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1
Pavlova, Praskovya L., Andrey V. Minakov, Dmitriy V. Platonov, Vladimir A. Zhigarev, and Dmitriy V. Guzei. "Supercritical Fluid Application in the Oil and Gas Industry: A Comprehensive Review." Sustainability 14, no. 2 (January 9, 2022): 698. http://dx.doi.org/10.3390/su14020698.
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The unique properties of supercritical fluid technology have found wide application in various industry sectors. Supercritical fluids allow for the obtainment of new types of products with special characteristics, or development and design of technological processes that are cost-effective and friendly to the environment. One of the promising areas where supercritical fluids, especially carbon dioxide, can be used is the oil industry. In this regard, the present review article summarizes the results of theoretical and experimental studies of the use of supercritical fluids in the oil and gas industry for supercritical extraction in the course of oil refining, increasing oil recovery in the production of heavy oil, hydraulic fracturing, as well as processing and disposal of oil sludge and asphaltenes. At the end of the present review, the issue of the impact of supercritical fluid on the corrosion of oil and gas equipment is considered. It is found that supercritical fluid technologies are very promising for the oil industry, but supercritical fluids also have disadvantages, such as expansion or incompatibility with materials (for example, rubber).
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Heřmanská, Matylda, Barbara I. Kleine, and Andri Stefánsson. "Supercritical Fluid Geochemistry in Geothermal Systems." Geofluids 2019 (August 5, 2019): 1–14. http://dx.doi.org/10.1155/2019/6023534.
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Supercritical fluids exist in the roots of many active high-temperature geothermal systems. Utilization of such supercritical resources may multiply energy production from geothermal systems; yet, their occurrence, formation mechanism, and chemical properties are poorly constrained. Flow-through experiments at 260°C and 400-420°C were performed to study the chemical and mineralogical changes associated with supercritical fluid formation near shallow magmatic intrusions by conductive heating and boiling of conventional subcritical geothermal fluids. Supercritical fluids formed by isobaric heating of liquid geothermal water had similar volatile element concentrations (B, C, and S) as the subcritical water. In contrast, mineral-forming element concentrations (Si, Na, K, Ca, Mg, and Cl) in the supercritical fluid were much lower. The results are consistent with the observed mineral deposition of quartz, aluminum silicates, and minor amount of salts during boiling. Similar concentration patterns have been predicted from geochemical modeling and were observed at Krafla, Iceland, for the IDDP-1 supercritical fluid discharge. The experimental results confirm previous findings that supercritical fluids may originate from conductive heating of subcritical geothermal reservoir fluids characterized by similar or lower elemental concentrations with minor input of volcanic gas.
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Sedunov, Boris I. "Structural Transition in Supercritical Fluids." Journal of Thermodynamics 2011 (October 10, 2011): 1–5. http://dx.doi.org/10.1155/2011/194353.
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The extension of the saturation curve on the PT diagram in the supercritical region for a number of monocomponent supercritical fluids by peak values for different thermophysical properties, such as heat capacities and and compressibility has been studied. These peaks signal about some sort of fluid structural transition in the supercritical region. Different methods give similar but progressively diverging curves for this transition. The zone of temperatures and pressures near these curves can be named as the zone of the fluid structural transition. The outstanding properties of supercritical fluids in this zone help to understand the physical sense of the fluid structural transition.
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Orlovic, Aleksandar, and Dejan Skala. "Materials processing using supercritical fluids." Chemical Industry 59, no. 9-10 (2005): 213–23. http://dx.doi.org/10.2298/hemind0510213o.
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One of the most interesting areas of supercritical fluids applications is the processing of novel materials. These new materials are designed to meet specific requirements and to make possible new applications in Pharmaceuticals design, heterogeneous catalysis, micro- and nano-particles with unique structures, special insulating materials, super capacitors and other special technical materials. Two distinct possibilities to apply supercritical fluids in processing of materials: synthesis of materials in supercritical fluid environment and/or further processing of already obtained materials with the help of supercritical fluids. By adjusting synthesis parameters the properties of supercritical fluids can be significantly altered which further results in the materials with different structures. Unique materials can be also obtained by conducting synthesis in quite specific environments like reversed micelles. This paper is mainly devoted to processing of previously synthesized materials which are further processed using supercritical fluids. Several new methods have been developed to produce micro- and nano-particles with the use of supercritical fluids. The following methods: rapid expansion of supercritical solutions (RESS) supercritical anti-solvent (SAS), materials synthesis under supercritical conditions and encapsulation and coating using supercritical fluids were recently developed.
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Khetsuriani, N., K. Karchkhadze, V. Tsitsishvili, and K. Goderdzishvili. "PRODUCTION OF BIODIESEL USING SUPERCRITICAL FLUIDS TECHNOLOGY." Chemical Problems 15, no. 1 (2017): 21–25. http://dx.doi.org/10.32737/2221-8688-2017-1-21-25.
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Madana Gopal, Jaya Vignesh, Robert Morgan, Guillaume De Sercey, and Konstantina Vogiatzaki. "Overview of Common Thermophysical Property Modelling Approaches for Cryogenic Fluid Simulations at Supercritical Conditions." Energies 16, no. 2 (January 12, 2023): 885. http://dx.doi.org/10.3390/en16020885.
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Computational Fluid Dynamics (CFD) frameworks of supercritical cryogenic fluids need to employ Real Fluid models such as cubic Equations of State (EoS) to account for thermal and inertial driven mechanisms of fluid evolution and disintegration. Accurate estimation of the non-linear variation in density, thermodynamic and transport properties is required to computationally replicate the relevant thermo and fluid dynamics involved. This article reviews the availability, performance and the implementation of common Real Fluid EoS and data-based models in CFD studies of supercritical cryogenic fluids. A systematic analysis of supercritical cryogenic fluid (N2, O2 and CH4) thermophysical property predictions by cubic (PR and SRK) and non-cubic (SBWR) Real Fluid EoS, along with Chung’s model, reveal that: (a) SRK EoS is much more accurate than PR at low temperatures of liquid phase, whereas PR is more accurate at the pseudoboiling region and (b) SBWR EoS is more accurate than PR and SRK despite requiring the same input parameters; however, it is limited by the complexity in thermodynamic property estimation. Alternative data-based models, such as tabulation and polynomial methods, have also been shown to be reliably employed in CFD. At the end, a brief discussion on the thermophysical modelling of cryogenic fluids affected by quantum effects is included, in which the unsuitability of the common real fluid EoS models for the liquid phase of such fluids is presented.
