污泥基生物炭对重金属的吸附作用  

Adsorption of heavy metals by biochar derived from municipal sewage sludge

作　　者：陈坦[1] 韩融[2] 王洪涛[1] 陆文静[1] 张远澄 周泽宇[1] 

机构地区：[1]清华大学环境学院,北京100084 [2]长安大学环境科学与工程学院,西安710064

出　　处：《清华大学学报（自然科学版）》2014年第8期1062-1067,共6页Journal of Tsinghua University(Science and Technology)

基　　金：国家水体污染控制与治理科技重大专项资助项目(2011ZX07317-001);国家自然科学基金资助项目(41371472)

摘　　要：为研究市政污泥基生物炭对重金属的吸附性能,进而作为吸附材料应用于污染修复中,在900℃下无氧热解制备生物炭,利用静态平衡法测定生物炭对重金属Pb、Zn、Cu、Cd的吸附效果。结果表明：污泥基生物炭具有良好的吸附性能,吸附容量比市售活性炭高一个数量级,对Pb、Zn、Cu、Cd的最大吸附量实测值分别为（104.15±1.60）mg/g、（36.05±0.87）mg/g、（41.30±1.38）mg/g和（37.17±2.59）mg/g。污泥基生物炭具有很强的pH缓冲能力,平衡后溶液pH值大幅提高约2-3,溶液可由酸性变为近中性甚至碱性。平衡过程中,污泥基生物炭可释放大量的Ca2＋离子,释放量与重金属离子初始质量浓度正相关,在0.2%污泥基生物炭投加、重金属质量浓度250mg/L以内时,Ca2＋离子质量浓度为32.07-72.86mg/L。污泥基生物炭具有很强的重金属吸附能力,主要吸附机理为表面沉淀和离子交换。The heavy metals adsorptive ability of municipal sewage sludge derived biochar was investigated to develop an adsorbent for remediation contamination.The biochar was produced with pyrolysis at 900 ℃ without oxygen,with static equilibrium experiments conducted to evaluate the adsorptive effect of the biochar for heavy metals Pb,Zn,Cu and Cd.The results show that the sludge-derived biochar has strong adsorption ability that is an order of magnitude higher than that of commercial activated carbon,with maximum measured values of（104.15 ± 1.60）mg/g for Pb,（36.05 ±0.87）mg/g for Zn,（41.30 ± 1.38）mg/g for Cu and（37.17 ±2.59）mg/g for Cd.The sludge-derived biochar also has a high pH buffer capacity.The pH of equilibrium adsorption solutions may increase significantly by 2 - 3,with acidic solutions changed into approximately neutral or even alkaline solutions.The sludge-derived biochar can release a large amount of Ca2＋ions,which positive correlation with the initial heavy metal concentration with an additional biochar dosage of 0.2%,and a heavy metal concentration of 250mg/L,the Ca2＋concentration increased from 32.07 to 72.86mg/L.Sludge-derived biochar is an excellent material with strong heavy metal adsorptive ability and the main adsorption mechanism is surface precipitation and cation exchange.

关 键 词：市政污泥 热解 生物炭 重金属 吸附 

分 类 号：X705[环境科学与工程—环境工程]