Activated carbon,as the cadmium adsorbent,loaded with manganese oxide,was prepared by impregnated-roasting method.The optimal preparation conditions determined by orthogonal experiment were as follows:Impregnation time of 7 h,KMnO4 mass fraction of 2.7％,roasting temperature of 470 ℃,roasting time of 2.5 h.The modified activated carbon was characterized by BET,SEM,FTIR and XRD.The adsorption effect of Cd(Ⅱ) was researched as a function of various factors such as pH,adsorbent time,initial concentration and adsorbent temperature.The results indicated that the amount of oxygencontaining functional groups increased and MnO2 was loaded on modified activated carbon.The adsorption capacity of the MOAC could reach 84.15 mg/g under the conditions of the adsorbent dosage of 0.5 g/L,the initial Cd(Ⅱ) concentration of 50 mg/L,pH of 6.0,adsorption temperature of 298 K,and the adsorption time of 12 h.The adsorption process fit the pseudo-second-order and Langmuir equation.Thermodynamic parameters revealed that the cadmium adsorption process was exothermic and spontaneous.%采用浸渍焙烧法制备了活性炭负载氧化锰的除镉(Cd(Ⅱ))吸附剂,通过L9(34)正交试验确定最优制备条件如下:浸渍时间7h,KMnO4质量分数2.7％,焙烧温度470℃,焙烧时间2.5h.通过BET、SEM、FTIR、XRD对改性活性炭(MOAC)进行表征,研究了pH值、吸附时间、初始浓度、吸附温度等对Cd(Ⅱ)吸附效果的影响.结果表明:MOAC表面烃基合氧官能团增多,氧化锰以MnO2的形式负载到其表面;当MOAC的投加量为0.5 g/L,Cd(Ⅱ)的初始浓度为50 mg/L,溶液pH值为6.0,温度为298 K,吸附时间为12 h时,MOAC对Cd(Ⅱ)的吸附量高达84.15 mg/g,吸附过程符合准二级动力学方程和Langmuir等温吸附方程,热力学参数表明该吸附过程为放热、自发的过程.
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