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Shen, Yunqi, Zhiwen Hu, Xin Chang, and Yintong Guo. "Experimental Study on the Hydraulic Fracture Propagation in Inter-Salt Shale Oil Reservoirs." Energies 15, no. 16 (August 15, 2022): 5909. http://dx.doi.org/10.3390/en15165909.
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In response to the difficulty of fracture modification in inter-salt shale reservoirs and the unknown pattern of hydraulic fracture expansion, corresponding physical model experiments were conducted to systematically study the effects of fracturing fluid viscosity, ground stress and pumping displacement on hydraulic fracture expansion, and the latest supercritical CO2 fracturing fluid was introduced. The test results show the following. (1) The hydraulic fractures turn and expand when they encounter the weak surface of the laminae. The fracture pressure gradually increases with the increase in fracturing fluid viscosity, while the fracture pressure of supercritical CO2 is the largest and the fracture width is significantly lower than the other two fracturing fluids due to the high permeability and poor sand-carrying property. (2) Compared with the other two conventional fracturing fluids, under the condition of supercritical CO2 fracturing fluid, the increase in ground stress leads to the increase in inter-salt. (3) Compared with the other two conventional fracturing fluids, under the conditions of supercritical CO2 fracturing fluid, the fracture toughness of shale increases, the fracture pressure increases, and the fracture network complexity decreases as well. (4) With the increase in pumping displacement, the fracture network complexity increases, while the increase in the displacement of supercritical CO2 due to high permeability leads to the rapid penetration of inter-salt shale hydraulic fractures to the surface of the specimen to form a pressure relief zone; it is difficult to create more fractures with the continued injection of the fracturing fluid, and the fracture network complexity decreases instead.
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Demirbaş, A. "Supercritical fluid extraction and chemicals from biomass with supercritical fluids." Energy Conversion and Management 42, no. 3 (February 2001): 279–94. http://dx.doi.org/10.1016/s0196-8904(00)00059-5.
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Pucciarelli, Andrea, Sara Kassem, and Walter Ambrosini. "Overview of a Theory for Planning Similar Experiments with Different Fluids at Supercritical Pressure." Energies 14, no. 12 (June 21, 2021): 3695. http://dx.doi.org/10.3390/en14123695.
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The recent advancements achieved in the development of a fluid-to-fluid similarity theory for heat transfer with fluids at supercritical pressures are summarised. The prime mover for the development of the theory was the interest in the development of Supercritical Water nuclear Reactors (SCWRs) in the frame of research being developed worldwide; however, the theory is general and can be applied to any system involving fluids at a supercritical pressure. The steps involved in the development of the rationale at the basis of the theory are discussed and presented in a synthetic form, highlighting the relevance of the results achieved so far and separately published elsewhere, with the aim to provide a complete overview of the potential involved in the application of the theory. The adopted rationale, completely different from the ones in the previous literature on the subject, was based on a specific definition of similarity, aiming to achieve, as much as possible, similar distributions of enthalpies and fluid densities in a duct containing fluids at a supercritical pressure. This provides sufficient assurance that the complex phenomena governing heat transfer in the addressed conditions, which heavily depend on the changes in fluid density and in other thermophysical properties along and across the flow duct, are represented in sufficient similarity. The developed rationale can be used for planning possible counterpart experiments, with the aid of supporting computational fluid-dynamic (CFD) calculations, and it also clarifies the role of relevant dimensionless numbers in setting up semi-empirical correlations for heat transfer in these difficult conditions, experiencing normal, enhanced and deteriorated regimes. This paper is intended as a contribution to a common reflection on the results achieved so far in view of the assessment of a sufficient body of knowledge and understanding to base successful predictive capabilities for heat transfer with fluids at supercritical pressures.
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Ruiz, Helga K., Dolores R. Serrano, Lourdes Calvo, and Albertina Cabañas. "Current Treatments for COVID-19: Application of Supercritical Fluids in the Manufacturing of Oral and Pulmonary Formulations." Pharmaceutics 14, no. 11 (November 4, 2022): 2380. http://dx.doi.org/10.3390/pharmaceutics14112380.
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Even though more than two years have passed since the emergence of COVID-19, the research for novel or repositioned medicines from a natural source or chemically synthesized is still an unmet clinical need. In this review, the application of supercritical fluids to the development of novel or repurposed medicines for COVID-19 and their secondary bacterial complications will be discussed. We envision three main applications of the supercritical fluids in this field: (i) drug micronization, (ii) supercritical fluid extraction of bioactives and (iii) sterilization. The supercritical fluids micronization techniques can help to improve the aqueous solubility and oral bioavailability of drugs, and consequently, the need for lower doses to elicit the same pharmacological effects can result in the reduction in the dose administered and adverse effects. In addition, micronization between 1 and 5 µm can aid in the manufacturing of pulmonary formulations to target the drug directly to the lung. Supercritical fluids also have enormous potential in the extraction of natural bioactive compounds, which have shown remarkable efficacy against COVID-19. Finally, the successful application of supercritical fluids in the inactivation of viruses opens up an opportunity for their application in drug sterilization and in the healthcare field.
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Tian, Jie, Wende Yan, Zhilin Qi, Shiwen Huang, Yingzhong Yuan, and Mingda Dong. "Cyclic Supercritical Multi-Thermal Fluid Stimulation Process: A Novel Improved-Oil-Recovery Technique for Offshore Heavy Oil Reservoir." Energies 15, no. 23 (December 4, 2022): 9189. http://dx.doi.org/10.3390/en15239189.
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Cyclic supercritical multi-thermal fluid stimulation (CSMTFS) is a novel technology that can efficiently recover heavy oil, while the heating effect, production and heat loss characteristics of CSMTFS have not been discussed. In this study, a physical simulation experiment of CSMTFS is conducted with a three-dimensional experimental system. The results of the study indicate that the whole process of CSMTFS can be divided into four stages, namely, the preheating stage, production increase stage, production stable stage and production decline stage, of which the production stable stage is the main oil production stage, and the production decline stage is the secondary oil production stage. In the first two stages of the CSMTFS process, there is no supercritical multi-thermal fluid chamber, and only a relatively small supercritical multi-thermal fluid chamber is formed in the last stage of the CSMTFS process. Out of the supercritical multi-thermal fluid chamber, supercritical water in the thermal fluids condensates to hot water and flows downward to heat the subjacent oil layer. At the same time, the non-condensate gas in the thermal fluids accumulates to the upper part of the oil layer and reduces heat loss. The analysis of heat loss shows that the heat loss rate gradually increases at first and then tends to be stable. Compared with conventional thermal fluid, the CSMTFS can more effectively reduce heat loss. The enthalpy value of supercritical multi-thermal fluid is significantly increased compared with that of multi-thermal fluid, which effectively solves the problem of insufficient heat carrying capacity of multi-thermal fluid. Overall, cyclic supercritical multi-thermal fluid stimulation can effectively solve the problems of conventional heavy oil thermal recovery technology in offshore heavy oil recovery; it is indeed a new improved-oil-recovery technique for offshore heavy oil. The findings of this study can help in better understanding the cyclic supercritical multi-thermal fluid stimulation process. This study is significant and helpful for application of CSMTFS technology in heavy oil recovery.
