Journal articles: 'Persulfate'

1

Li, Yan, Guansheng Liu, Jinping He, and Hua Zhong. "Activation of Persulfate for Groundwater Remediation: From Bench Studies to Application." Applied Sciences 13, no. 3 (January 18, 2023): 1304. http://dx.doi.org/10.3390/app13031304.

Full text

Abstract:

Persulfate-based in situ chemical oxidation (ISCO) has been increasingly used for the remediation of contaminated groundwater and soil. In recent years, there have been numerous studies in the literature on all aspects of the activation of persulfate for contaminant removal at the laboratory scale, including the ways and mechanisms for the activation, the pathways of contaminant degradation, the factors associated with the activation performance, the methods characterizing the processes, etc. In contrast, studies in the literature on the practical use of the activated persulfate at the field scale are fewer, and at the same time have not been reviewed in an organized way. This review was initiated to summarize on the current research on the applications of activated persulfate for actual site remediation, and to extract the knowledge necessary for the formation of applicable technologies. The remediation efficiency and mechanism of activated persulfates by heat, alkaline, metal-based, and electrokinetic activated technologies are described. The major factors including pH, the persistence of persulfate, and the radius of influence and soil property during ISCO remediation applications were presented and discussed. Finally, the rebound process and impact towards microbial communities after in-situ chemical oxidation on site application were discussed.

APA, Harvard, Vancouver, ISO, and other styles

2

Zhu, Wen, and Jingwei Chen. "Insights into the mechanism of g-C3N4@a-Fe2O3 microsphere heterogeneous activation of hydrogen peroxide under visible light." Advances in Engineering Technology Research 1, no. 2 (September 24, 2022): 443. http://dx.doi.org/10.56028/aetr.1.2.443.

Full text

Abstract:

A-Fe2O3 complex g-C3N4@a-Fe2O3 was successfully prepared by solvothermal method and used in optical Fenton photocatalytic process. Using experimental instruments such as XPS, XRD, DRS, TEM, FTIR, and photochemistry to characterize composite materials. According to the mechanism of the photocatalytic process, combining A-Fe2O3/H2O2 Fenton reagent with g-C3N4 photocatalyst under visible light conditions can effectively accelerate the mineralization of pollutants. The photocatalytic performance of g-C3N4@a-Fe2O3 were evaluated by the decomposition of bisphenol A. When the content of a-Fe2O3 is 15%, the photocatalytic efficiency of the composite is the highest. In addition, cyclic operation, iron leaching concentration, fresh and XRD pattern studies indicate that g-C3N4@a-Fe2O3 composites are very stable and reusable. The results show that the decomposition of BPA by persulfate is a non-free radical reaction, but the coupling a-Fe2O3 with g-C3N4 can effectively activate the formation of persulfate free radicals and reduce BPA under visible light radiation. Studies showed that free radicals generated by electron holes and persulfate formed on catalysts were the main causes of BPA decomposition. Therefore, combined with previous research results, this paper proposed the mechanism of g-C3N4@a-Fe2O3 composite photocatalytic reaction by photo-Fenton. More importantly, this work demonstrates a novel approach to activate persulfates that can efficiently degrade pops and gives some new ideas on the remediation of persulfates in contaminated Water.

APA, Harvard, Vancouver, ISO, and other styles

3

Zhu, Wen, and Jingwei Chen. "Insights into the mechanism of g-C3N4@a-Fe2O3 microsphere heterogeneous activation of hydrogen peroxide under visible light." Advances in Engineering Technology Research 2, no. 1 (September 24, 2022): 443. http://dx.doi.org/10.56028/aetr.2.1.443.

Full text

Abstract:

A-Fe2O3 complex g-C3N4@a-Fe2O3 was successfully prepared by solvothermal method and used in optical Fenton photocatalytic process. Using experimental instruments such as XPS, XRD, DRS, TEM, FTIR, and photochemistry to characterize composite materials. According to the mechanism of the photocatalytic process, combining A-Fe2O3/H2O2 Fenton reagent with g-C3N4 photocatalyst under visible light conditions can effectively accelerate the mineralization of pollutants. The photocatalytic performance of g-C3N4@a-Fe2O3 were evaluated by the decomposition of bisphenol A. When the content of a-Fe2O3 is 15%, the photocatalytic efficiency of the composite is the highest. In addition, cyclic operation, iron leaching concentration, fresh and XRD pattern studies indicate that g-C3N4@a-Fe2O3 composites are very stable and reusable. The results show that the decomposition of BPA by persulfate is a non-free radical reaction, but the coupling a-Fe2O3 with g-C3N4 can effectively activate the formation of persulfate free radicals and reduce BPA under visible light radiation. Studies showed that free radicals generated by electron holes and persulfate formed on catalysts were the main causes of BPA decomposition. Therefore, combined with previous research results, this paper proposed the mechanism of g-C3N4@a-Fe2O3 composite photocatalytic reaction by photo-Fenton. More importantly, this work demonstrates a novel approach to activate persulfates that can efficiently degrade pops and gives some new ideas on the remediation of persulfates in contaminated Water.

APA, Harvard, Vancouver, ISO, and other styles

4

Wu, Bo, Yuanquan Xiong, Jinbo Ru, and Hao Feng. "Removal of NO from flue gas using heat-activated ammonium persulfate aqueous solution in a bubbling reactor." RSC Advances 6, no. 40 (2016): 33919–30. http://dx.doi.org/10.1039/c6ra01524g.

Full text

Abstract:

Ammonium persulfate aqueous solution was used for the first time for NO removal from flue gas in a bubbling bed due to its low cost compared with other persulfate salts (sodium persulfate, potassium persulfate and ammonium persulfate).

APA, Harvard, Vancouver, ISO, and other styles

5

Delegan, Ya A., T. V. Antipova, and M. B. Vainshtein. "Effect of Persulfates on Production of Carotenoids in the Rhodosporidium sphaerocarpum, R. diobovatum and Rhodotorula glutinis Yeast Cultures." Biotekhnologiya 37, no. 3 (2021): 20–28. http://dx.doi.org/10.21519/0234-2758-2021-37-3-20-28.

Full text

Abstract:

The methods for increasing the isolation of carotenoids from yeast producer cultures have been compared. It was shown that the optimal procedure is microwave pretreatment (2450 GHz, 600 W, 40 s) with subsequent extraction of the target products with methanol. Additives of sodium persulfate or ammonium persulfate to aerated culture medium provided additional oxygen sources for the yeast and increased the medium redox potential. The introduction of persulfate led to a 1.3-fold increase in the content of colored carotenoids in the R. dubiovatum VKPM Y-305 biomass as compared to the control without persulfate. In the R. sphaerocarpum VKPM Y-1559 biomass, persulfate at concentrations of 0.15 g/L and 0.50 g/L increased the content of colored carotenoids by 1.3 and 1.4 times, respectively. The optimal persulfate concentent depends on the yeast growth phase and time of exposure to the compound. Higher persulfate concentrations resulted in increased redox potential and discoloration of carotenoids, though without yeast cell death. yeasts, carotenoids, medium redox potential, persulfate

APA, Harvard, Vancouver, ISO, and other styles

6

Anotai, Jin, Nalinrut Masomboon, Chung-Lin Chuang, and Ming-Chun Lu. "Persulfate oxidation for the aniline degradation in aqueous systems." Water Science and Technology 63, no. 7 (April 1, 2011): 1434–40. http://dx.doi.org/10.2166/wst.2011.325.

Full text

Abstract:

Ferrous catalyzed persulfate oxidation of dissolved aniline was investigated in aqueous systems under a variety of ferrous ion concentrations and temperature. Result showed that the addition of ferrous ions accelerated the degradation of aniline by persulfate. For the thermally activated persulfate oxidation experiment, the optimum persulfate/aniline concentration ratio at 30˚C was at 5.4 mM or 20/1. This ratio gave the highest aniline removal of 45%. For the ferrous ion catalyzed persulfate oxidation experiment, there was marginal difference in the result for the various ferrous ion/oxidant molar ratios. Thus, another series of experiment was conducted to determine the optimum ratio and a ferrous ion/persulfate molar ratio of 1.25/1 showed the highest removal efficiency.

APA, Harvard, Vancouver, ISO, and other styles

7

Liu, Jialu, Xijun Gong, Shijun Song, Fengjun Zhang, and Cong Lu. "Heat-Activated Persulfate Oxidation of Chlorinated Solvents in Sandy Soil." Journal of Spectroscopy 2014 (2014): 1–5. http://dx.doi.org/10.1155/2014/578638.

