磷酸活化-微波热解改性污泥对镉的吸附性能

Adsorption of modified municipal sludge with phosphoric acid activation and microwave pyrolysis on Cd^(2+) ions

以城市污水处理厂剩余污泥为原料,利用磷酸活化-微波热解制取改性污泥。以此污泥作为吸附剂,对含Cd2+废水进行了吸附实验研究。考察了溶液反应时间、Cd2+浓度、pH值和吸附剂用量对镉吸附去除效果的影响;利用等温吸附实验作出吸附等温线,并考察了改性污泥吸附剂吸附Cd2+的动力学方程。实验结果表明,改性污泥对Cd2+有良好的吸附性能,吸附最佳pH值为6.0,吸附较好地符合一级动力学吸附模型和Langmuir-Freundlich等温吸附方程,吸附为物理吸附,吸附反应发生12 h后达到吸附平衡。

Modified sludge was prepared with phosphoric acid activation and microwave pyrolysis by use of municipal sludge as raw material. The application of this sludge used for adsorbing Cd2 +was studied. The effects of reaction time,initial concentrations of Cd2 +,the initial pH and adsorbent dosage on the adsorption capacity were investigated. The absorption isotherm was drawn and the dynamics equation was also studied. The results showed that the adsorption performance of modified carbon made from municipal sludge is better. The optimum pH value is 6. 0. The experimental data well fit the first-order kinetics process and Langmuir-Freundlich equations. The reactive process is physical adsorption. The adsorption equilibrium time for modified sludge adsorbing is 12 hours.