摘要
利用沉淀法制备了椰壳生物炭(CSB)与Fe3O4的复合物磁性椰壳生物炭(MCSB),并将其用于页岩气压裂返排液的研究。对MCSB进行结构表征,以TOC去除率作为评价指标,考察其对压返液的吸附效果。通过研究改性前后CSB的结构形貌、表面化学基团等物理结构,结果表明改性后的CSB依然具有多孔结构并且孔结构增多,其表面变得粗糙,表面积增大;且Fe-O键成功负载于表面,改性成功。MCSB制备最优条件为浸渍比率0.15,热解温度150℃,保留时间30 min,且对于MCSB吸附有机物的影响表现为:浸渍比率>保留时间>热解温度。通过响应面分析法优化吸附条件,获得MCSB处理压返液的最佳工艺条件:吸附时间90 min,搅拌强度104 r/min,吸附剂用量9 g/L。该条件下TOC去除率为61.00%,相较于CSB的TOC去除率增加23.00%。MCSB在处理废水后,经五次试验后依然具有最佳去除率的75.0%,MSCB通过外加磁场从水中分离并重复使用,可作为一种吸附剂有效去除水中的有机污染物,应用前景广阔。
The magnetic coconut shell biochar(MCSB), a composite of coconut shell biochar(CSB) and Fe3O4, was prepared by the precipitation method and used in the study of shale gas pressure fracturing flowback fluid.The MCSB were characterized and TOC removal rate was used as the evaluation index to investigate its adsorption effect on pressure return liquid.The results show that the modified CSB still had a porous structure and the pore structure increases, its surface became rough, and the surface area increased;and the Fe-O bond was successfully loaded on the surface. The optimal conditions for MCSB preparation were immersion ratio of 0.15, pyrolysis temperature of 150 ℃, retention time of 30 min, and the effect on the adsorption of organic matter by MCSB was: immersion ratio>retention time>pyrolysis temperature.The adsorption conditions were optimized by response surface analysis, and the best process conditions for MCSB treatment of pressure return liquid were obtained: the adsorption time was 90min, the stirring intensity was 104 r/min, and the amount of adsorbent was 9 g/L. The TOC removal rate under this condition was 61.00%, which was an increase of 23.00% compared to the TOC removal rate of CSB.After treating wastewater, MCSB still had the best removal rate of 75.00% after five tests. MCSB was separated from the water by an external magnetic field and reused. It can be used as an adsorbent to effectively remove organic pollutants in the water and has a broad application prospect.
作者
王兵
欧景菡
熊明洋
高春阳
曾瑶
唐鑫
WANG Bing;OU Jinghan;XIONG Mingyang;GAO Chunyang;ZENG Yao;TANG Xin(School of Chemistry and Chemical Engineering of Southwest Petroleum University;Key Laboratory of Environmental Pollution Prevention on Oil and Gas Fields and Environmental Safety in Sichuan,Chengdu 610500,China)
出处
《水处理技术》
CAS
CSCD
北大核心
2022年第4期30-35,共6页
Technology of Water Treatment
基金
国家科技重大专项(2016ZX05062)。
关键词
椰壳炭
改性
压返液
有机物
coconut shell charcoal
modification
pressure return liquid
organic matter
