稻壳活性炭对废水中Cr(Ⅵ)的吸附

Adsorption of Cr(Ⅵ) on rice husk activated carbon in wastewater

利用农业废弃物稻壳为原材料制备活性炭,并对其吸附水中Cr(Ⅵ)的行为进行了研究.采用单因素法探索溶液pH值、稻壳活性炭投加量、吸附时间、反应温度等因素对吸附性能的影响,并对其动力学特性进行了研究.结果表明:稻壳活性炭对Cr(Ⅵ)的吸附在120 min到达平衡;pH对吸附率影响较大,当pH为2,温度为30℃时,对Cr(Ⅵ)的吸附率可达96%以上.动力学数据分析表明,吸附过程符合准二级动力学模型;等温吸附过程可以用Langmuir等温吸附方程来描述,吸附过程以单分子层吸附为主.

Activated carbon was prepared from rice husk,and the adsorption behavior of Cr(Ⅵ)on activated carbon in adsorbed water was studied.By single factor method the effects of pH value of solution,dosage of activated carbon from rice husk,adsorption time and reaction temperature on adsorption performance were investigated and the kinetic characteristics were studied.The results showed that Cr(Ⅵ)adsorption by activated carbon from rice husk reached equilibrium within 120 min,the adsorption rate of Cr(Ⅵ)can reach 96%when the pH is 2 and the temperature is 30℃.The adsorption process conforms to the quasi-second-order kinetic equation and follows Langmuir isotherm model.The monomolecular layer adsorption is predominant in the activated carbon adsorption process.