Full text

Abstract:

Heat-activated persulfate oxidative treatment of chlorinated organic solvents containing chlorinated ethenes and ethanes in soil was investigated with different persulfate dosages (20 g/L, 40 g/L, and 60 g/L) and different temperatures (30°C, 40°C, and 50°C). Chlorinated organic solvents removal was increased as persulfate concentration increase. The persulfate dosage of 20 g/L with the highest OE (oxidant efficiency) value was economically suitable for chlorinated organic solvents removal. The increasing temperature contributed to the increasing depletion of chlorinated organic solvents. Chlorinated ethenes were more easily removed than chlorinated ethanes. Moreover, the persulfate depletion followed the pseudo-first-order reaction kinetics (kps=0.0292 [PS]0+0.0008,R2=0.9771). Heat-activated persulfate appeared to be an effective oxidant for treatment of chlorinated hydrocarbons.

APA, Harvard, Vancouver, ISO, and other styles

8

Imran, Muhammad A., Yuzhen Tong, Qing Hu, Mingzhu Liu, and Honghan Chen. "Effects of Persulfate Activation with Pyrite and Zero-Valent Iron for Phthalate Acid Ester Degradation." Water 12, no. 2 (January 28, 2020): 354. http://dx.doi.org/10.3390/w12020354.

Full text

Abstract:

Phthalic acid esters (PAEs) are often detected in remediated groundwater using appropriate oxidant materials by in situ groundwater treatment. The study compares zero-valent iron–persulfate with a pyrite–persulfate system to degrade three PAEs—di(2-ethylhexyl) phthalate (DEHP), dibutyl phthalate (DBP), and dimethyl phthalate (DMP). Column experiments were conducted, and rapid oxidation occurred in a pyrite–persulfate system due to sulfate radical generation. DMP concentration was found at about 60.0% and 53.0% with zero-valent iron (ZVI) and pyrite activation of persulfate, respectively. DBP concentration was measured as 25.0–17.2% and 23.2–16.0% using ZVI–persulfate and pyrite–persulfate systems, respectively. However, DEHP was not detected. The total organic carbon concentration lagged behind the Ʃ3 PAEs. Persulfate consumption with ZVI activation was half of the consumption with pyrite activation. Both systems showed a steady release of iron ions. Overall, the oxidation–reduction potential was higher with pyrite activation. The surface morphologies of ZVI and pyrite were investigated using scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), and XPS. Intensive corrosion occurs on the pyrite surface, whereas the ZVI surface is covered by a netting of iron oxides. The pyrite surface showed more oxidation and less passivation in comparison with ZVI, which results in more availability of Fe 2 + for persulfate activation. The pyrite–persulfate system is relatively preferred for rapid PAE degradation for contamination.

APA, Harvard, Vancouver, ISO, and other styles

9

Fan, Yu Guang, He Wei Hua, Bing Chen, San Ping Zhou, and Hong Xian Lin. "The Influence of Different Stirring Methods on Crystallization Process of Ammonium Persulfate." Advanced Materials Research 634-638 (January 2013): 1672–76. http://dx.doi.org/10.4028/www.scientific.net/amr.634-638.1672.

Full text

Abstract:

Thorough research is performed on crystallization process of ammonium persulfate，the influence of different mixing method on crystallization process of the ammonium persulfate is discussed in this paper, the influence of temperature on crystallization process is also discussed, and then the optimum mixing method for the crystallization of ammonium persulfate is achieved. All these will do great favor to improve the stability of crystallization process of ammonium persulfate .

APA, Harvard, Vancouver, ISO, and other styles

10

Lee, Deokhui, Soyeon Kim, Kai Tang, Michael De Volder, and Yuhoon Hwang. "Oxidative Degradation of Tetracycline by Magnetite and Persulfate: Performance, Water Matrix Effect, and Reaction Mechanism." Nanomaterials 11, no. 9 (September 3, 2021): 2292. http://dx.doi.org/10.3390/nano11092292.

Full text

Abstract:

This study presents a strategy to remove tetracycline by using magnetite-activated persulfate. Magnetite (Fe3O4) was synthesized at high purity levels—as established via X-ray diffractometry, transmission electron microscopy, and N2 sorption analyses—and tetracycline was degraded within 60 min in the presence of both magnetite and persulfate (K2S2O8), while the use of either substance yielded limited degradation efficiency. The effects of magnetite and persulfate dosage, the initial concentration of tetracycline, and the initial pH on the oxidative degradation of tetracycline were interrogated. The results demonstrate that the efficiency of tetracycline removal increased in line with magnetite and persulfate dosage. However, the reaction rate increased only when increasing the magnetite dosage, not the persulfate dosage. This finding indicates that magnetite serves as a catalyst in converting persulfate species into sulfate radicals. Acidic conditions were favorable for tetracycline degradation. Moreover, the effects of using a water matrix were investigated by using wastewater treatment plant effluent. Comparably lower removal efficiencies were obtained in the effluent than in ultrapure water, most likely due to competitive reactions among the organic and inorganic species in the effluent. Increased concentrations of persulfate also enhanced removal efficiency in the effluent. The tetracycline degradation pathway through the magnetite/persulfate system was identified by using a liquid chromatograph-tandem mass spectrometer. Overall, this study demonstrates that heterogeneous Fenton reactions when using a mixture of magnetite and persulfate have a high potential to control micropollutants in wastewater.

APA, Harvard, Vancouver, ISO, and other styles

11

Liu, Jialu, Zhehua Liu, Fengjun Zhang, Xiaosi Su, and Cong Lyu. "Thermally activated persulfate oxidation of NAPL chlorinated organic compounds: effect of soil composition on oxidant demand in different soil-persulfate systems." Water Science and Technology 75, no. 8 (January 27, 2017): 1794–803. http://dx.doi.org/10.2166/wst.2017.052.

Full text

Abstract:

This study investigates the interaction of persulfate with soil components and chlorinated volatile organic compounds (CVOCs), using thermally activated persulfate oxidation in three soil types: high sand content; high clay content; and paddy field soil. The effect of soil composition on the available oxidant demand and CVOC removal rate was evaluated. Results suggest that the treatment efficiency of CVOCs in soil can be ranked as follows: cis-1,2-dichloroethene > trichloroethylene > 1,2-dichloroethane > 1,1,1-trichloroethane. The reactions of soil components with persulfate, shown by the reduction in soil phase natural organics and mineral content, occurred in parallel with persulfate oxidation of CVOCs. Natural oxidant demand from the reaction of soil components with persulfate exerted a large relative contribution to the total oxidant demand. The main influencing factor in oxidant demand in paddy-soil-persulfate systems was natural organics, rather than mineral content as seen with sand and clay soil types exposed to the persulfate system. The competition between CVOCs and soil components for oxidation by persulfate indicates that soil composition exhibits a considerable influence on the available oxidant demand and CVOC removal efficiency. Therefore, soil composition of natural organics and mineral content is a critical factor in estimating the oxidation efficiency of in-situ remediation systems.

APA, Harvard, Vancouver, ISO, and other styles

12

Chen, Chiu Wen, Nguyen Thanh Binh, Yi Kuo Chang, Chang Mao Hung, and Cheng Di Dong. "Remediation of Marine Sediments Contaminated with PAHs Using Sodium Persulfate Activated by Temperature and Nanoscale Zero Valent Iron." Advanced Materials Research 1044-1045 (October 2014): 380–83. http://dx.doi.org/10.4028/www.scientific.net/amr.1044-1045.380.

Full text

Abstract:

The oxidation of 16 polycyclic aromatic hydrocarbons compounds (PAHs) in sediments by sodium persulfate (Na2S2O8) activated by temperature and nanoscale zero−valent iron (nZVI) as the source of catalytic ferrous iron was investigated. The effect of various controlling factors including S2O82− (0.017–170 g/L), nZVI (0.01–1 g/L), and temperature (50–70°C) were performed. The efficiency to remove PAHs was not too high as 10.7–39.1% for unactivated persulfate. Results from experiments indicate that increasing temperature or the addition of nZVI into a persulfate-slurry system could enhance the persulfate oxidation process. The best removal efficiency (86.3%) was attained after 24 hr while adding nZVI (0.5 g/L) to persulfate (170 g/L) at temperature of 25°C. The results of our study suggest that nZVI assisted persulfate oxidation without elevating temperature is a suitable and economic alternative for the ex–situ treatment of PAHs contaminated sediments.

APA, Harvard, Vancouver, ISO, and other styles

13

Astereki, Shokufeh, Bahram Kamarehie, and Ali Jafari. "2-Chlorophenol Removal of Aqueous Solution Using Advanced Oxidation Processes Resulting from Iron/ Persulfate and Ultra Violet/ Persulfate." Iranian Journal of Toxicology 10, no. 3 (July 1, 2016): 1–8. http://dx.doi.org/10.32598/ijt.10.4.219.2.

