitive and case-specific. The success of the process solely depends on factors such as characteristics of the waste, efficacy of the effective microorganism culture, acceptability of the processed end product at the local market etc. (Jerez, 2017; Banerjee et al., 2017; Venkiteela, 2020). Contrarily, though the scientific capping is not an end-to-end solution but still advisable in the cases where the quantity of waste is gigantic, land scarcity is prevalent, no nearby industries to consume the end products etc. Mehta et al. (2018) have also supported the above claim based on the assessment of locations specific MSW dump reclamation case studies. While in another Nagpur-based case study conducted by Ashootosh et al. (2020) reported the superiority of the biominingprocess over simple land capping due to the favorability of the local conditions. Capping eliminates the environmental interference and thereby reduces biosphere contamination and leachate generation. Further, it captivates rodent and vector breeding and thereby curtails the spreading of communicable diseases and improves aesthetics. But right consolidation through compaction and execution is utmost necessary in the above case. As non-compaction and faulty sloping will easily lead to heavy settlement and slope failure (Berkun et al., 2005; Al-Ghouti et al., 2021). The present study has been pursued with the primary objective to run a techno-commercial assessment between scientific capping and biomining. While the secondary objective was to ascertain the level of contamination and propose mitigative measures. MATERIALS AND METHODStudy Area Spanning over 350 acres of a precious piece of land at the outskirts of Hyderabad city, Jawahar Nagar dumping yard was brutally utilized by the Greater Hyderabad Municipal Corporation (GHMC) for open dumping for a prolonged tenure of 10 years. It housed nearly 12 lakh metric tons of heterogeneous solid and domestic hazardous waste and continues polluting until 2015, until the Ramky group was offered to cap the legacy dumping and scientifically handle the site. The present study has been facilitated at Hyderabad Municipal Solid Waste Limited, formerly known as Jawahar Nagar dump yard to analyze and assess the feasibility of bio-mining as handling and management alternate to the existing practice of scientific capping. The epicenter of processing and disposal facility is lying approximately on the cross-section of 17°31'24.45"N and 78°35'23.37"E. As per the contract, the comprehensive legacy dumping to be capped in three phases over about 150 acres of area and Ramky has significantly entered the phase two of the operation only within a span of five years by successfully capping more than half of the legacy footprint. Sampling Methodology The waste pile was divided into three layers namely, base, middle, and top. A uniform amount of sample was collected from the successive layers of all five different corners which cover north, south, east, west, and central of the garbage pile. Sampling inspections were performed using a manual auger besides large samples were collected using a JCB excavator. The top six-inch layer of the pile was removed to avoid any contamination while collecting the samples and 5-10 kg of sample was collected from each of the locations. Further, intermediate and bottom layer samples were collected by digging a 500 mm diameter hole through the heap. A composite was prepared by a homogenized blending of all the fifteen grub samples. The blend was distributed into four equal quadrants and the top and bottom quadrants were eliminated diagonally while the left-over quadrants were mixed thoroughly. This process was repeated until a sample of the required bulk of 20 kg is obtained. Surface and subsurface water samples from borewell were collected in and around the facility. Piezometric monitoring borewells located near the landfills were utilized for the subsurface sample collection. While a rainwater pond turned leachate lake named Malkaram was determined as the primary source for leachate collection. Buffer samples were collected from Ambedkar Nagar, the nearby colony exiting at a distance of only 300 meters. Lab-scale Experimentation The representative sample was characterized for composition and further screened through a 70 mm mesh size trommel. The trommel permeate was considered as the organic fraction while the reject was mostly inorganics and inert. The organics were subjected to ASPC. The quantity of the air required is arrived using the method delineated below (Figure 1). MSW Pile size: 2m x 0.5m x 0.5m Volume of pile: 0.5 m3 Average Density of MSW: 620 Kg/m3 Weight of pile: 310 Kg Nitrogen required for matured compost: 9300 mg/kg dry : 9300 X 310 mg : 2.88 x 106 mg : 2.88 Kg Total air required: 2.88 x 100/76 [as Nitrogen in air is 76% by weight] : 3.79 Kg of dry air : 3.79/1.225 m3 [@ 15 deg C density of air 1.225 kg/m3] : 3.1 m3 This air is to be supplied for 100 min / day for 0.5 m pile Air flow rate required: 3.1 x 60/100 = 1.86 m3/h (for practical purpose a flowrate of 2 m3/h was maintained). The maturation period was considered as 28 days and post-maturation, the stabilized material was further cured for 24 hours and screened