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Kulazynski, Marek, Marek Stolarski, Hanna Faltynowicz, Beata Narowska, Lukasz Swiatek, and Marcin Lukaszewicz. "Supercritical Fluid Extraction of Vegetable Materials." Chemistry & Chemical Technology 10, no. 4s (December 25, 2016): 637–43. http://dx.doi.org/10.23939/chcht10.04si.637.
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The paper presents the base and conditions for the extraction of organic materials with solvents in the supercritical state with particular attention to use of CO2 as the extraction agent. The advantages and disadvantages of this process are described. The examples of extraction of organic materials using supercritical of CO2 are presented.
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Zuddas, Pierpaolo, Stefano Salvi, Olivier Lopez, Giovanni De Giudici, and Paolo Censi. "Escape of Supercritical-CO2 Fluids Trapped in Calcite Nano-metric Pores." E3S Web of Conferences 98 (2019): 01056. http://dx.doi.org/10.1051/e3sconf/20199801056.
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Flow of supercritical CO2-bearing fluids through a rock is a fundamental phenomenon which acts upon a great many geological processes ranging from seismic activity to formation of ore deposits. Atomic Force Microscopy scanning experiments allowed us to infer movement of supercritical CO2-bearing fluids through calcite crystals and relate it to natural decrepitation of nanoscale fluid inclusions. Calculated velocities exceed the rate of diffusion predicated via current vacancy models by several orders of magnitude implying that CO2-rich fluid movement through micro and nano-pore space may presently be greatly underestimated.
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Knez, Zeljko. "Particle formation using supercritical fluids: A short review." Chemical Industry and Chemical Engineering Quarterly 12, no. 3 (2006): 141–46. http://dx.doi.org/10.2298/ciceq0603141k.
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Particle formation and the design of solid particles and powdery composites with unique properties is at the moment one of major the developments of supercritical fluid (synonyms: dense gases, dense fluids, high pressure) applications. Conventional well-known processes for the particle-size redistribution of solid materials are crushing and grinding (which for some compounds are carried out at cryogenic temperatures), air micronization sublimation, and recrystallization from solution. There are several problems associated with the above-mentioned processes. Some substances are unstable under conventional milling conditions, in recrystallization processes the product is contaminated with solvent, and waste solvent streams are produced. The application of supercritical fluids may overcome the drawbacks of conventional processes, and powders and composites with special characteristics can be produced. Several processes for the formation and design of solid particles using dense gases have been studied intensively. The unique thermodynamic and fluid-dynamic properties of supercritical fluids can also be used for the impregnation of solid particles, for the formation of solid powderous emulsions, particle coatings, e.g. for the formation of solids with unique properties for use in different applications. This review will focus on the fundamentals and on recent advances of particle formation and design processes using supercritical fluids, on their applications and the technological advantages and disadvantages of various processes.
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Skala, Dejan, Irena Zizovic, and Sladjana Gavrancic. "Supercritical fluid extraction: Application in the food industry." Chemical Industry 56, no. 5 (2002): 179–90. http://dx.doi.org/10.2298/hemind0205179s.
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Supercritical fluid extraction is an extraction process realized with supercritical fluids, which are at a temperature and pressure above their critical temperature and critical pressure. This process has shown to be very efficient one for the isolation of different substances of medium molecular weights and molecules of relatively low polarity. The solubility of more polar substances in supercritical fluids can be improved by the addition of small amounts of other polar solvents (cosolvent) to the supercritical fluids, which is the main solvent in extraction process. The advantage of supercritical extraction compared to other extraction procedures (the application of classical organic solvents hydrodistillation, distillation with steam) is that SFE is usually performed at moderate temperature (e.g. with SF CO2 at 40-70?C) so it can be applied for the separation of different substances which are thermally unstable and have a larger vapour pressure. All of these facts indicate that SFE is of special interest for the food and pharmaceutical industry.
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Knox, Dana E. "Solubilities in supercritical fluids." Pure and Applied Chemistry 77, no. 3 (January 1, 2005): 513–30. http://dx.doi.org/10.1351/pac200577030513.
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Solubilities in supercritical fluids are of great importance in a wide variety of applications. These applications include: production of controlled drug delivery systems, powder processing, pollution prevention and remediation, methods for spraying paints and coatings, precipitation/crystallization processes, bioseparations, and food processing. Examples of some of these applications will be given.Supercritical fluid processes make use of the significant variation of solubility with pressure when the solvent is a supercritical fluid. This permits the accomplishment of many processes that would be otherwise very difficult to achieve. To fully understand the benefits of such processes, one must understand the phase behavior of such systems. The types of phase behavior that can be observed will be discussed, along with the ways that this behavior can be used to modify solubilities in such fluids.There have been many methods proposed for the experimental determination of solubilities in supercritical fluids. These will be reviewed in general, and recommendations for preferred methods given.Solubilities in supercritical fluids can be correlated and predicted by making use of thermodynamic calculations involving equations of state, as well as by other methods. The various methods will be reviewed, and recommendations given for various applications.
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Li, Yung-Ming, Jane-Sunn Liaw, and Chi-Chuan Wang. "A Criterion of Heat Transfer Deterioration for Supercritical Organic Fluids Flowing Upward and Its Heat Transfer Correlation." Energies 13, no. 4 (February 22, 2020): 989. http://dx.doi.org/10.3390/en13040989.