Full text

Abstract:

Background: Advanced oxidation processes are used to remove toxic aromatic compounds with low biodegradability, such as 2-chlorophenol. This study investigates the use of Sulfate (SO4-) and persulfate (S2O82-) radicals, as one of the advanced oxidation methods, to remove 2- chlorophenol from aquatic solutions. Materials and Methods: This experimental and pilot-scale study was carried out using two chemical batch reactors one of the reactors equipped with UV lamps and the other was on the hot plate. In Iron/ Persulfate (Fe/S2O82- ) and Ultra violet/ Persulfate (UV/S2O82- ) processes different parameters were investigated. Results: The results show that iron, UV, the initial pH of the solution, persulfate concentration have considerable effects on the elimination of 2-chlorophenol in both processes. In both processes, the maximum elimination occurred in acidic conditions. The elimination efficiency increased by increasing the concentration of 2-chlorophenol and UV intensity, and also by decreasing the concentration of persulfate and iron. Accordingly, in Iron/ persulfate and Ultra violet/ persulfate processes 2-chlorophenol was eliminated with 99.96% and 99.58% efficiencies, respectively. Conclusion: Sulfate radicals which are produced from activated persulfate ions with hot-Fe ion and UV radiation have significant impact on the removal of 2-chlorophenol. Therefore, the processes of Fe/S2O82- and UV/S2O82- can be regarded as good choices for industrial wastewater treatment plants operators in the future.

APA, Harvard, Vancouver, ISO, and other styles

14

Liu, Zhentao, Wanpeng Hu, Haiping Zhang, Hui Wang, and Ping Sun. "Enhanced Degradation of Sulfonamide Antibiotics by UV Irradiation Combined with Persulfate." Processes 9, no. 2 (January 26, 2021): 226. http://dx.doi.org/10.3390/pr9020226.

Full text

Abstract:

In this study, the degradation of sulfonamide antibiotics was investigated through persulfate-enhanced UV advanced oxidation process. Factors that may affect the degradation efficiency were analyzed. Results showed that the persulfate imposed a significant enhancement on the UV oxidation process during the sulfathiazole degradation. The combined process of UV/persulfate can effectively remove about 96% of sulfathiazole within 60 min. With the increase in the dosage of persulfate, the removal efficiency increased as well. Different water matrix almost had no effect on the removal efficiency. Two intermediates were found during the sulfathiazole degradation. It can be predicted that the combined process of UV/persulfate has a broad application prospect for removing sulfonamide antibiotics in water treatment.

APA, Harvard, Vancouver, ISO, and other styles

15

Nguyen Thanh, Binh, Nam Vu Van, and Nga Nguyen Thi Bich. "Decomposition efficiency of some azo dyes in the systems consist of persulfate, zero-valent iron powder and UV light in water environment." Vietnam Journal of Catalysis and Adsorption 11, no. 3 (October 16, 2022): 82–87. http://dx.doi.org/10.51316/jca.2022.055.

Full text

Abstract:

This research focused on surveying the decomposition efficiency of methyl orange, alizarin yellow and mordant black -T in the systems without and with UV light in water: alone zero-valent iron; alone persulfate; both zero-valent iron and persulfate. Results of research show that the decomposition efficiency some azo dyes are the highest in the systems of zero-valent iron/persulfate/azo dyes/UV and zero-valent iron/persulfate/azo dyes with the same reaction conditions. After 30 minutes of reaction, the decomposition efficiency of methyl orange, alizarin yellow and mordant black -T are 95.89 %, 90.99 % and 79.85 % in the zero-valent iron/persulfate/azo dyes/UV system and 73.65 %, 71.42 % and 58.94 % in the zero-valent iron/persulfate/azo dyes system. These results can be explained that persulfate has peroxide bond in molecular structure activated by zero-valent iron and UV light to generate in-situ free sulfate radical SO4−• (E0=2.6 V) and free hydroxide radical •OH (E0=2.8 V). These radicals are very active and strong oxidation property. They are agents to oxidize those azo dyes strongly in the water environment.

APA, Harvard, Vancouver, ISO, and other styles

16

Gu, Xiaogang, Shuguang Lu, Xuhong Guo, Jingke Sima, Zhaofu Qiu, and Qian Sui. "Oxidation and reduction performance of 1,1,1-trichloroethane in aqueous solution by means of a combination of persulfate and zero-valent iron." RSC Advances 5, no. 75 (2015): 60849–56. http://dx.doi.org/10.1039/c5ra07655b.

Full text

APA, Harvard, Vancouver, ISO, and other styles

17

Evangelista, Tereza Cristina Santos, and Sabrina Baptista Ferreira. "Sodium Persulfate (Na2S2O8)." SynOpen 05, no. 04 (September 28, 2021): 291–93. http://dx.doi.org/10.1055/a-1656-5714.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Li, Shen Xin, Wei Hu, Ying Wang, Jian Zhang Li, and Cheng Duan Wang. "Study on Phenol Oxidation Catalyzed by Persulfate." Advanced Materials Research 864-867 (December 2013): 96–100. http://dx.doi.org/10.4028/www.scientific.net/amr.864-867.96.

Full text

Abstract:

The phenol oxidation with persulfate catalyzed were studied. Effects of several parameters, such as dose of oxidant, pH, temperature and UV irradiation, were investigated in detail. The results showed that the phenol oxidation by persulfate could be fitted to a pseudo-first order kinetics model. The optimum acidity of the phenol oxidation system in the paper is ca. pH 8.76, the optimum temperature which is ca.70 °C and the optimum molar ratio of persulfate to the phenol is ca.40 in the solution.The results are useful for the treatment of industrial wastewater. Key words: Phenol oxidation Schiff base manganese (III) complexes Persulfate

APA, Harvard, Vancouver, ISO, and other styles

19

Sun, De Dong, Xiao Xu Yan, and Wen Ping Xue. "Oxidative Degradation of Dimethyl Phthalate (DMP) by Persulfate Catalyzed by Ag⁺ Combined with Microwave Irradiation." Advanced Materials Research 610-613 (December 2012): 1209–12. http://dx.doi.org/10.4028/www.scientific.net/amr.610-613.1209.

Full text

Abstract:

The removal of dimethyl phthalate (DMP), which is a pollutant of concern in water environments, was carried out by sodium persulfate (SPS,Na2S2O8) catalyzed by Ag+combined with microwave irradiation. Effects of persulfate concentration, reaction time, microwave(MW) power and catalytic ion Ag+ on the degradation efficiency of DMP by persulfate were examined in batch experiments. The results showed that optimum Na2S2O8 concentration was 0.083mmol/L, and Ag+ concentration was 0.042 mmol/L. Increasing the MW irradiation time , persulfate concentration or Ag+ concentration might significantly accelerate DMP degradation. Catalytic ion Ag+combined with microwave irradiation was an rapid method to activate persulfate, and thus to produce SO4−• which was a powerful oxidant and could degrade DMP effectively. About 80% of DMP and 70% of COD could be degraded in 140s under the conditions of 800W MW power.

APA, Harvard, Vancouver, ISO, and other styles

20

Balaberda, Amy-lynne, and Ania C. Ulrich. "Persulfate Oxidation Coupled with Biodegradation by Pseudomonas fluorescens Enhances Naphthenic Acid Remediation and Toxicity Reduction." Microorganisms 9, no. 7 (July 14, 2021): 1502. http://dx.doi.org/10.3390/microorganisms9071502.

Full text

Abstract:

The extraction of bitumen from the Albertan oilsands produces large amounts of oil sands process-affected water (OSPW) that requires remediation. Classical naphthenic acids (NAs), a complex mixture of organic compounds containing O2− species, are present in the acid extractable organic fraction of OSPW and are a primary cause of acute toxicity. A potential remediation strategy is combining chemical oxidation and biodegradation. Persulfate as an oxidant is advantageous, as it is powerful, economical, and less harmful towards microorganisms. This is the first study to examine persulfate oxidation coupled to biodegradation for NA remediation. Merichem NAs were reacted with 100, 250, 500, and 1000 mg/L of unactivated persulfate at 21 °C and 500 and 1000 mg/L of activated persulfate at 30 °C, then inoculated with Pseudomonas fluorescens LP6a after 2 months. At 21 °C, the coupled treatment removed 52.8–98.9% of Merichem NAs, while 30 °C saw increased removals of 99.4–99.7%. Coupling persulfate oxidation with biodegradation improved removal of Merichem NAs and chemical oxidation demand by up to 1.8× and 6.7×, respectively, and microbial viability was enhanced up to 4.6×. Acute toxicity towards Vibrio fischeri was negatively impacted by synergistic interactions between the persulfate and Merichem NAs; however, it was ultimately reduced by 74.5–100%. This study supports that persulfate oxidation coupled to biodegradation is an effective and feasible treatment to remove NAs and reduce toxicity.

