粉末活性炭吸附2,4,6三氯酚的性能研究

Performance of 2,4,6trichlorophenol Adsorption by Powdered Activated Carbon

摘要:

针对粉末活性炭PAC吸附2,4,6三氯酚(2,4,6TCP)的性能进行了研究.考察了PAC炭种、投加量和温度3因素对2,4,6TCP吸附效果的影响;建立了吸附动力学、等温吸附线以及吸附热力学模型;研究了PAC与预氧化联用技术对2,4,6TCP的协同去除作用.结果表明,上述3个因素对2,4,6TCP吸附效果影响均显著,其中PAC投加量的影响最大,PAC炭种其次,温度的影响最小.PAC可以快速有效地吸附水中的2,4,6TCP,快速吸附期在前20 min,吸附容量可达到80%以上.拟二级动力学模型和Freundlich吸附等温线模型可分别较好地描述PAC对2,4,6TCP的吸附行为.PAC吸附2,4,6TCP的过程为自发、放热以及熵减的过程.PAC与预氧化联用技术可以提高对2,4,6TCP的处理效果.

Abstract:

The performance of 2,4,6trichlorophenol (2,4,6TCP) adsorption by powdered activated carbon (PAC) was investigated in aqueous solutions to evaluate the effects of PAC species,PAC dosage and temperature on the adsorption of 2,4,6TCP by PAC.The adsorption kinetics,thermodynamics and isothermal models were established.The removal efficiencies of 2,4,6TCP by the combination of PAC adsorption and preoxidation were figured out.The results indicate that the effects of all the three factors on adsorption of 2,4,6TCP are significant and follow the order of PAC dosage> PAC species> temperature.The PAC adsorption is an effective method to remove 2,4,6TCP.The adsorption rate of 2,4,6TCP by PAC is rapid and more than 80% adsorption capacity of PAC can be reached within the initial 20 min.The adsorption behaviors can be well described by pseudo second order adsorption kinetic model and Freundlich adsorption isotherm model.The adsorption of 2,4,6TCP by PAC is spontaneous,exothermic and entropy decreasing.The combination of PAC adsorption and preoxidation can enhance the removal of 2,4,6TCP.