using 12 mm and 4 mm trommel respectively to obtain the desired product quality and particle size. Whereas, the trommel reject was evenly spreader on the copper trays and dried in an oven at 1050C for 2 hours. The dried material was micronized to the size of 50 mm or below using a scissor and inert such as glass, sand, stone etc. were segregated manually (Mohan and Joseph, 2020). Concurrently, a bench-scale capped landfill prototype was built using the below-mentioned procedure to evaluate the factors such as settlement and slope stability. A 30 mm thick low permeable soil was laid on the top of the waste, followed by a 60 mm layer of compacted clay liner (CCL). Each join between successive liner material was closely monitored. A 1.5 mm thick HDPE liner was placed on the top of the CCL. A 285 GSM geotextile membrane was placed as the successive above layer followed by a 15 mm thick drainage media layer. A further layer of geotextile membrane was placed on top of the drainage media for better stabilization, grip, and strength. The top vegetative soil layer of 45 mm thickness was laid off on top of the geotextile media and St. Augustine grass was rooted (Cortellazzo et al., 2020; Ashford et al., 2000). 2.4 Sample Analysis pH, Electrical Conductivity (EC) and Turbidity of the samples were analyzed using pH, EC-TDS, and Nephelometer of Mettler Toledo. The pH meter was calibrated with the buffer solution of 4.0, 7.0 & 9.12 at a controlled temperature. EC-TDS meter was calibrated with 0.1 M KCL having 12.8 mS/cm of conductivity. Nephelometer was calibrated with Formazine solution of 10 & 100 NTU. Total Dissolved Solids (TDS), (mg/L) was performed using the gravimetric method at 1800C in the oven. Titrimetric parameters such as Total Alkalinity as CaCO3 (mg/L), Total Hardness as CaCO3 (mg/L), Chloride as Cl- (mg/L), Calcium as Ca2+ (mg/L), Residual Free Chlorine (RFC), (mg/L) were analyzed using APHA (American Public Health Associations) method, 23rd Edition, 2017. Total Kjeldahl Nitrogen (mg/L) and Ammonical Nitrogen (mg/L) were performed through distillation followed by titration with H2SO4 as a titrant. Sulphide as S2- was done with the Iodometric method after distillation. Each titrimetric parameter was analyzed in triplicate after standardizing the titrant with required reagents and crossed checked by keeping a check standard. Sodium as Na (mg/L) and Potassium as K (mg/L) were performed using Flame Photometer. The photometer was calibrated with different standards from 10 to 100 (mg/L) standard solutions. The leachate sample was diluted enough to get the value within the standard range and cross-checked with check standards at the same time. Chemical Oxygen Demand (COD), (mg/L) was performed using the open reflux method for 2 hours at 1500C in COD Digestor. Biochemical Oxygen Demand (BOD), (mg/L) was performed using the alkali iodide azide method for 3 days. The samples were kept in a BOD incubator at 270C for 3 days. It was kept in duplicate to have a check on quality control. Sulphate was analyzed by the gravimetric method instead of turbidimetric or through UV-Visible spectrophotometer as its concentration was found more than 40 mg/L. Nitrate as NO3- was analyzed after filtration at 220-275 nm, while Hexavalent Chromium as Cr6+ was analyzed at 540 nm in the UV-Vis. Parameters like Cyanide as CN-, Fluoride as F-, and Phenolic Compounds were gone through a distillation process followed by UV-Vis. The distillation process ensures the removal of interferences presents either positive or negative. For the parameters like Total Iron or Ferric Iron, the samples were digested properly with the required reagents on the hot plate before analyzing in UV-Vis. For the metal analysis the water samples were digested at a temperature of 1000C using aqua regia as a media. The samples were digested to one-fourth of the volume on a hot plate. The recommended wavelengths as per APHA 3120 B were selected for each of the metals. The standard graph was plotted for each of the metals before analysis and crossed checked with the check standard at the same time. Parameters such as bulk density and particle size were performed through the certified beaker and sieve. The percentage of moisture content was estimated using the oven by keeping the compost sample for 2 hours at 1050C. C/N ratio was estimated through CHNS analyzer keeping sulfanilamide as a check standard. The analysis was performed by extracting the desired component in the desired solution prescribed in the method followed by converting the same from mg/L to mg/Kg. RESULTS AND DISCUSSION An exhaustive bench-study has been pursued and real-time samples were collected and analyzed for all possible parameters to determine the pros and cons attributed to both processes. The investigation begins by collecting the samples and concluded by impact assessment studies inclusive of the buffer zone. Both solid, liquid, and gaseous samples were precisely investigated to opt for the best solution. A detailed finding of the investigation is summarized below. Primarily, the representative solid sample was characterized through a manual separation process and the results are portrayed in Figure 1. Compost Characterization