APA, Harvard, Vancouver, ISO, and other styles

21

Li, Junjing, Yiqi Liang, Pengliang Jin, Bin Zhao, Zhaohui Zhang, Xiaojia He, Zilin Tan, Liang Wang, and Xiuwen Cheng. "Heterogeneous Metal-Activated Persulfate and Electrochemically Activated Persulfate: A Review." Catalysts 12, no. 9 (September 9, 2022): 1024. http://dx.doi.org/10.3390/catal12091024.

Full text

Abstract:

The problem of organic pollution in wastewater is an important challenge due to its negative impact on the aquatic environment and human health. This review provides an outline of the research status for a sulfate-based advanced oxidation process in the removal of organic pollutants from water. The progress for metal catalyst activation and electrochemical activation is summarized including the use of catalyst-activated peroxymonosulfate (PMS) and peroxydisulfate (PDS) to generate hydroxyl radicals and sulfate radicals to degrade pollutants in water. This review covers mainly single metal (e.g., cobalt, copper, iron and manganese) and mixed metal catalyst activation as well as electrochemical activation in recent years. The leaching of metal ions in transition metal catalysts, the application of mixed metals, and the combination with the electrochemical process are summarized. The research and development process of the electrochemical activation process for the degradation of the main pollutants is also described in detail.

APA, Harvard, Vancouver, ISO, and other styles

22

Choi, Hyo-yeon, and Daewon Pak. "A Study on Oxidation of Tetramethylammonium Hydroxide (TMAH) using UV/Persulfate." Journal of Korean Society of Environmental Engineers 42, no. 10 (October 31, 2020): 443–51. http://dx.doi.org/10.4491/ksee.2020.42.10.443.

Full text

Abstract:

Objective : In order to efficiently remove TMAH from the wastewater generated by the TFT-LCD manufacturing process, the oxidation of TMAH was tested by applying an UV/persulfate. The optimum reaction conditions for high concentration TMAH oxidation were investigated by evaluating and comparing the removal efficiency according to the factors affecting TMAH oxidative degradation.Methods : In this study, TMAH was decomposed by sulfate radical (SO4-∙) and hydroxyl radical (OH∙) generated from persulfate activated by UV. Factors affecting on the treatment efficiency were try to be optimized by comparing and evaluating the removal efficiency depending on the initial pH, oxidant concentration, and initial TMAH concentration.Results and Discussion : Depending on initial pH (2, 7, 12), persulfate addition (0, 50, 100, 150, 200 mM), initial TMAH concentration (100, 300, 500, 700 mg/L) degradation rates of TMAH were compared. When UV/persulfate was applied, the removal efficiency of TMAH was close to 90% regardless of the initial pH and, at initial pH 12, was the highest with 89%. It was confirmed that the generation pattern of intermediate formed were different depending on the initial pH. When the oxidizing agent was not added, there was little change in TMAH concentration. The removal efficiency was highest when 100 mM persulfate was added. However the efficiency was rather low when 150 mM persulfate was added. When the initial TMAH concentration was 100 mg/L, it was decreased within 150 minutes. As the initial concentration increased, the removal efficiency and reaction rate constant decreased.Conclusions : As a results, during the oxidation of 750 mg/L TMAH by using UV/persulfate, the removal efficiency was highest with initial pH 12 and 100 mM of persulfate addition.

APA, Harvard, Vancouver, ISO, and other styles

23

Ayati, Bita, and Zeinab Ghorbani. "Enhancement of the electro-activated persulfate process in dye removal using graphene oxide nanoparticle." Water Science and Technology 83, no. 9 (April 2, 2021): 2169–82. http://dx.doi.org/10.2166/wst.2021.128.

Full text

Abstract:

Abstract This study aimed to improve the speed of the electrochemical process by graphene oxide nanoparticle as a current accelerator in Acid Blue 25 removal from aqueous solutions. To do so, the effect of different parameters including pH, dye concentration, sodium persulfate concentration, the ratio of sodium persulfate to iron (II) sulfate concentration, current density, and the distance between electrodes was investigated on dye removal. Under optimal conditions of pH = 5, dye concentration = 200 mg/L, sodium persulfate concentration = 500 mg/L, iron (II) sulfate concentration = 100 mg/L, current density = 16.67 mA/cm2, and electrode distance = 2 cm, 95% of dye was removed after 60 min in the electro-activated persulfate process; while the modified electro-activated persulfate process achieved 95% dye removal after only 40 min under the same conditions. This system was able to remove 90% of dye after 60 min at a higher concentration (300 mg/L). Also, the modified electro-activated persulfate process obtained the removal of 80% of COD, and 54% of TOC after 180 min in the mentioned conditions, for the dye concentration of 300 mg/L.

APA, Harvard, Vancouver, ISO, and other styles

24

Sabeti, Zahra, Mahmood Alimohammadi, Samira Yousefzadeh, Hassan Aslani, Maryam Ghani, and Ramin Nabizadeh. "Application of response surface methodology for modeling and optimization of Bacillus subtilis spores inactivation by the UV/persulfate process." Water Supply 17, no. 2 (August 20, 2016): 342–51. http://dx.doi.org/10.2166/ws.2016.139.

Full text

Abstract:

Stronger disinfection techniques are required to inactivate Bacillus subtilis spores as surrogate microorganisms for Cryptosporidium parvum oocysts. In this study, the effects of UV and persulfate separately and also in combination were investigated on B. subtilis spore inactivation. Central composite design and response surface methodology were used to optimize target microorganism reduction. Contact time, initial pH, and persulfate dosage were considered as input experimental variables. Based on the design of the experiments, first and second order response surface models have been developed to correspond to the output response of B. subtilis spore reduction. It can be concluded that microbial reduction by UV alone was more effective than persulfate, while the combined UV/persulfate process demonstrated the highest log reduction (4.1) under the following optimal conditions: 60 min contact time, pH = 7.8, and persulfate dosage of 30 mM. On the other hand, the optimal condition for UV treatment was a contact time of 60 min at a pH of 5.0, which led to a 3.19 log spore inactivation. Consequently, the UV/persulfate system can be introduced as an alternative disinfectant for the inactivation of B. subtilis spores.

APA, Harvard, Vancouver, ISO, and other styles

25

Rahman, Mahbubor, Tuba DEMIREL, and Ismail KARACAN. "KARBON LİF ÜRETİMİNDE POLİAKRİLONİTRİL ELYAFLARIN TERMAL OKSİDASYONU." Euroasia Journal of Mathematics, Engineering, Natural & Medical Sciences 8, no. 17 (September 25, 2021): 160–70. http://dx.doi.org/10.38065/euroasiaorg.674.

Full text

Abstract:

Thermal oxidation of polyacrylonitrile (PAN) fibers was accomplished at temperatures up to 250°C for different oxidation times. Chemical integration of PAN fibers with an aqueous solution of ammonium persulfate was performed before starting thermal oxidation. The results recommend that ammonium persulfate integration enhanced the oxidation reactions of the PAN fibers and resulting in enhanced thermal stability. Ammonium persulfate impregnation followed by the oxidation process in the air environment leads to significant deviations in the characteristics of PAN fibers. To perform structural characterization of the raw and ammonium persulfate (APS) incorporated and stabilized samples, XRD, IR-spectroscopy, TGA was executed in this study. Investigation of the XRD and infrared spectroscopy outcomes recommended quick aromatization reactions with growing oxidation periods. The TGA traces indicated a comparative enhancement in the thermal stability of the PAN fibers by the increased carbon yield with the rise of the oxidation time. The overall findings recommend that ammonium persulfate incorporation was very influential in stimulating the oxidation process.

APA, Harvard, Vancouver, ISO, and other styles

26

Rozenberga, Linda, Laura Vikele, Linda Vecbiskena, Inese Sable, Marianna Laka, and Uldis Grinfelds. "Preparation of Nanocellulose Using Ammonium Persulfate and Method’s Comparison with other Techniques." Key Engineering Materials 674 (January 2016): 21–25. http://dx.doi.org/10.4028/www.scientific.net/kem.674.21.

