污泥基生物炭的制备及其对重金属的吸附性能

Preparation of Sludge Biochar and Its Adsorption to Heavy Metals

本研究采用城市生活污泥为原料,污泥活化后低温炭化所得的生物炭用作吸附剂去除水溶液中的Pb^(2+)、Cu^(2+)、Cd^(2+)、Cr^(6+)重金属离子。并对所得生物炭进行了表征,研究了溶液pH值、初始浓度、吸附时间对生物炭吸附能力的影响,并对吸附机理进行了分析。实验结果表明:所得生物炭对Pb^(2+)、Cu^(2+)、Cd^(2+)、Cr^(6+)的最大吸附值分别为250 mg/g、93.5 mg/g、44.4 mg/g、142 mg/g。生物炭对Pb^(2+)、Cu^(2+)、Cd^(2+)、Cr^(6+)的等温吸附曲线符合Langmuir方程,吸附动力学过程可以用伪二阶模型来描述。

In this study, the sludge biochar was used as an adsorbent to remove Pb2＋, Cu2＋, Cd2＋, Cr6＋ heavy metal ions from aqueous solution. The biochar was characterized and the effects of pH value, initial concentration and adsorption time on the adsorption capacity of biochar were studied, and the adsorption mechanism was analyzed. The experimental results show that the maximum adsorption for Pb2＋, Cu2＋, Cd2＋, Cr6＋ reached 250 mg/g, 93.5 mg/g, 44.4 mg/g and 142 mg/g, respectively. The Langmuir adsorption isotherm was applicable fit adsorption process, and adsorption kinetic process could be described by the pseudo-second-order model.