改性核桃壳/活性炭复合吸附制革废水中Cr^(6+)效果及动力学研究

Study on Adsorption Effect and Kinetics of Modified Walnut Shell/Activated Carbon on Wastewater Containing Cr^(6+)

以废弃核桃壳为原料,采用磷酸对其进行改性,和活性炭复合使用吸附制革废水中的Cr^(6+),并对其吸附动力学进行研究。实验结果表明:当改性核桃壳/活性炭质量比为1∶1,添加量1.6 g,pH为2,吸附温度30℃的条件下,吸附40 min就达到饱和吸附状态,对Cr^(6+)的吸附率达99.44%,效果优于单独使用改性核桃壳和活性炭,吸附时间短,吸附率高。改性核桃壳-活性炭复合吸附剂对Cr^(6+)的吸附过程可用一级动力学模型来模拟,模型拟合度高,相关系数达R^2=0.99565。

The waste walnut shell was modified by phosphoric acid to adsorb Cr6+with activated carbon in tannery wastewater,and its adsorption kinetics was studied.The experiment results showed that when the mass ratio of modified walnut shell/activated carbon of 1∶1,dosage of 1.6g,pH=2,adsorption temperature of 30℃,adsorption time of 40min,which reached saturation adsorption conditions,the adsorption rate of Cr6+was 99.44%.The adsorption effect was better than use of modified walnut shell or activated carbon,which had obvious advantages that adsorption time was shorter,the adsorption rate was higher.The adsorption process of modified walnut shell-activated carbon composite adsorbent for Cr6+could be simulated by first order kinetic model,and the model correlation coefficient was 2=0.99565.