Full text

Abstract:

Cellulose nanocrystals (CNCs) have generated increasing attention in the past few years as potential sources of innovative bionanomaterials. This study focuses on an alternative method of nanocellulose particle preparation, using ammonium persulfate, and compares this to existing techniques. Nanoparticles were prepared using 4 different methods: thermocatalytic method, TEMPO oxidation, the acid hydrolysis and oxidation with ammonium persulfate. With the ammonium persulfate method, the grinding time of the oxidised cellulose is reduced drastically to only 0.5h, and results in an average nanoparticles size of 404.5 nm, zeta potential of -26.4 and crystallinity degree of 80%. Based on comparison of these parameters to results from existing techniques, oxidising cellulose using ammonium persulfate appears to be a promising alternative.

APA, Harvard, Vancouver, ISO, and other styles

27

Deng, Changbang, Liang Jiang, and Linmao Qian. "Synergistic Effect of F⁻ and Persulfate in Efficient Titanium Alloy Chemical Mechanical Polishing." ECS Journal of Solid State Science and Technology 10, no. 11 (November 1, 2021): 114003. http://dx.doi.org/10.1149/2162-8777/ac305a.

Full text

Abstract:

Titanium alloys require excellent surface quality to achieve superior performance in biomedicine. In this paper, chemical mechanical polishing (CMP) was employed to prepare a satisfactory TC4 alloy surface. F− and persulfate were used as critical additives to improve the CMP efficiency. In comparison with the basic slurry without F− and persulfate, the slurry containing only F−, and the slurry containing only persulfate, the slurries containing both F− and persulfate lead to a noticeable increase in the material removal rate (MRR), which is attributed to the synergistic effect of F− and persulfate. After adding 80 mM NaF and 100 mM (NH4)2S2O8 to the basic slurry, the MRR increases significantly from 11 nm min−1 to 203 nm min−1, and the surface roughness R a reaches 3.4 nm. Moreover, there is no processing damage in the substrate. For the synergistic effect, Ti in TC4 alloy is first oxidized to Ti3+ and Ti4+ oxides by persulfate, and then HF, F− and HF2 − attack the oxides to produce soluble complex compounds, promoting the corrosion and the resultant MRR. This study provides a feasible way to achieve the high-efficiency CMP of titanium alloys via the synergistic effect of complexing agent and oxidizer to enhance the corrosive wear.

APA, Harvard, Vancouver, ISO, and other styles

28

Gu, Zhen Yu, Zhong Zhong, Zhi Qiu, Fu Cheng Sun, and Zong Lin Zhang. "Potential for Persulfate Degradation of Semi Volatile Organic Compounds Contamination." Advanced Materials Research 651 (January 2013): 109–14. http://dx.doi.org/10.4028/www.scientific.net/amr.651.109.

Full text

Abstract:

Semi Volatile Organic Compounds (SVOCs) are common contaminants found in brownfield sites that used to be agrochemical plants, chemical storage sites, and industrial areas. Chemical oxidation showed great potential to provide a rapid, cost-effective approach for SVOCs contaminate sites. Chemical oxidation using persulfate was demonstrated by degrading both lab samples and on-site samples from a local o-ansidine contaminated site in this study. The soil samples were mixed with persulfate at different ratios, while adding supplements for the purpose of persulfate thermal activation and pH control. Experiments for optimal usage and treatment duration were also investigated to provide guidance for following demonstration project. Soil samples were analyzed before and after the treatments to compare the o-ansidine concentration changes. The results suggested an optimal ratio of persulfate at 0.5% (in w/w) for this study, with 90% or more removal of most samples in 3 days, at an average cost of oxidants per ton of soil around 800 RMB. This study demonstrated the potential of persulfate oxidation as a novel and reliable approach for o-ansidine contaminated soil, as well as the possibility of extending the remediation concept for other organic contamination scenarios. In addition, persulfate oxidation could also be combined with other remediation technology in future due to its simplicity and convenience.

APA, Harvard, Vancouver, ISO, and other styles

29

Chen, Ku-Fan, Yu-Chen Chang, and Kuan-Yu Liu. "A kinetic and mechanistic study of the degradation of 1,2-dichloroethane and methyl tert-butyl ether using alkaline-activated persulfate oxidation." RSC Advances 6, no. 79 (2016): 75578–87. http://dx.doi.org/10.1039/c6ra16050f.

Full text

Abstract:

Alkaline-activated persulfate accelerates the degradation of 1,2-dichloroethane (1,2-DCA) while the rate of degradation of methyl tert-butyl ether (MTBE) in alkaline-activated persulfate system is decreased.

APA, Harvard, Vancouver, ISO, and other styles

30

Le, Chen, Jin-Hua Wu, Ping Li, Xiangde Wang, Neng-Wu Zhu, Ping-Xiao Wu, and Bo Yang. "Decolorization of anthraquinone dye Reactive Blue 19 by the combination of persulfate and zero-valent iron." Water Science and Technology 64, no. 3 (August 1, 2011): 754–59. http://dx.doi.org/10.2166/wst.2011.708.

Full text

Abstract:

Decolorization of anthraquinone dye Reactive Blue 19 (RB19) with sulfate radicals generated in situ from persulfate and zero-valent iron (ZVI) was investigated. The effects of initial solution pH, initial concentration of RB19, ZVI and persulfate, reaction temperature and common dissolved anions were studied. 100% color removal efficiency and 54% TOC removal efficiency were achieved in 45 min with an initial RB19 concentration of 0.1 mM under typical conditions (pH 7.0, 0.8 g L−1 ZVI, 10 mM persulfate and 30 °C). The decolorization efficiency of RB19 increased with higher iron dosage, higher initial persulfate concentration, and higher reaction temperature. It is also an acid driven process. The decolorization process followed pseudo-first order kinetics and the activation energy was 98.1 kJ mol−1. RB19 decolorization was inhibited by common dissolved anions such as Cl−, NO3−, H2PO4− and HCO3− since they reacted with sulfate radicals that retarded the oxidation process. The experiment demonstrated that the combination of persulfate and ZVI was a promising technology for the decolorization of dye wastewater.

APA, Harvard, Vancouver, ISO, and other styles

31

Iribagiza, Marie Rose, Ting Li, Wenjing Liang, Yuanyuan Wu, and Fang Zhu. "Enhanced Mechanism of Nano Zero-Valent Iron Activated Persulfate for Persistent Organic Pollutants in the Environment." Global Environmental Engineers 9 (March 14, 2022): 1–11. http://dx.doi.org/10.15377/2410-3624.2022.09.1.

Full text

Abstract:

The advanced oxidation process based on persulfate has a broad application prospect in the remediation of organic pollutants. As an effective, low-cost and environmentally friendly material, nano-zero-valent iron (nZVI) can effectively activate persulfate (nZVI/PS) to generate strongly oxidizing sulfate radical for removing organic pollutants in the environment. In this review, we first clarify the activation pathway of nZVI activated persulfate including direct activation and indirect activation. Direct activation means that the electrons released by nZVI directly participate in the activation of PS; indirect activation means that Fe0 corrodes to generate Fe2+, and Fe2+ further activate the persulfate. Then, the mechanism of nZVI/PS system to degrade organic pollutants including electron transfer, hydrogen extraction and addition reactions are also discussed. Finally, combined with the activation pathway and the mechanism of degrading organic pollutants, we propose several prospects for the future research direction of nZVI activated persulfate. As a result, this review provides a theoretical basis for the nZVI/PS advanced oxidation system to remediate actual sites contaminated with organic pollutants.

APA, Harvard, Vancouver, ISO, and other styles

32

Norzaee, Samira, Edris Bazrafshan, Babak Djahed, Ferdos Kord Mostafapour, and Razieh Khaksefidi. "UV Activation of Persulfate for Removal of Penicillin G Antibiotics in Aqueous Solution." Scientific World Journal 2017 (2017): 1–6. http://dx.doi.org/10.1155/2017/3519487.

Full text

Abstract:

Penicillin G (PG) is one of the most widely consumed antibiotics around the world. Release of PG in environment may lead to contamination of water resources. The aim of the present work is to assess feasibility of applying UV-activated persulfate process in removal of PG from aquatic environments. The study examined the effect of pH (3–11), persulfate initial concentration (0.5–3 mM), reaction time (15–90 minutes), and initial concentration of PG (0.02–0.14 mM) on PG decomposition. Also, the pseudo-first-order kinetic model was used for kinetic analysis of PG removal. The results indicated that UV-activated persulfate process can effectively eliminate PG from water. The highest PG removal efficiency was obtained as 94.28% at pH 5, and the decomposition percentage was raised by increasing persulfate dose from 0.5 to 3 mM and the reaction time from 15 to 90 minutes. Besides, the removal efficiency decreased through increasing the initial concentration of PG. UV-activated persulfate process effectively decomposes PG and eliminates it from water.