ASPC of the organic fraction has resulted in a recovery of 46.7% of the initial load. While 53.3% of the influent mass were inert and barely degradable fraction contributes to reject, the rest 4.1% is miscellaneous process loss. The processed compost was extensively analyzed including for metal contamination and the same is tabulated in Table 1. The value of C/N ratio, OC, TN, K2O, P2O5, and NPK evidently portrays the shortcoming in terms of nutrient availability. Though it is highly enriched in organic carbon and thus the same can be effectively utilized as a soil preconditioner. Ayilara et al. (2020) also reported a similar finding, where the city compost sourced from MSW lagged major plant nutrients. RDF Characterization Processed trommel rejects constitute cloth, rexine, leather, jute, paper, plastics, coir and other inert contributed to RDF. The fraction of inert was as high as 37.2% of the overall RDF mass and it mostly constituted glass and sand. The combined weight of sand and glass fragments contributed 73.5% of the total inert, while the rest was stone and small brickbats. The higher level of silicon associated with the presence of glass and sand yielded siloxane and triggered the possibility of kiln corrosion. A detailed RDF analysis report is enclosed in Table 2. The values explicitly portray the quality of RDF is moderately lower and higher salts concentration is extremely prevalent. With relatively lower NCV and such high salt concentration, the above specimen will certainly pose a corrosion threat to the kiln and shall be either neglected as kiln feed or can be utilized after dilution with Grade III RDF quality. Further, such high ash generation will also induct high transportation and landfill charges. Leachate Characterization The Malkaram leachate lake is the end result of prolonged, slow, and steady mixing of the legacy leachate through the existing fissure cracks in the sheath rock bottom profile. Apparently, the concentration of leachate is significantly lower due to the dilution. Samples were analyzed in triplicates and the mean value is tabulated here in Table 3. The metal concertation and rest of the parameter values are well within the secondary treatment influent range, except for TDS. Thus, a modular aerobic biological treatment unit such as moving bed biofilm bioreactor (MBBR) or membrane bioreactor (MBR) would be a well-suited pick. However, a reverse osmosis (RO) system needs to be installed to get rid of the high TDS content. The permeate of RO can be reused back into the system. Whereas, the reject can be converted into dried powder through forced evaporation mechanisms. The higher concentration of salts in RDF collaterally justifies the elevated TDS level in leachate. In a leachate impact assessment study performed by El-Salam and Abu-Zuid (2015) the reported BOD/COD ratio of 0.69 is greater than double the value of 0.301 reported in Table 3. Though the difference in both the values are quite high, it is relatable and justifiable by the huge age difference of the source waste. The primarily characterized data is of a fresh leachate generated from regular MSW, while the later one is from a decade old waste that barely has any unstabilized organic content. Groundwater Contamination The obvious reason for downward leachate infiltration and osmotic movement facilitates groundwater contamination. Both surface and subsurface water samples were collected within the dump yard and the buffer zone and analyzed using the standard methods. The results are portrayed in Table 4. The slightly alkaline pH of the borewell sample is an indication of the ongoing anaerobic process. The dissolved oxygen value of 3.5 mg/L further validates the correlation. Higher TDS and hardness values are self-indicative of elevated salt concentration in source waste. Eventually, the same interfered with the RDF quality. Positively in the case of all the parameters, a successive decrement in pollution concentration has been spotted from dump ground towards the buffer zone. In a similar study conducted by Singh et al. (2016) at Varanasi, Uttar Pradesh the reported concentration of the parameters is significantly higher than reported in Table 4. The basic reason behind variation is the dissimilarities of the local soil profile. The sandy and clay loam soil profile of Varanasi allows a greater rate of percolation and infiltration. While the bottom sheath rock profile at Jawahar Nagar permits the only a minute to little percolation rate. The difference in percolation rate is directly correlated to the concentration levels in this case. Contrarily, Kurakalva et al. (2016) have reported much-elevated pollutant concertation both in ground and surface water for a study conducted at the same site in 2016. The higher concentration is relatable to the fact of the non-closure of the open dump back then. Capping activity had at Jawahar Nagar gained its pace 2018 onwards and capping for the primary section of 70 acres got concluded only during mid of 2019. Due to the decrement in runoff and percolation, the quality of both surface and subsurface water has improved drastically. Impact Assessment The odor and groundwater contamination are two of the primary