钢渣滤料对磷的吸附动力学和热力学

摘要

以钢渣为主要原料，添加少量粘土和造孔剂制备钢渣滤料。通过批次吸附实验，研究了钢渣滤料对废水中磷的吸附特性。结果表明，不同温度条件下钢渣滤料对磷的吸附过程均符合准二级反应动力学方程，反应的活化能＞40kJ/mol。等温吸附过程符合Langmuir方程，在20℃、30℃和40℃时的最大吸附量分别为1．166、1．826和2．422 mg/g。热力学参数△G0、△H0和△S0表明，该过程是自发、吸热、熵增型反应，且磷的吸附以化学吸附为主。%Slag filter material made from steel slag and clay was used for phosphate adsorption ,and adsorption char-acteristic was studied by batch experiments .Results showed that the uptake of phosphate on slag filter material at different temperature fitted with pseudo-second-order model,and the activation energy was more than 40kJ/mol.In addition,isotherm adsorption data on slag filter material followed the Langmuir model well ,and the maximum ad-sorption capacity at 20℃,30℃and 40℃were 1.166,1.826 and 2.422mg/g,respectively.Thermodynamic param-eters△G0 ,△H0 and△S0 showed that the adsorption was spontaneous , endothermic and entropy increase process and chemical adsorption was dominant for phosphate uptake .