APA, Harvard, Vancouver, ISO, and other styles

33

Ahmed, Sameh Abdelfattah Araby, and Elena S. Gogina. "Phenol removal by enhanced electrocoagulation process with persulfate salt." Vestnik MGSU, no. 12 (December 2021): 1592–98. http://dx.doi.org/10.22227/1997-0935.2021.12.1592-1598.

Full text

Abstract:

Introduction. Phenol is classified as priority pollutant. Phenol and its derivatives are stable in water, environmental contamination, and health concerns that are used as raw material in many chemical industries. This study investigated the removal of phenol by the reactivity of free sulfate radicals (SO4•–), activated by electrochemically generated Fe2+/Fe3+ ions which furthermore are evaluated to destroy phenol in aqueous solution. Materials and methods. In the present experimental study, electrocoagulation reactor by iron electrodes is used in the presence of persulfate ions to phenol removing from aqueous solutions. In this regard, the effect of four independent variables including pH, electric current, persulfate dosage, and initial phenol concentration were studied on phenol removal. Results. The study determined the optimum conditions for maximum phenol removal using electro-persulfate process (EPS) as pH 3, 7.4 mM persulfate dosage, 27.78 mA/cm2 current density, and 100 mg/L initial phenol concentration at 30-min reaction time. The results showed that the efficiency of phenol removal was directly related to the initial persulfate dosage. In addition, the pH values, less than the phenol pKa, has slight effect onto the phenol removal. However, it was inversely correlated with a highly alkaline pH and higher phenol concentration. Conclusions. The study concluded that electro-persulfate process is an effective and robust process that can be used for handling of phenol containing wastewater.

APA, Harvard, Vancouver, ISO, and other styles

34

Ma, Xiao, and Zhenjun Wang. "Removal of Ciprofloxacin from Wastewater by Ultrasound/Electric Field/Sodium Persulfate (US/E/PS)." Processes 10, no. 1 (January 7, 2022): 124. http://dx.doi.org/10.3390/pr10010124.

Full text

Abstract:

Ciprofloxacin (CIP), as a common antibiotic used in human clinical and livestock farming, is discharged into natural water bodies and its concentration has increased in the last years. Its stable chemical structure is difficult to remove by conventional techniques. Residual ciprofloxacin in the environment has become an emerging micropollutant that promotes the generation of resistance genes of bacteria and endangers ecosystem balance and human health. Removal of ciprofloxacin from water by the system of ultrasound/electric field/sodium persulfate (US/E/PS) was investigated. Firstly, CIP degradation affects by different oxidation methods, such as ultrasonic oxidation, electro-oxidation, and persulfate oxidation, and their four combined oxidation methods (ultrasound-activated persulfate oxidation, electro-activated persulfate oxidation, ultrasound-enhanced electro-oxidation, and ultrasound-enhanced electro-activated persulfate oxidation), on the target contaminants were compared. Secondly, the influences of parameters on the CIP degradation by an ultrasound-enhanced electro-activation-persulfate reaction system were investigated. Thirdly, the possible free radical species in the ultrasound-enhanced electro-activation-sulfate reaction system were identified and the dominant free radical species in the system were analyzed. Finally, the samples of CIP in the US/E/PS system were tested by liquid mass spectrometry, and the possible intermediate products and degradation path were speculated. The results indicate that the US/E/PS system is of great potential application value in the removal of organic pollution and environmental purification.

APA, Harvard, Vancouver, ISO, and other styles

35

Liu, Yueheng. "Study on UV Ferrous Activated Persulfate Degradation Conditions of Thiacloprid Pesticide Residues in Environmental Water." BIO Web of Conferences 55 (2022): 01004. http://dx.doi.org/10.1051/bioconf/20225501004.

Full text

Abstract:

In order to degrade thiacloprid pesticide residues in environmental water, a UV ferrous activated persulfate system was constructed. The effects of Fe2+ concentration, persulfate concentration, pH value and UV power on the degradation rate of thiacloprid were investigated through a single factor experiment. On this basis, a mathematical model between the influencing factors and the response value was established using response surface experiment. The model fitting results showed that predicted highest thiacloprid degradation rate of the model was 100% when the Fe2+ concentration was 0.340mmol/L, the persulfate concentration was 0.610mmol/L and the UV power was 45.81W. The validation test result (99.2%) was basically consistent with the predicted value, indicating that the response surface methodology was feasible for optimizing the degradation of thiacloprid in the UV ferrous activated persulfate system.

APA, Harvard, Vancouver, ISO, and other styles

36

Khashij, Maryam, Mohammad Mehralian, and Zahra Goodarzvand Chegini. "Degradation of acetaminophen (ACT) by ozone/persulfate oxidation process: experimental and degradation pathways." Pigment & Resin Technology 49, no. 5 (April 13, 2020): 363–68. http://dx.doi.org/10.1108/prt-11-2019-0107.

Full text

Abstract:

Purpose The purpose of this study to investigate acetaminophen (ACT) degradation efficiencies by using ozone/persulfate oxidation process in a batch reactor. In addition, the effects of various parameters on the ACT removal efficiency toward pathway inference of ACT degradation were investigated. Design/methodology/approach The experiments were in the 2 L glass vessels. Ozone gas with flow rate at 70 L.h−1 was produced by ozone generator. After the adjustment of the pH, various dosages of persulfate (1, 3, 5, 7 and 9 mmol.L−1) were then added to the 500 mL ACT-containing solution with 150 mg.L−1 of concentration. Afterward, ozone gas was diffused in glass vessels. The solution after reaction flowed into the storage tank for the detection. The investigated parameters included pH and the amount of ozone and persulfate addition. For comparison of the ACT degradation efficiency, ozone/persulfate, ozone and persulfate oxidation in reactor was carried out. The ACT concentration using a HPLC system equipped with 2998 PDA detector was determined at an absorbance of 242 nm. Findings ACT degradation percentage by using ozone or persulfate in the process were at 63.7% and 22.3%, respectively, whereas O3/persulfate oxidation process achieved degradation percentage at 91.4% in 30 min. Degradation efficiency of ACT was affected by different parameter like pH and addition of ozone or persulfate, and highest degradation obtained when pH and concentrations of persulfate and ozone was 10 and 3 mmol.L−1 and 60 mg.L−1, respectively. O3, OH• and SO4− were evidenced to be the radicals for degradation of ACT through direct and indirect oxidation. Gas chromatography–mass spectrometer analysis showed intermediates including N-(3,4-dihydroxyphenyl) formamide, hydroquinone, benzoic acid, 4-methylbenzene-1,2-diol, 4-aminophenol. Practical implications This study provided a simple and effective way for degradation of activated ACT as emerging contaminants from aqueous solution. This way was conducted to protect environment from one of the most important and abundant pharmaceutical and personal care product in aquatic environments. Originality/value There are two main innovations. One is that the novel process is performed successfully for pharmaceutical degradation. The other is that the optimized conditions are obtained. In addition, the effects of various parameters on the ACT removal efficiency toward pathway inference of ACT degradation were investigated.

APA, Harvard, Vancouver, ISO, and other styles

37

Li, Shen Xin, Wei Hu, and Cheng Duan Wang. "Decolourization of Alizarin Red by Persulfate." Advanced Materials Research 610-613 (December 2012): 300–305. http://dx.doi.org/10.4028/www.scientific.net/amr.610-613.300.

Full text

Abstract:

The decolourization of dye wastewater by persulfate was studied using alizarin red as a model dye wastewater. Effects of several parameters, such as dose of oxidant, ionic strength, pH, temperature and UV irradiation, were investigated in detail. The results showed that the decolourization reaction of alizarin red by persulfate could be fitted to a pseudo-first order kinetics model. In addition, no degradation products were observed during the decolourization of alizarin red by persulfate. The results are useful for the treatment of dye wastewater.

APA, Harvard, Vancouver, ISO, and other styles

38

Penkin, Anton Anatol'yevich. "RECYCLING OF WET-STRENGTH TISSUE PAPER. PART 1. KINETICS OF PAPER DISINTEGRATION AT REPULP-ING PROCESS." chemistry of plant raw material, no. 1 (March 10, 2022): 355–65. http://dx.doi.org/10.14258/jcprm.2022019893.