issues that triggered a massive public agitation initially. The root causes of both the issues are identified as rainwater percolation and anaerobic digestion respectively. Eventually, the completion of the capping process would resolve both the problems effectively. Other non-tangential impacts include nausea; headache; irritation of the eye, nasal cavity, and throat; diarrhoeal diseases; vector-borne disease, cattle toxicity etc. Scientific capping can easily cater as the wholesome solution for all (Cortellazzo et al., 2020). Yu et al. (2018) had performed an extensive study to comprehend the relativity of respiratory sickness and MSW borne air pollution. The study made a couple of dreadful revelations such as gases released due to the anaerobic digestion of MSW such as methane, hydrogen sulphide, and ammonia incur detrimental impact on Lysozyme and secretory immunoglobulin A (SIgA). While SO2 was reported as the lung capacity and functionality reducer. Further, a gender-specific study executed by the same research group revealed, air pollution impacts more severely on male children than the female and retards immune functions. Presently, the area of 351 acres has been developed as Asia’s one of the largest state of the art municipal solid waste processing and disposal facility by Ramky Enviro Engineers Limited. This ensured zero dumping and no further environmental interventions. As legal compliance, the facility monitors the quality of groundwater and ambient air quality in and around the facility on monthly basis to assure the biosafety. The variation in concentration of various monitoring parameters between 2012 to 2020 is summarized in Figure 2. The concentration of each of the parameters are showcased in ppm and a standard equipment error was settled at 3% for respirable dust sampler and multi-gas analyzer (Taheri et al., 2014). Despite all parameter values have gradually increased except for methane, the facility still managed to maintain them well under the regulatory limits. The decrement in methane concentration is directly correlated to the practice of aerobic composting and aeration-based secondary treatment that prevented the formation of the anaerobic atmosphere and henceforth methane generation. While for the rest of the parameters the increment in values is quite substantial and predictable due to the sudden escalation in MSW generation in the past decade in correlation with Gross domestic product (GDP) enhancement. The observed and interpreted impacts due to the elevated pollutant level are in-line with the georeferenced findings reported by Deshmukh and Aher (2016) based on a study conducted at Sangamner, Maharashtra. CONCLUSION The study critically analyzed and investigated every techno-environmental and socio-economic aspect correlated to open dumping. The bench-scale experimentation revealed the efficiency of the single liner scientific capping is fair enough to eliminate any further rainwater infiltration, however, it has no control over the generation of leachate due to the inherent moisture. Internal moisture related issue was anyhow compensated with pertinent compaction prior to dispose of the waste. Contrarily, both the products derived through the biomining process namely, compost and RDF lagged quality due to scantier nutrient content and higher salt and silicon content respectively. Besides, impact assessment studies concede the pollutant concentration in groundwater in and around the plant has drastically diminished post-July 2019 due to the partial completion of waste capping. It also abetted lowering the dust and odor issues relatively in the surrounding. ACKNOWLEDGMENT The authors would like to sincerely acknowledge GHMC, Hyderabad Integrated Municipal Solid Waste Limited, and Ramky Enviro Engineers Limited for enabling us to pursue the sample collection and other necessary onsite activities. Further, the authors would like to register profound acknowledgment to EPTRI for supporting us with the essential experimental facilities. REFERENCES Sharma, A., Gupta, A.K., Ganguly, R. (2018), Impact of open dumping of municipal solid waste on soil properties in mountainous region. 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New thermoset composite material made from cardanol-based resin blended with microfibrillar cellulose was compared to petroleum-based vinyl ester and glass-fiber-reinforced unsaturated polyester in terms of mechanical, thermal, rheological and surface properties of produced polymers and composites. The bio-sourced material was less resistant than the commercial vinyl ester but comparable to the unsaturated polyester resin. Microfibrillar cellulose increased the tensile strength and modulus but increased the resin viscosity and decreased the mixture homogeneity. The bio-sourced and commercial resins displayed similar hydrophobic behavior, and cellulose slightly decreased composite hydrophobicity. The glass transition temperature of the bio-sourced material was comparable to that of the unsaturated polyester. Thermal decompositions of composites and thermoset polymers were also similar. Cellulose and cardanol thus may be adequate as sustainable components in the composite materials industry.