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The main objective of this study was to develop the supercritical heat transfer correlation applicable for organic fluids when flowing upward in smooth tubes based on the available experimental data. The organic fluids contain R-22, R-134a, R-245fa and Ethanol and the associated heat transfer characteristics were compared with non-organic fluids like water and carbon-dioxide (CO2). It was found that the limit heat flux may result in heat transfer deterioration (HTD) of organic fluid and the corresponding values are much smaller than water or CO2. A new criterion to predict the HTD was developed and this criterion yields the best predictive ability against database. It was found that HTD occurs can be well described by the acceleration parameter evaluated at the wall condition rather than at bulk condition. For estimation of the supercritical heat transfer coefficient (HTC) for organic fluid, the present study proposes a new correlation with a physically based correction factor, which gives satisfactory predictions against the HTC of supercritical organic fluid. The new correlation can offer the smallest average deviation of 0.007 and standard deviation of 0.181 among the existing correlations.
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Wang, Ming Lu, and Wei Qiang Wang. "Study on the Strength of Textile during the Process of Supercritical Fluids Spray Dyeing." Advanced Materials Research 951 (May 2014): 41–44. http://dx.doi.org/10.4028/www.scientific.net/amr.951.41.
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The deformation and tension of textile between two dyeing roller during supercritical fluid spray dyeing was studied in this paper. The parameter equations were built by introduced the transformation parameter based on the mechanical equilibrium of infinitesimal element at the premise of considering the elasticity of textile. The results show that the internal stress of textile is far less than the tensile strength of the fabric, and the operating parameters of supercritical fluids spray dyeing has obvious effect on the deformation of textile. The simulating analysis may provide a theoretical basis and guidance for the actual process of supercritical fluid spray dyeing.
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Tian, Zhen, Nai Ci Bing, Ye Zhang, Ling Ling Wang, and Wei Qiao. "Supercritical Solvent Impregnation in Controlled-Release Drugs." Advanced Materials Research 152-153 (October 2010): 1462–65. http://dx.doi.org/10.4028/www.scientific.net/amr.152-153.1462.
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In the field of pharmaceutical industry, the controlled-release drugs have received considerable attention in the last years. Impregnation using supercritical fluid technology has already proven its feasibility in the preparation of controlled release systems. The use of supercritical fluids such as supercritical CO2 has provided a ‘clean’ and effective alternative to traditional methods of drug releasing and polymer processes. In particular, scCO2 has a number of unique properties that make it possible to process both bioactive molecules and amorphous polymers without using toxic organic solvents or elevated temperatures. A high purity product, free of residual solvents is obtained, since no organic solvents are involved in the impregnation process. Here, we review the advantages of supercritical fluid and the preparation of controlled-release drugs by supercritical solvent impregnation.
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Craig, Walter, and Peter Sternberg. "Comparison principles for free-surface flows with gravity." Journal of Fluid Mechanics 230 (September 1991): 231–43. http://dx.doi.org/10.1017/s0022112091000770.
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This article considers certain two-dimensional, irrotational, steady flows in fluid regions of finite depth and infinite horizontal extent. Geometrical information about these flows and their singularities is obtained, using a variant of a classical comparison principle. The results are applied to three types of problems: (i) supercritical solitary waves carrying planing surfaces or surfboards, (ii) supercritical flows past ship hulls and (iii) supercritical interfacial solitary waves in systems consisting of two immiscible fluids.
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Marcus, Yizhak. "Some Advances in Supercritical Fluid Extraction for Fuels, Bio-Materials and Purification." Processes 7, no. 3 (March 13, 2019): 156. http://dx.doi.org/10.3390/pr7030156.
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Supercritical fluids are used for the extraction of desired ingredients from natural materials, but also for the removal of undesired and harmful ingredients. In this paper, the pertinent physical and chemical properties of supercritical water, methanol, ethanol, carbon dioxide, and their mixtures are provided. The methodologies used with supercritical fluid extraction are briefly dealt with. Advances in the application of supercritical extraction to fuels, the gaining of antioxidants and other useful items from biomass, the removal of undesired ingredients or contaminants, and the preparation of nanosized particles of drugs are described.
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O'Neill, Mark L., Peeter Kruus, and Robert C. Burk. "Solvatochromic parameters and solubilities in supercritical fluid systems." Canadian Journal of Chemistry 71, no. 11 (November 1, 1993): 1834–40. http://dx.doi.org/10.1139/v93-229.
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Spectroscopic studies of the compound 2-nitroanisole in supercritical fluids CO2 and N2O show that π* values vary linearly with density. The solubility trends in these single component supercritical fluid solvents qualitatively followed the trends in solvent power predicted from π*. However, the relative solvent power predicted for CO2 and N2O based on π* resulted in an opposite order to what was determined experimentally through solubility measurements. The π* parameter may be of some use for solubility prediction if only a limited set of solute–solvent systems are considered. Measurements of π*, especially those in binary supercritical fluid solvents, suggest that π* could be a valuable tool for probing the solute-organized cybotactic region.
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Епифанов, Е. О., А. О. Рыбалтовский, Н. В. Минаев, and В. И. Юсупов. "Особенности фокусировки лазерного излучения в сверхкритическом СО-=SUB=-2-=/SUB=-." Письма в журнал технической физики 49, no. 2 (2023): 44. http://dx.doi.org/10.21883/pjtf.2023.02.54286.19362.
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features of the phenomena of a laser nanosecond radiation In supercritical carbon dioxide are revealed. It is shown that the presence of a supercritical fluid leads to the expansion of the structures formed on the target in comparison with the air media. It has been suggested that the resulting magnification effect is due to the defocusing of the system, which causes the formation of the lens impact. Obtaining useful results is possible with the use of various technologies of laser ablation and microstructuring in supercritical fluids.
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Gamse, Thomas. "Industrial applications and current trends in supercritical fluid technologies." Chemical Industry 59, no. 9-10 (2005): 207–12. http://dx.doi.org/10.2298/hemind0510207g.
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Supercritical fluids have a great potential for wide fields of processes Although CO2 is still one of the most used supercritical gases, for special purposes propane or even fluorinated-chlorinated fluids have also been tested. The specific characteristics of supercritical fluids behaviour were analyzed such as for example the solubilities of different components and the phase equilibria between the solute and solvent. The application at industrial scale (decaffeinating of tea and coffee, hop extraction or removal of pesticides from rice), activity in supercritical extraction producing total extract from the raw material or different fractions by using the fractionated separation of beverages (rum, cognac, whisky, wine, beer cider), of citrus oils and of lipids (fish oils, tall oil) were also discussed. The main interest is still for the extraction of natural raw materials producing food ingredients, nutraceuticals and phytopharmaceuticals but also cleaning purposes were tested such as the decontamination of soils the removal of residual solvents from pharmaceutical products, the extraction of flame retardants from electronic waste or precision degreasing and cleaning of mechanical and electronic parts. An increasing interest obviously exists for impregnation purposes based on supercritical fluids behaviour, as well as for the dying of fibres and textiles. The production of fine particles in the micron and submicron range, mainly for pharmaceutical products is another important application of supercritical fluids. Completely new products can be produced which is not possible under normal conditions. Supercritical fluid technology has always had to compete with the widespread opinion that these processes are very expensive due to very high investment costs in comparison with classical low-pressure equipment. Thus the opinion is that these processes should be restricted to high-added value products. A cost estimation for different plant sizes and different applications was also analyzed.
