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Your search keyword '"Pan, Xiangrui"' showing total 5 results
Start Over Author "Pan, Xiangrui" Publisher elsevier b.v.
5 results on '"Pan, Xiangrui"'

3. Integration of wastewater treatment units and optimization of waste residue pyrolysis conditions in the brominated phenol flame retardant industry.

Author

Liu, Shiqi, Hou, Xiangting, Yu, Chengze, Pan, Xiangrui, Ma, Junhao, Liu, Guocheng, Zhou, Chengzhi, Xin, Yanjun, and Yan, Qinghua

Subjects
WASTEWATER treatment, FIREPROOFING agents, HAZARDOUS wastes, WASTE treatment, ORGANIC wastes, HEXABROMOCYCLODODECANE, SODIUM sulfate, HAZARDOUS waste management
Abstract

[Display omitted] • An efficient production process of TBBPA has been developed by regulating the process parameters. • A high-value process of waste water/residues in the TBBPA production process was proposed. • Water and chlorobenzene can be recovered and reused through cleverly designing wastewater. • The pyrolysis removes organic impurities in waste residue while obtaining Na 2 SO 4 products. Among the bromine flame retardants, tetrabromobisphenol A (TBBPA) is a highly effective flame retardant that can be used as both reactive and additive. However, the synthesis reaction of TBBPA has a low conversion rate and many brominated phenolic organics. Therefore, there is an urgent need to remove brominated organic pollutants produced in the process of producing flame retardants to reduce the harm to the environment and human beings and to reduce production costs. In this study, an efficient process was developed to treat the wastewater and waste residue generated in TBBPA production process, realizing its harmless and resource utilization. In the resource utilization system, through the ingenious design of solution mixing, precipitation separation, three-effect evaporation and concentration, valuable substances were extracted to realize the recovery and reuse of wastewater. In the harmless utilization process of hazardous waste residue, through high-temperature pyrolysis at 500 °C for 2 h after optimization with hypoxia-hyperoxia atmosphere modulation, it can avoid the production of dioxins and carbon black, effectively remove the organic impurities, realize the harmlessness and obtain high-quality sodium sulfate. This paper aims to propose a simple, efficient and feasible utilization system, including the three major technological processes of TBBPA production, integrated wastewater treatment and optimized the harmless treatment of waste residue to obtain sodium sulfate, so as to realize TBBPA green production. Compared with the traditional TBBPA synthesis system, wastewater and waste residue treatment processes, the TBBPA quality is increased by 2 % and the economic cost is reduced by 10 %, which is of great significance to the development of the industry. [ABSTRACT FROM AUTHOR]

Published
2022
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5. Effects of feedstock and inherent mineral components on oxidation resistance of biochars.

Author

Liu, Guocheng, Pan, Xiangrui, Ma, Xiaohan, Xin, Shuaishuai, and Xin, Yanjun

Abstract

Chemical stability assessment of biochar has been universally used to indicate its potential of long-term carbon sequestration. The comparative study on oxidation resistance of biochars from diverse series of feedstock is relatively limited, as well as the effects of endogenous minerals on biochar stability. Herein, oxidation resistance of biochars from peanut shell, bamboo, saw dust, reed stalk, furfural residues, seaweed degumming residues and Enteromorpha prolifera at 500 °C (PS500, BB500, SD500, RS500, FR500, SR500 and EP500) was examined by the treatments of H 2 O 2 , K 2 Cr 2 O 7 and thermogravimetric analysis (TGA). Under H 2 O 2 or K 2 Cr 2 O 7 condition, C loss of algae-derived biochars (SR500 and EP500) was extremely greater than that of other biochars due to higher content of labile carbon components. PS500, BB500, SD500, RS500 and FR500 characterized with similar properties in carbon fraction, but they exhibited different ability to resist oxidation. The mineral fraction of biochars (e.g., content and species) varied with the feedstock, which played complex effects on the oxidation resistance. The mineral decomposition (e.g., CaCO 3) in EP500 and SR500 above 500 °C influenced the analysis of biochar stability by TGA. After acid-washing, EP500 and SR500 showed weaker thermal oxidation resistance, agreed with the results of H 2 O 2 and K 2 Cr 2 O 7 oxidation. The oxidation resistance of biochars was correlated better with O/C ratio, implying that O/C ratio was more robust indicator than other indexes (e.g., H/C ratio and the ratio of D band to G band of Raman). The FTIR, Raman and XPS results further demonstrated the elimination of aliphatics and amorphous aromatics and/or the carboxylation/carbonylation of aromatic structures by H 2 O 2 and K 2 Cr 2 O 7. These findings are useful for better understanding the impacts of feedstock and inherent minerals on the oxidation resistance of biochars. Unlabelled Image • Oxidation resistance of biochars from diverse series of feedstock was examined. • C loss of algae-derived biochars was extremely higher in H 2 O 2 /K 2 Cr 2 O 7 oxidation. • Mineral decomposition above 500 °C influenced biochar stability assessment by TGA. • The minerals derived from feedstock showed different effects on biochar stability. • O/C ratio was more robust indicator for biochar stability than H/C and ID/IG ratio. [ABSTRACT FROM AUTHOR]

Published
2020
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