Nowadays, there is a rising demand for bio-composite materials driven by the increasing need for sustainable alternatives and a desire to lessen dependence on conventional materials. These bio-composites resent eco-friendly solutions to address these challenges. In line with this, the present study focuses on the bio composite material which developed from polylactic acid (PLA) and wood dust (NF). Wood dust sourced from teak wood plants was employed as fillers. PLA served as the matrix material, supplemented with the plasticizer polyethylene glycol (PEG) to enhance PLA processing. The PLA/NF filament was produced through the extrusion process, and specimens were prepared using 3D printing techniques in accordance with ASTM standards. Various properties including mechanical, physical, thermal stability, and tribological properties were examined. Morphological structures were observed using scanning electron microscopy (SEM). The test results demonstrated improvements in enhanced mechanical robustness and tribological performance of the PLA composite. The tensile strength of the PLA/wood composite was enhanced by 11%. The hardness value of the PLA/wood composite increased by 27% with the addition of wood as filler material. However, the introduction of wood as filler material led to degradation in physical properties. The water absorption test revealed a thickness change of approximately 14% for the PLA wood composite, whereas for pure PLA, it was 9%. Thermal stability tests showed that the temperature resistance of PLA improved to 250 °C with the introduction of wood fillers. Biodegradability tests indicated that PLA wood composite has the potential to address environmental concerns associated with conventional materials.

The aging of buildings and structures, accompanied by an increase in the prices of conventional building materials, has pushed the scientific community to explore new techniques and materials to rehabilitate existing buildings. Rehabilitation aims to extend the service life of a structure while maintaining its strength and stability. Among these techniques, composite materials based on synthetic fibers, such as carbon fibers, have been developed. However, materials with low carbon footprints that are bio-sourced and eco-friendly are of interest to the scientific community. The use of Alfa plant natural stems in a braided form is the focus of this study. This study is the first to use geometric shapes to improve the performance of a natural fiber-reinforced composite. Epoxy was used as the matrix, which is the material used most often in composite designed for reinforced concrete structures. This study aims to determine the equivalent mechanical properties of the Alfa braided stem using the reverse method. Test specimens of the epoxy/Alfa composites were manufactured and tested on a tensile machine. The epoxy was tested, and its properties were determined. Subsequently, a finite element numerical model of the specimen was constructed, and the properties of the braided Alfa stem were varied until identical results were obtained. The mechanical properties of the Alfa braided stem were thus identified. The results showed that the braided Alfa stem had a stiffness modulus of 23.243 GPa.

Abstract This study concerns a new ecological material, bio-sourced and with reduced environmental impact. The material in question is a composite made from date palm fibers and lime. For the development of this material, we were inspired by the techniques used for the manufacture of hemp concrete. The latter is widely used especially in France for the thermal insulation of buildings. The idea is to design an insulation material from the natural resources of the southern Algerian region. The material made is a lightweight concrete that could provide both thermal and acoustic insulation. By its porous morphology, it also has the ability to absorb water vapor when it is in an environment with high relative humidity and to release the vapor if the environment is dry. It could therefore play the role of a water regulator. Experimental investigations revealed interesting mechanical and hydrous properties. Measurements of the moisture buffer value (MBV) reveal that according to the current standard, the material is classified between good and excellent. As regards the mechanical strength, the material produced has an acceptable compressive strength.