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Soh, Soon Hong, and Lai Yeng Lee. "Microencapsulation and Nanoencapsulation Using Supercritical Fluid (SCF) Techniques." Pharmaceutics 11, no. 1 (January 5, 2019): 21. http://dx.doi.org/10.3390/pharmaceutics11010021.
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The unique properties of supercritical fluids, in particular supercritical carbon dioxide (CO2), provide numerous opportunities for the development of processes for pharmaceutical applications. One of the potential applications for pharmaceuticals includes microencapsulation and nanoencapsulation for drug delivery purposes. Supercritical CO2 processes allow the design and control of particle size, as well as drug loading by utilizing the tunable properties of supercritical CO2 at different operating conditions (flow ratio, temperature, pressures, etc.). This review aims to provide a comprehensive overview of the processes and techniques using supercritical fluid processing based on the supercritical properties, the role of supercritical carbon dioxide during the process, and the mechanism of formulation production for each process discussed. The considerations for equipment configurations to achieve the various processes described and the mechanisms behind the representative processes such as RESS (rapid expansion of supercritical solutions), SAS (supercritical antisolvent), SFEE (supercritical fluid extraction of emulsions), PGSS (particles from gas-saturated solutions), drying, and polymer foaming will be explained via schematic representation. More recent developments such as fluidized bed coating using supercritical CO2 as the fluidizing and drying medium, the supercritical CO2 spray drying of aqueous solutions, as well as the production of microporous drug releasing devices via foaming, will be highlighted in this review. Development and strategies to control and optimize the particle morphology, drug loading, and yield from the major processes will also be discussed.
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Vizuete, Ricardo. "Supercritical fluid extraction." Medwave 20, S1 (February 28, 2020): eCS40-eCS40. http://dx.doi.org/10.5867/medwave.2020.s1.cs40.
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Yang, Jun Lan, Yi Tai Ma, and Min Xia Li. "Comparative Analysis of Heat Transfer Characteristics for CO2 and Conventional Refrigerants." Applied Mechanics and Materials 130-134 (October 2011): 1306–9. http://dx.doi.org/10.4028/www.scientific.net/amm.130-134.1306.
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s: The obvious characteristics of transcritical CO2 cycle are that the heat rejection process takes place in the supercritical region (about 8-12Mpa). The heat transfer features of CO2 under supercritical pressure are different from those of the conventional refrigerants. And the heat transfer performances comparison study for supercritical CO2 fluid and the conventional refrigerants are carried out by means of thermo-physical properties analog analysis and experimental results quantitative comparison. The special properties variation of supercritical CO2 fluid makes its heat transfer performance different from the conventional fluids. From the view of properties analysis and quantitative comparison, the heat transfer performance of supercritical CO2 is equivalent to the condensation heat transfer of conventional refrigerants. Although the condensation coefficient is very large since there is phase change and latent heat variation in the condensation process, there is liquid film thermal resistance. While in the supercritical CO2 cooling process, there is no liquid film in existence and the thickness of the boundary layer is very thin. The heat transfer temperature difference is very large, so the heat transfer performance in the supercritical CO2 cooling process is equivalent to that of the condensation heat transfer.
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Abraham, Martin A. "Supercritical fluids." Environmental Progress 17, no. 4 (1998): W3. http://dx.doi.org/10.1002/ep.670170402.
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Chen, Run. "Interaction between Supercritical CO2 and Coal Petrography." Advanced Materials Research 616-618 (December 2012): 306–9. http://dx.doi.org/10.4028/www.scientific.net/amr.616-618.306.
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CO2enhanced CBM recovery(CO2-ECBM) is an important way for reducing CO2emission into atmosphere and enhancing coal-bed methane (CBM) recovery. The interaction between supercritical CO2and coal petrography has been investigated since the 1990s. Advances in the interaction between supercritical CO2and coal petrography are reviewed in light of certain aspects, such as the competitive multi-component gas adsorption, sorption-induced coal swelling/shrinkage and the fluid-solid coupling between fluids(such as gas, liquid and supercritical fluid) and coal petrography. It is suggested that a comprehensive feasibility demonstration is necessary for a successful application of the technology for CO2-ECBM. At the same time, it also indicated that there are some questions must be discussed in future, such as the influences on pore structure, coal adsorptivity and permeability of the reaction of ScCO2-H2O and rock and small organic matters are extracted by supercritical CO2.
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Liao, Shen-Kung, and Pi-Shiun Chang. "“Special Issue—Supercritical Fluids” Literatures on Dyeing Technique of Supercritical Fluid Carbon Dioxide." American Journal of Analytical Chemistry 03, no. 12 (2012): 923–30. http://dx.doi.org/10.4236/ajac.2012.312a122.
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Niemeyer, Emily D., Richard A. Dunbar, and Frank V. Bright. "On the Local Environment Surrounding Pyrene in Near- and Supercritical Water." Applied Spectroscopy 51, no. 10 (October 1997): 1547–53. http://dx.doi.org/10.1366/0003702971939091.
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We use steady-state and time-resolved fluorescence spectroscopy to probe local solvent–solute interactions between pyrene (the solute) and supercritical water (SCW). Toward this end, we have developed a new fiber-optic-based titanium high-pressure optical cell which can withstand the temperatures and pressure needed to generate supercritical water. Static fluorescence measurements indicate that there is an increase in the local water density surrounding the pyrene molecules (clustering) up to five times the bulk fluid density. This extent of clustering is most prevalent at about one-half the critical density. Consistent with previous work on more mild supercritical fluids (e.g., CO2, CF3H, C2H6), the extent of this solute–fluid clustering decreases as the system temperature and pressure are increased. Time-resolved fluorescence measurements show that the excited-state decay kinetics are exponentially activated and not themselves affected by this solute–fluid clustering process.
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Vitale, Salvatore, Tim A. Albring, Matteo Pini, Nicolas R. Gauger, and Piero Colonna. "Fully turbulent discrete adjoint solver for non-ideal compressible flow applications." Journal of the Global Power and Propulsion Society 1 (November 22, 2017): Z1FVOI. http://dx.doi.org/10.22261/jgpps.z1fvoi.
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Abstract Non-Ideal Compressible Fluid-Dynamics (NICFD) has recently been established as a sector of fluid mechanics dealing with the flows of dense vapors, supercritical fluids, and two-phase fluids, whose properties significantly depart from those of the ideal gas. The flow through an Organic Rankine Cycle (ORC) turbine is an exemplary application, as stators often operate in the supersonic and transonic regime, and are affected by NICFD effects. Other applications are turbomachinery using supercritical CO2 as working fluid or other fluids typical of the oil and gas industry, and components of air conditioning and refrigeration systems. Due to the comparably lower level of experience in the design of this fluid machinery, and the lack of experimental information on NICFD flows, the design of the main components of these processes (i.e., turbomachinery and nozzles) may benefit from adjoint-based automated fluid-dynamic shape optimization. Hence, this work is related to the development and testing of a fully-turbulent adjoint method capable of treating NICFD flows. The method was implemented within the SU2 open-source software infrastructure. The adjoint solver was obtained by linearizing the discretized flow equations and the fluid thermodynamic models by means of advanced Automatic Differentiation (AD) techniques. The new adjoint solver was tested on exemplary turbomachinery cases. Results demonstrate the method effectiveness in improving simulated fluid-dynamic performance, and underline the importance of accurately modeling non-ideal thermodynamic and viscous effects when optimizing internal flows influenced by NICFD phenomena.
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McNally, Mary Ellen P. "Method Development in Supercritical Fluid Extraction." Journal of AOAC INTERNATIONAL 79, no. 2 (March 1, 1996): 380–88. http://dx.doi.org/10.1093/jaoac/79.2.380.
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Abstract When using supercritical fluid extraction (SFE), a variety of chemical and physical parameter interactions must be considered in developing a sample preparation method. Those interactions, especially for an analyst who is unfamiliar with the properties and potentials of supercritical fluids, can make routine analytical method development quite rigorous. This paper is meant as a guide for a novice user of SFE. It illustrates a logical scheme to consider when removing an analyte from a difficult matrix.
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Gutierrez, Marte, Daisuke Katsuki, and Abdulhadi Almrabat. "Seismic velocity change in sandstone during CO2 injection." E3S Web of Conferences 205 (2020): 02001. http://dx.doi.org/10.1051/e3sconf/202020502001.
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This paper presents analytical and experimental studies of the effects of supercritical CO2 injection on the seismic velocity of sandstone initially saturated with saline water. The analytical model is based on poroelasticity theory, particularly the application of the Biot-Gassmann substitution theory in the modeling of the acoustic velocity of porous rocks containing two-phase immiscible fluids. The experimental study used a high pressure and high temperature triaxial cell to clarify the seismic response of samples of Berea sandstone to supercritical CO2 injection under deep saline aquifer conditions. Measured ultrasonic wave velocity changes during CO2 injection in the sandstone sample showed the effects of pore fluid distribution in the seismic velocity of porous rocks. CO2 injection was shown to decrease the P-wave velocity with increasing CO2 saturation whereas the S-wave velocity was almost constant. The results confirm that the Biot-Gassmann theory can be used to model the changes in the acoustic P-wave velocity of sandstone containing different mixtures of supercritical CO2 and saline water provided the distribution of the two fluids in the sandstone pore space is accounted for in the calculation of the pore fluid bulk modulus.
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Martín, Ángel, Salima Varona, Alexander Navarrete, and María José Cocero. "Encapsulation and Co-Precipitation Processes with Supercritical Fluids: Applications with Essential Oils." Open Chemical Engineering Journal 4, no. 1 (March 25, 2010): 31–41. http://dx.doi.org/10.2174/1874123101004010031.
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Essential oils have important commercial applications as preservatives and flavours, and more recently as natural antimicrobial agents. These applications require a suitable formulation constituted by biodegradable compounds that protect the essential oil from degradation and evaporation at the same time that allows for a sustained release. Microcapsules of biopolymers loaded with essential oils meet these requirements. Such microcapsules can be prepared with different processes such as spray-drying, freeze-drying and coacervation, and supercritical fluids are an advantageous medium for this purpose. Some supercritical fluid-based precipitation processes have already been applied to produce these microcapsules. Amongst them, the results obtained with Particles from Gas Saturated Solutions (PGSS), PGSS-drying and Concentrated Powder Form (CPF) processes are particularly promising. Recent developments in the preparation of formulations with supercritical fluids include the preparation of liposomes and micelles, which can be suitable carriers for essential oils.
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Olszak, Artur, Karol Osowski, Ireneusz Musiałek, Elżbieta Rogoś, Andrzej Kęsy, and Zbigniew Kęsy. "Application of Plant Oils as Ecologically Friendly Hydraulic Fluids." Applied Sciences 10, no. 24 (December 18, 2020): 9086. http://dx.doi.org/10.3390/app10249086.
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This paper presents the results of physicochemical and tribological tests of vegetable oils obtained by the supercritical fluid extraction method from berry seeds. The research was conducted by using these oils as the raw material for the biodegradable hydraulic working fluids. The oils were assessed in terms of kinematic viscosity, anti-wear properties, resistance to oxidation and corrosive effects to copper and the pour point. The best results were achieved in the case of the blackcurrant seed oil. In order to confirm the practical possibility of using vegetable oils as working fluids for hydraulic couplings, experimental tests of the hydrodynamic clutch filled with blackcurrant seed oil were carried out. Based on the obtained research results, it was found that oils from berry plant seeds produced by supercritical extraction could be used in the future as potential working fluids for hydraulic systems.
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Žitek, Taja, Maja Leitgeb, Andrej Golle, Barbara Dariš, Željko Knez, and Maša Knez Hrnčič. "The Influence of Hemp Extract in Combination with Ginger on the Metabolic Activity of Metastatic Cells and Microorganisms." Molecules 25, no. 21 (October 28, 2020): 4992. http://dx.doi.org/10.3390/molecules25214992.