Full text

Abstract:

The present investigation focuses on disintegration kinetics of wet-strength tissue paper in various termo-alkaline and chemical conditions of batch low-consistency repulping process. As chlorine-free repulping aids, we applied sodium persulfate in its original state and in combination with peroxy activator (chemically activated form of sodium persulfate). Based on a first-order kinetic model, we estimated the influence of repulping conditions on the intensity of wet-strength paper defiberization process by the disintegration rate constant kd. The values of kd were found by linear least-squares curve fitting of the experimental data in the t, ln (F'/100) coordinate system, where F' is non-disintegrated or non-defibrated portion of paper, t – repulping time. The results have shown that the termo-alkaline repulping of wet-strength tissue paper (T=60 °C, pH=10.5) compared with mild conditions of repulping (T=40 °C, pH=8.5) leads to an increase of the rate constant of disintegration kd from 5.6·10-3 min-1 to 9.7·10-3 min-1. Addition of 2% persulfate at termo-alkaline repulping increases the rate constant of disintegration kd up to 14,0·10-3 min-1. Application of chemically activated persulfate under the same conditions allows to further increase the kd up to 23.4·10-3 min-1. Raising the temperature and pH of the pulp during persulfate repulping increases the disintegration rate constant kd nonlinearly. Finally, addition of persulfate along with thermo-alkaline pulp treatment lead to decline repulping time and energy by 31% and 29%. It should be noted, that more significant savings of time and energy (57% and 59% respectively) we found at the application of persulfate in a chemically activated form.

APA, Harvard, Vancouver, ISO, and other styles

39

Penkin, Anton Anatol'yevich. "RECYCLING OF WET-STRENGTH TISSUE PAPER. PART 1. KINETICS OF PAPER DISINTEGRATION AT REPULP-ING PROCESS." chemistry of plant raw material, no. 1 (March 10, 2022): 355–65. http://dx.doi.org/10.14258/jcprm.2022019893.

Full text

Abstract:

The present investigation focuses on disintegration kinetics of wet-strength tissue paper in various termo-alkaline and chemical conditions of batch low-consistency repulping process. As chlorine-free repulping aids, we applied sodium persulfate in its original state and in combination with peroxy activator (chemically activated form of sodium persulfate). Based on a first-order kinetic model, we estimated the influence of repulping conditions on the intensity of wet-strength paper defiberization process by the disintegration rate constant kd. The values of kd were found by linear least-squares curve fitting of the experimental data in the t, ln (F'/100) coordinate system, where F' is non-disintegrated or non-defibrated portion of paper, t – repulping time. The results have shown that the termo-alkaline repulping of wet-strength tissue paper (T=60 °C, pH=10.5) compared with mild conditions of repulping (T=40 °C, pH=8.5) leads to an increase of the rate constant of disintegration kd from 5.6·10-3 min-1 to 9.7·10-3 min-1. Addition of 2% persulfate at termo-alkaline repulping increases the rate constant of disintegration kd up to 14,0·10-3 min-1. Application of chemically activated persulfate under the same conditions allows to further increase the kd up to 23.4·10-3 min-1. Raising the temperature and pH of the pulp during persulfate repulping increases the disintegration rate constant kd nonlinearly. Finally, addition of persulfate along with thermo-alkaline pulp treatment lead to decline repulping time and energy by 31% and 29%. It should be noted, that more significant savings of time and energy (57% and 59% respectively) we found at the application of persulfate in a chemically activated form.

APA, Harvard, Vancouver, ISO, and other styles

40

Sun, Jie, Guotong Xia, Wenjin Yang, Yue Hu, and Weibo Shen. "Microwave-assisted method to degrade phenol using persulfate or hydrogen peroxide catalyzed by Cu-bearing silicon carbide." Water Science and Technology 82, no. 4 (August 6, 2020): 704–14. http://dx.doi.org/10.2166/wst.2020.370.

Full text

Abstract:

Abstract The radical generation properties of hydrogen peroxide and persulfate for phenol degradation were investigated under microwave irradiation using copper-doped silicon carbide (Cu/SiC) composites as catalyst. The results showed that 90% and 70% of phenol and total organic carbon (TOC), respectively, were removed within 7 min. Microwave activation of hydrogen peroxide and sodium persulfate in terms of thermal effects and accelerated electron transfer was analyzed by degradation kinetics and X-ray photoelectron spectroscopy (XPS). The microwave activation of Na2S2O8 demonstrated that the hot spots promote decomposition of persulfate more rapidly and the rate of persulfate decomposition was more than three times the activation rate of a normal heating method. There is a synergistic effect between Cu and microwave radiation, which is highlighted by the H2O2 activation; ·OH was generated due to the redox cycle between Cu(I)/Cu(II) and was responsible for phenol degradation using H2O2. High performance liquid chromatography (HPLC) analysis indicated that hydroxylation and sulfate radicals addition of phenol were the initial oxidation reaction steps of hydrogen peroxide and persulfate, respectively, followed by further oxidation to form short-chain carboxylic acids.

APA, Harvard, Vancouver, ISO, and other styles

41

Tang, Chenliu, Zhicheng Long, Yidan Wang, Dongze Ma, and Xiaobiao Zhu. "Sulfate Decelerated Ferrous Ion-Activated Persulfate Oxidation of Azo Dye Reactive Brilliant Red: Influence Factors, Mechanisms, and Control Methods." Catalysts 12, no. 10 (October 10, 2022): 1207. http://dx.doi.org/10.3390/catal12101207.

Full text

Abstract:

This study investigated the inhibition effects of sulfate on ferrous ion-activated persulfate oxidation of azo dye reactive brilliant red X-3B. The experimental results showed that the degradation efficiency of reactive brilliant red X-3B decreased from 100% to 63% in 60 min when the initial concentration of sulfate increased from 0 to 3 g/L. The ferrous/persulfate molar ratio had remarkable influence on persulfate oxidation capability in presence of sulfate. SO42− could coordinate with Fe2+ and Fe3+ in generating FeSO4 ion pairs as well as FeSO4+ or Fe(SO4)2− complexes, which were difficult to activate persulfate and reduced the regeneration of Fe2+. Radicals quenching and electron paramagnetic resonance experiments showed that ·OH and SO4·− were responsible for the oxidation of reactive brilliant red X-3B; however, the addition of sulfate significantly inhibited the generation of SO4·−, and then the generation of ·OH. Moreover, the corresponding Nernst equation indicated that high concentration of sulfate reduced the oxidation potential of SO4·−/SO42−. Experimental results proved that the adverse effects of sulfate on the persulfate oxidation could be counteracted either by batch addition of ferrous or by adding Ba2+ to remove SO42− in the system.

APA, Harvard, Vancouver, ISO, and other styles

42

Zhou, Peng, Jing Zhang, Jilong Liu, Yongli Zhang, Juan Liang, Ya Liu, Bei Liu, and Wei Zhang. "Degradation of organic contaminants by activated persulfate using zero valent copper in acidic aqueous conditions." RSC Advances 6, no. 101 (2016): 99532–39. http://dx.doi.org/10.1039/c6ra24431a.

Full text

Abstract:

Persulfate can accelerate the corrosion of nZVC to release Cu⁺ in the acidic aqueous condition, and the reactive radicals were generated through the further activation of persulfate by intermediate Cu⁺via a Fenton-like reaction.

APA, Harvard, Vancouver, ISO, and other styles

43

Miao, Dongtian, Guoshuai Liu, Qiuping Wei, Naixiu Hu, Kuangzhi Zheng, Chengwu Zhu, Ting Liu, Kechao Zhou, Zhiming Yu, and Li Ma. "Electro-activated persulfate oxidation of malachite green by boron-doped diamond (BDD) anode: effect of degradation process parameters." Water Science and Technology 81, no. 5 (March 1, 2020): 925–35. http://dx.doi.org/10.2166/wst.2020.176.

Full text

Abstract:

Abstract In this paper, boron-doped diamond (BDD) electro-activated persulfate was studied to decompose malachite green (MG). The degradation results indicate that the decolorization performance of MG for the BDD electro-activated persulfate (BDD-EAP) system is 3.37 times that of BDD electrochemical oxidation (BDD-EO) system, and BDD-EAP system also exhibited an enhanced total organic content (TOC) removal (2.2 times) compared with BDD-EO system. Besides, the degradation parameters such as persulfate concentration, current density, and pH were studied in detail. In a wider range of pH (2–10), the MG can be efficiently removed (>95%) in 0.02 M persulfate solution with a low current density of 1.7 mA/cm2 after 30 min. The BDD-EAP technology decomposes organic compounds without the diffusion limitation and avoids pH adjustment, which makes the EO treatment of organic wastewater more efficient and more economical.

APA, Harvard, Vancouver, ISO, and other styles

44

Tian, Ke, Fengyin Shi, Menghan Cao, Qingzhu Zheng, and Guangshan Zhang. "A Review of Persulfate Activation by Magnetic Catalysts to Degrade Organic Contaminants: Mechanisms and Applications." Catalysts 12, no. 9 (September 16, 2022): 1058. http://dx.doi.org/10.3390/catal12091058.