AbstractThe use of photopolymerization is expanding across a multitude of biomedical applications, from drug delivery to bioprinting. Many of these current and emerging photopolymerization systems employ visible light, as motivated by safety and energy efficiency considerations. However, the “library” of visible light initiators is limited compared with the wealth of options available for UV polymerization. Furthermore, the synthesis of traditional photoinitiators relies on diminishing raw materials, and several traditional photoinitiators are considered emerging environmental contaminants. As such, there has been recent focus on identifying and characterizing biologically sourced, visible light‐based photoinitiator systems that can be effectively used in photopolymerization applications. In this regard, several bio‐sourced molecules have been shown to act as photoinitiators, primarily through Type II photoinitiation mechanisms. However, whether bio‐sourced molecules can also act as effective synergists in these reactions remains unknown. In this study, we evaluated the effectiveness of bio‐sourced synergist candidates, with a focus on amino acids, due to their amine functional groups, in combination with two bio‐sourced photoinitiator molecules: riboflavin and curcumin. We tested the effectiveness of these photoinitiator systems under both violet (405 nm) and blue (460–475 nm) light using photo‐rheology. We found that several synergist candidates, namely lysine, arginine, and histidine, increased the polymerization effectiveness of riboflavin when used with both violet and blue light. With curcumin, we found that almost all tested synergist candidates slightly decreased the polymerization effectiveness compared with curcumin alone under both light sources. These results show that bio‐sourced molecules have the potential to be used as synergists with bio‐sourced photoinitiators in visible light photopolymerization. However, more work must be done to fully characterize these reactions and to investigate more synergist candidates. Ultimately, this information is expected to expand the range of available visible light‐based photoinitiator systems and increase their sustainability.

AbstractThe additive manufacturing (AM) industry increasingly looks to differentiate itself by utilizing materials and processes that are green, clean, and sustainable. Biopolymers, bio‐sourced raw materials and light weighting of parts 3D printed with photopolymer resins each represent critical directions for the future of AM. Here, we report a series of bio‐based composite resins with soybean oil derivatives, up to 20% by weight of surface‐methacrylated micro‐crystalline cellulose (MCC) and 60% total bio‐based content for vat photopolymerization based additive manufacturing. The ultimate tensile strengths of the materials were found to increase up to 3X, the Young's moduli increased up to 10X, and the glass transition temperature increased by 11.3°C when compared to the neat resin without surface‐methacrylated MCC as a filler. Working curves and shrinkage factors were used to demonstrate how the surface‐methacrylated MCC causes changes in the dimensions of printed parts, to facilitate development of optimized print parameters based on the UV intensity of the 3D printer being used. These results will allow further development of commercial 3D printable resins with a high concentration of bio‐based fillers that print well and perform on par with conventional resins.

Toothbrush handles made from synthetic polymers like polypropylene and polyethylene accumulate in the environment at an annual rate of 1 billion devices per year and without significant degradation, resulting in severe burdens particularly in marine environments. Herein, we report a new process to generate these plastic handles using natural, biopolymer-based components using a direct thermoplastic molding approach, that also offers on-demand degradation of the materials. The materials are prepared directly from whole silk cocoons that are thermoplastically transformed into biodegradable plastic parts for consumer needs, here in the form of toothbrush handles; either with silk alone or in combination with other natural sourced materials such as cellulose, chitosan and hydroxyapatite. We demonstrate the on-demand degradation of these bioplastics in different ways, using natural exogenous protease digestion either offered through soil exposure of the silk based plastics or via unique on-demand activation of proteases sequestered in the plastic materials to drive the degradation on-demand (hydration). The approaches described here demonstrate a new approach to bio-plastic formation and degradation from biopolymers that offers widespread options for future consumer materials with a focus on sustainability.