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This study presents an investigation of the anticancer and antimicrobial ability of a combination of ginger and cannabis extracts in different ratios (1:1, 7:3 and 3:7). Extracts were obtained using various methods (Soxhlet extractions, cold macerations, ultrasonic extractions and supercritical fluid extractions). The antioxidant activity and the presence of total phenols were measured in the extracts, and the effect of the application extracts in various concentrations (c = 50, 20, 10, 5, 1, 0.1, 0.01 mg/mL) on cells was investigated. Higher values of antioxidants were measured at the ratio where ginger was predominant, which is reflected in a higher concentration of total phenols. Depending on the polyphenol content, the extracts were most effective when prepared supercritically and ultrasonically. However, with respect to cell response, the ratio was shown to have no effect on inhibiting cancer cell division. The minimum concentration required to inhibit cancer cell growth was found to be 1 mg/mL. High-performance liquid chromatography (HPLC) analysis also confirmed the effectiveness of ultrasonic and supercritical fluid extraction, as their extracts reached higher cannabinoid contents. In both extractions, the cannabidiol (CBD) content was above 30% and the cannabidiolic acid (CBDA) content was above 45%. In the case of ultrasonic extraction, a higher quantity of cannabigerol (CBG) (5.75 ± 0.18) was detected, and in the case of supercritical fluid extraction, higher cannabichromene (CBC) (5.48 ± 0.13) content was detected, when compared to other extraction methods. The antimicrobial potential of extracts prepared with ultrasonic and supercritical extractions on three microorganisms (Staphylococcus aureus, Escherichia coli and Candida albicans) was checked. Ginger and cannabis extract show better growth inhibition of microorganisms in cannabis-dominated ratios for gram-positive bacterium S. aureus, MIC = 9.38 mg/mL, for gram-negative bacterium E. coli, MIC > 37.5 mg/mL and for the C. albicans fungus MIC = 4.69 mg/mL. This suggests guidelines for further work: a 1: 1 ratio of ginger and hemp will be chosen in a combination with supercritical and ultrasonic extraction.
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Yang, Jyisy, and Peter R. Griffiths. "Prediction of the Solubility in Supercritical Fluids Based on Supercritical Fluid Chromatography Retention Times." Analytical Chemistry 68, no. 14 (January 1996): 2353–60. http://dx.doi.org/10.1021/ac960371r.
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Wang, Hai, Melvin Tucker, and Yun Ji. "Recent Development in Chemical Depolymerization of Lignin: A Review." Journal of Applied Chemistry 2013 (July 10, 2013): 1–9. http://dx.doi.org/10.1155/2013/838645.
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This article reviewed recent development of chemical depolymerization of lignins. There were five types of treatment discussed, including base-catalyzed, acid-catalyzed, metallic catalyzed, ionic liquids-assisted, and supercritical fluids-assisted lignin depolymerizations. The methods employed in this research were described, and the important results were marked. Generally, base-catalyzed and acid-catalyzed methods were straightforward, but the selectivity was low. The severe reaction conditions (high pressure, high temperature, and extreme pH) resulted in requirement of specially designed reactors, which led to high costs of facility and handling. Ionic liquids, and supercritical fluids-assisted lignin depolymerizations had high selectivity, but the high costs of ionic liquids recycling and supercritical fluid facility limited their applications on commercial scale biomass treatment. Metallic catalyzed depolymerization had great advantages because of its high selectivity to certain monomeric compounds and much milder reaction condition than base-catalyzed or acid-catalyzed depolymerizations. It would be a great contribution to lignin conversion if appropriate catalysts were synthesized.
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Kong, Chang Yi, Yuuki Shiratori, Takeshi Sako, and Futoshi Iwata. "A Green Approach for Highly Reduction of Graphene Oxide by Supercritical Fluid." Advanced Materials Research 1004-1005 (August 2014): 1013–16. http://dx.doi.org/10.4028/www.scientific.net/amr.1004-1005.1013.
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A green method to synthesize the reduced graphene oxide using supercritical fluid has been developed, which is an environmentally friendly and efficient route. The reduced graphene oxide has been examined by X-ray diffraction, Raman spectroscopy. We have also studied the effects of reduction temperatures and supercritical fluids on the electrical properties of reduced graphene oxide. It was found that ethanol has higher reducing capability than CO2at all temperatures (200 - 400°C) examined in this study for graphene oxide reduction. As a result, reduced graphene oxide (6300 S/m) from supercritical ethanol treatment has 5 times as high conductivity as that from supercritical CO2treatment at the reduction temperature of 400°C. This green process is applicable for large scale production of reduced graphene oxides for various practical applications.
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Koel, M., S. Ljovin, K. Hollis, and J. Rubin. "Using neoteric solvents in oil shale studies." Pure and Applied Chemistry 73, no. 1 (January 1, 2001): 153–59. http://dx.doi.org/10.1351/pac200173010153.
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The liquefaction, gasification, and other chemical modifications of oil shale are challenging goals of chemistry and chemical engineering. The use of new solvent systems, such as supercritical fluids and ionic liquids, represents new avenues in the search of environmentally benign technologies. Supercritical fluid extraction (SFE) with carbon dioxide is particularly effective for the isolation of substances of medium molecular weight and relatively low polarity. At elevated temperatures it is possible to unite the breaking chemical bonds in the kerogen organic matter and convert the former into oil with extraction using supercritical fluids. Quantitative and qualitative information obtained at different temperatures during SFE is providing some insight into the speciation of hydrocarbons in geological samples. Ionic liquids were studied as potential solvents for kerogen extraction. However, these chemical processes are favored at elevated temperatures up to the thermal degradation temperature of kerogen, 400 C. There were observed significant differences in the chemical composition of extracted oil and from the oil from the classical semicoking process of oil shale. An additional application would be a combination of the two methodsthe use of supercritical carbon dioxide to recover nonvolatile organic compounds from room-temperature ionic liquid without using organic solvents.
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Branch, Jack A., and Philip N. Bartlett. "Electrochemistry in supercritical fluids." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 373, no. 2057 (December 28, 2015): 20150007. http://dx.doi.org/10.1098/rsta.2015.0007.
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A wide range of supercritical fluids (SCFs) have been studied as solvents for electrochemistry with carbon dioxide and hydrofluorocarbons (HFCs) being the most extensively studied. Recent advances have shown that it is possible to get well-resolved voltammetry in SCFs by suitable choice of the conditions and the electrolyte. In this review, we discuss the voltammetry obtained in these systems, studies of the double-layer capacitance, work on the electrodeposition of metals into high aspect ratio nanopores and the use of metallocenes as redox probes and standards in both supercritical carbon dioxide–acetonitrile and supercritical HFCs.
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Oman, Miha, Mojca Škerget, and Zeljko Knez. "Application of supercritical fluid extraction for separation of nutraceuticals and other phytochemicals from plant material." Macedonian Journal of Chemistry and Chemical Engineering 32, no. 1 (December 1, 2013): 183. http://dx.doi.org/10.20450/mjcce.2013.443.