Full text

Abstract:

All kinds of refractory organic pollutants in environmental water pose a serious threat to human health and ecosystems. In recent decades, sulfate radical-based advanced oxidation processes (SR-AOPs) have attracted extensive attention in the removal of these organic pollutants due to their high redox potential and unique selectivity. This review first introduces persulfate activation by magnetic catalysts to degrade organic contaminants. We present the advances and classifications in the generation of sulfate radicals using magnetic catalysts. Subsequently, the degradation mechanisms in magnetic catalysts activated persulfate system are summarized and discussed. After an integrated presentation of magnetic catalysts in SR-AOPs, we discuss the application of persulfate activation by magnetic catalysts in the treatment of wastewater, landfill leachate, biological waste sludge, and soil containing organic pollutants. Finally, the current challenges and perspectives of magnetic catalysts that activated persulfate systems are summarized and put forward.

APA, Harvard, Vancouver, ISO, and other styles

45

Ma, Yan, Zhenhai Liu, Yanqiu Xu, Shengkun Zhou, Yi Wu, Jin Wang, Zhanbin Huang, and Yi Shi. "Remediating Potentially Toxic Metal and Organic Co-Contamination of Soil by Combining In Situ Solidification/Stabilization and Chemical Oxidation: Efficacy, Mechanism, and Evaluation." International Journal of Environmental Research and Public Health 15, no. 11 (November 20, 2018): 2595. http://dx.doi.org/10.3390/ijerph15112595.

Full text

Abstract:

Most soil remediation studies investigated single contaminants or multiple contaminants of the same type. However, in field conditions, soils are often contaminated with potentially both toxic metals and organic pollutants, posing a serious technical challenge. Here, batch experiments were conducted to evaluate the performance of combining in situ solidification/stabilization (ISS) and in situ chemical oxidation (ISCO) for the simultaneous removal of aniline (1000 mg/kg) and Cd (10 mg/kg). All four tested ISS amendments, especially quick lime and Portland cement, promoted in situ chemical oxidation with activated persulfate in contaminated soil. Combined ISS/ISCO remediation effectively removed aniline and reduced the bioavailable Cd content at optimal initial persulfate and ISS amendment concentrations of 1.08 mol/kg and 30 wt% with a seven-day curing time, and significantly reduced leaching. Persulfate inhibited the reduction of the bioavailable Cd content, and ISS amendment with persulfate did not synergistically remediate Cd in co-contaminated soil. Strong alkalinity and high temperature were the main mechanisms driving rapid pollutant removal and immobilization. The reaction of CaO with water released heat, and Ca(OH)2 formation increased the pH. The relative contributions of heat vs. alkaline activation, as well as the contaminant removal efficiency, increased with ISS amendment CaO content. Combined treatment altered the soil physicochemical properties, and significantly increased Ca and S contents. Activated persulfate-related reactions did not negatively impact unconfined compressive strength and hydraulic conductivity. This work improves the selection of persulfate activation methods for the treatment of soils co-contaminated with both potentially toxic metals and organic pollutants.

APA, Harvard, Vancouver, ISO, and other styles

46

Yang, Bo Ming, Chih Ming Kao, Chiu Wen Chen, Wen Pei Sung, and Rao Y. Surampalli. "Application of In Situ Chemical Oxidation for the Remediation of TPH-Contaminated Soils." Applied Mechanics and Materials 121-126 (October 2011): 196–200. http://dx.doi.org/10.4028/www.scientific.net/amm.121-126.196.

Full text

Abstract:

Soils at many existing and former industrial areas and disposal sites are contaminated by petroleum hydrocarbons. In this study, laboratory bench-scale experiments were performed to evaluate the effectiveness of applying in situ chemical oxidation (ISCO) on the treatment of petroleum-hydrocarbon contaminated soils. Three different oxidation processes including Fenton’s oxidation, persulfate oxidation, and permanganate oxidation were evaluated with initial total petroleum hydrocarbon (TPH) concentration of approximately 3,920 mg/kg. The major control factors were oxidant species (hydrogen peroxide, persulfate, permanganate) and soil to liquid volume ratios (1 to 3). The oxidant concentration was 5 wt.%. Ferrous iron was used as the catalyst during the Fenton’s oxidation and persulfate oxidation processes, and the oxidant to ferrous iron molar ratio was 1 to 0.1. Among these three oxidation processes, contaminated soils treated by permanganate oxidation had the highest TPH removal efficiency (94% of TPH removal) during 360 min of operation. Approximately 75 and 61% of TPH removal was observed in batch experiments applying Fenton’s oxidation and persulfate oxidation, respectively. Due to the consumption of ferrous iron (used as the catalytic chemical) in the early stage during the operational period, both persulfate and Fenton’s oxidation processes had less TPH removal efficiencies. Frequent supplement of catalyst is required when persulfate and Fenton’s oxidation is applied for field application. Results from this study indicate that the ISCO scheme is a feasible technology for the treatment of petroleum-hydrocarbon contaminated soils within a short treatment period. The experimental results can be used for a scale-up system for practical application.

APA, Harvard, Vancouver, ISO, and other styles

47

Zhao, Zhen Qiang, and Xin Ping Ouyang. "Effect of Oxidation on the Structures and Properties of Lignin." Advanced Materials Research 550-553 (July 2012): 1208–13. http://dx.doi.org/10.4028/www.scientific.net/amr.550-553.1208.

Full text

Abstract:

The effect of three kinds of oxidants, hydrogen peroxide, copper oxide and ammonium persulfate, on the structures and properties of modified lignin were investigated. It is found out that a low dosage of oxidant can result in the increase in the content of active phenolic hydroxyl and carboxyl. It is most likely to cleave β-O-4 and C-C bond in lignin molecule. Compared to ammonium persulfate and copper oxide, hydrogen peroxide exhibits relatively mild oxidation to lignin. The oxidation of lignin with excessive ammonium persulfate and hydrogen peroxide can cause free radical polymerization of alkali lignin, leading to the increase of molecular weight and the decrease of the sulfonation degree of the sulfonated lignin followed by oxidation and hydroxymethylation (OSAL). Ammonium persulfate exhibits a stronger capacity to initiate free polymerization reaction compared to hydrogen peroxide, so it is suitable to use a low dosage of ammonium persulfate for the oxidation of alkali lignin. Copper oxide could not cause a free radical polymerization, therefore the molecular weight of the sulfonated lignin is lower, and the sulfonation degree is higher. OSAL with a good dispersive effect to cement paste should simultaneously possess a high sulfonation degree and an appropriate molecular weight.

APA, Harvard, Vancouver, ISO, and other styles

48

BregnhÃ¸j, A., and H. SÃ¸sted. "Type I ammonium persulfate allergy with no cross reactivity to potassium persulfate." Contact Dermatitis 61, no. 6 (December 2009): 356–57. http://dx.doi.org/10.1111/j.1600-0536.2009.01644.x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

49

Hu, Wei, Shen Xin Li, Wang Ying, and Cheng Duan Wang. "Decolourization of Kiscolon Scarlet 2KN by Persulfate." Advanced Materials Research 864-867 (December 2013): 256–60. http://dx.doi.org/10.4028/www.scientific.net/amr.864-867.256.

Full text

Abstract:

The decolourization of dye wastewater by persulfate was studied using kiscolon scarlet2KN as a model dye wastewater. Effects of several parameters, such as dose of oxidant, pH, temperature and UV irradiation, were investigated in detail. The results showed that the decolourization reaction of kiscolon scarlet2KN by persulfate could be fitted to a pseudo-first order kinetics model. In addition, when the oxidant amount used is 70 times of kiscolon scarlet2KN, pH 5.71 and reaction temperature for 70°C, kiscolon scarlet2KN decolorization rate can reach more than 98%. The results are useful for the treatment of dye wastewater.Keywords:Kiscolon scarlet 2KN, Decolourization, Persulfate

APA, Harvard, Vancouver, ISO, and other styles

50

Zhi, Keke, Zhe Li, Pengfei Ma, Yongxiang Tan, Yuefeng Zhou, Weikang Zhang, and Jingxing Zhang. "A Review of Activation Persulfate by Iron-Based Catalysts for Degrading Wastewater." Applied Sciences 11, no. 23 (November 29, 2021): 11314. http://dx.doi.org/10.3390/app112311314.

Full text

Abstract:

Advanced oxidation technology of persulfate is a new method to degrade wastewater. As the economy progresses and technology develops, increasingly more pollutants produced by the paper industry, printing and dyeing, and the chemical industry are discharged into water, causing irreversible damage to water. Methods and research directions of activation persulfate for wastewater degradation by a variety of iron-based catalysts are reviewed. This review describes the merits and demerits of advanced oxidation techniques for activated persulfate by iron-based catalysts. In order to promote the development of related research work, the problems existing in the current application are analyzed.

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Persulfate'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles