改性污泥生物质炭的制备及其对水中铜和铬的去除

Preparation of modified sludge biochar and its removal of copper and chromium from water

为了获得污泥生物质炭对水中铜和铬的最大吸附量,采用控制变量的实验设计方法得到了污泥生物质炭改性材料的最优制备条件:氯化锌与污泥质量比为1∶1、炭烧温度400℃。结果表明:污泥生物质炭对铜和铬的处理效果相对原污泥有显著提升;最佳反应pH值分别为4和9;Langmuir方程能够更好地描述污泥生物质炭对铜和铬的等温吸附过程,二者均为低温自发放热反应;在pH值为7的条件下,污泥生物质炭对水中铬和铜的吸附分别在反应开始后的2 h和4 h内基本达到平衡,吸附动力学符合准二级反应模型。污泥生物质炭改性材料可能成为处理含铜、含铬类废水的新型吸附剂。

In order to obtain the maximum adsorption capacity of sludge biochar for copper and chromium,the optimal preparation conditions of sludge biochar modified materials were obtained by using the experimental design method of controlling variables:the ratio of zinc chloride to sludge material was 1∶1,and the carbonization temperature was 400℃.The experimental results showed that the treatment effect of sludge biomass charcoal on copper and chromium was significantly improved compared to the original sludge.And the optimal reaction pH was 4 and 9,respectively.The Langmuir equation can better describe the isotherm adsorption process of copper and chromium by sludge biomass charcoal,which were both of low-temperature spontaneous heat reactions.Under the condition of pH was 7,the adsorption of chromium and copper in water by sludge biomass charcoal basically reached equilibrium within 2 h and 4 h after the reaction started,and the adsorption kinetics was combined with a pseudo-secondary reaction model.Sludge biomass charcoal modified materials may become a new type of adsorbent for treating wastewater containing copper and chromium.