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In present work a literature review of application of supercritical fluid extraction (SFE) for isolation of nutraceuticals and some other phytochemicals up to December of 2012 is presented. Manuscript provides knowledge of SFE processes and possible aplications of SFE for extraction of bioactive compounds which serve as nutraceuticals. Compounds are classified into groups based on their chemical nature (carotenoids, flavonoids and other phenolic compounds, essential oils, lipids and fatty acids, and alkaloids and other bioactive phytochemicals) and they are reviewed in tabular form along with plant material, from which they were extracted using supercritical fluids.
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Blitz, J. P., J. L. Fulton, and R. D. Smith. "Near- and Mid-Infrared Transmission Cells for the Study of Reverse Micelle Phases in Supercritical Fluids." Applied Spectroscopy 43, no. 5 (July 1989): 812–16. http://dx.doi.org/10.1366/0003702894202337.
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The design and construction of near- and mid-infrared transmission cells for the study of liquid, gaseous, and fluid systems at elevated pressures and temperatures are described. The cells can be used to pressures as high as 800 bar and temperatures exceeding 100°C. Typical spectra of reverse micelle phases in liquid propane and supercritical xenon through the near- and mid-infrared range are presented. The utility of applying FT-IR spectroscopy, and the transmission cells described here, to study reverse micelle and microemulsion phases in supercritical fluids is clearly demonstrated.
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Györke, Gábor, and Attila R. Imre. "Physical-chemical Background of the Potential Phase Transitions during Loss of Coolant Accidents in the Supercritical Water Loops of Various Generation IV Nuclear Reactor Types." Periodica Polytechnica Chemical Engineering 63, no. 2 (March 18, 2019): 333–39. http://dx.doi.org/10.3311/ppch.12770.
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Loss of coolant accidents (LOCA) are a serious type of accidents for nuclear reactors, when the integrity of the liquid-loop breaks. While in traditional pressurized water reactors, pressure drop can cause flash boiling, in Supercritical-Water Cooled reactors, the pressure drop can be terminated by processes with fast phase transition (flash boiling or steam collapse) causing pressure surge or the expansion can go smoothly to the dry steam region. Modelling the pressure drop of big and small LOCAs as isentropic and isenthalpic processes and replacing the existing reactor designs with a simplified supercritical loop, limiting temperatures for various outcomes will be given for 24.5 and 25 MPa initial pressure. Using the proposed method, similar accidents for chemical reactors and other equipment using supercritical fluids can be also analyzed, using only physical-chemical properties of the given supercritical fluid.
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Noyori, Ryoji. "Supercritical Fluids: Introduction." Chemical Reviews 99, no. 2 (February 1999): 353–54. http://dx.doi.org/10.1021/cr980085a.
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YAO, Makoto. "Supercritical Molecular Fluids." Review of High Pressure Science and Technology 18, no. 4 (2008): 328–34. http://dx.doi.org/10.4131/jshpreview.18.328.
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Su, Wei, Hongshuo Zhang, Yi Xing, Xinyan Li, Jiaqing Wang, and Changqing Cai. "A Bibliometric Analysis and Review of Supercritical Fluids for the Synthesis of Nanomaterials." Nanomaterials 11, no. 2 (January 28, 2021): 336. http://dx.doi.org/10.3390/nano11020336.
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Since the 1990s, supercritical fluids for the synthesis of nanomaterials have been paid more and more attention by researchers and have gradually become one of the most important ways to prepare nanomaterials. In this study, literature data on “supercritical fluids for the synthesis of nanomaterials” from 1998 to 2020 were obtained from the Web of Science database, and the data were processed and analyzed by the bibliometric method combined with Microsoft office 2019, Origin 2018, VOSviewer, and other software, so as to obtain the research status and development trend of “supercritical fluids for the synthesis of nanomaterials”. The results show that since literature on “supercritical fluids for the synthesis of nanomaterials” appeared for the first time in 1998, the number of articles published every year has risen. In terms of this field, China has become the second-largest publishing country after the United States, and China and the United States display a lot of cooperation and exchanges in this field. “Supercritical CO2”, “supercritical water”, “supercritical antisolvent”, “surface modification”, and so on have become the research hotspots of “supercritical fluids for the synthesis of nanomaterials”.
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Roth, Michal. "Cohesive Energy Densities Versus Internal Pressures of Near and Supercritical Fluids." Molecules 24, no. 5 (March 8, 2019): 961. http://dx.doi.org/10.3390/molecules24050961.
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Over half a century ago, Wiehe and Bagley suggested that a product of the internal pressure and molar volume of a liquid measures the energy of nonspecific intermolecular interactions whereas the cohesive energy reflects the total energy of intermolecular interactions in the liquid. This conjecture, however, has never been considered in connection with near and supercritical fluids. In this contribution, the cohesive energy density, internal pressure and their ratios are calculated from high precision equations of state for eight important fluids including water. To secure conformity to the principle of corresponding states when comparing different fluids, the calculations are carried out along the line defined by equality between the reduced temperature and the reduced pressure of the fluid (Tr = Pr). The results provide additional illustration of the tunability of the solvent properties of water that stands apart from those of other near and supercritical fluids in common use. In addition, an overview is also presented of the derivatives of cohesive energy density, solubility parameter and internal pressure with respect to temperature, pressure and molar volume.
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Agroli, Geri, Atsushi Okamoto, Masaoki Uno, and Noriyoshi Tsuchiya. "Transport and Evolution of Supercritical Fluids During the Formation of the Erdenet Cu–Mo Deposit, Mongolia." Geosciences 10, no. 5 (May 25, 2020): 201. http://dx.doi.org/10.3390/geosciences10050201.
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Petrological and fluid inclusion data were used to characterize multiple generations of veins within the Erdenet Cu–Mo deposit, Mongolia, and constrain the evolution of fluids within the magmatic–hydrothermal system. Three types of veins are present (from early to late): quartz–molybdenite, quartz–pyrite, and quartz. The host rock was emplaced at temperatures of 700–750 °C, the first quartz was precipitated from magma-derived supercritical fluids at 650–700 °C, quartz–molybdenite and quartz–pyrite veins were formed at ~600 °C, and the quartz veins were precipitated in response to retrograde silica solubility caused by decreasing temperatures at <500 °C. We infer that over-pressured fluid beneath the cupola caused localized fluid injection, or that accumulated stress caused ruptures and earthquakes related to sector collapse; these events disrupted impermeable layers and allowed fluids to percolate through weakened zones.