活性炭纤维对废水中对硝基苯酚的吸附特性研究

Adsorption Characteristics of p-nitrophenol in Wastewater by Activated Carbon Fiber

对硝基苯酚(p-nitrophenol,PNP)毒性大、难于生物降解,是化工、农药、染料等行业废水中常见的有机污染物。利用静态吸附研究了活性炭纤维(Activated Carbon Fiber,ACF)对PNP的吸附特性。结果表明,伪二级动力学模型可以更好地对吸附过程进行拟合,吸附过程中可能发生外部液膜扩散、表面吸附和颗粒内部扩散;吸附热力学模型Freundilich和Dubinin-Radushkevich能够更好地描述ACF对PNP的吸附过程,说明ACF上的吸附位是不均匀的,可能会发生多层吸附,ACF对PNP的吸附以化学吸附起主导作用。

The toxic and biorefractory pollutant p-nitrophenol （PNP）widely exists in wastewater, such as chemical, pesticides and dyes wastewater.The adsorption characteristics of PNP by activated carbon fiber （ACF）in wastewater were investigated.Based on the static state adsorption technique,the adsorption thermo-dynamics and adsorption kinetics characteristics of PNP on ACF were also studied.The resuhs showed that pseudo-second order kinetic model was more suitable to describe the adsorption process of PNP,and external liquid film diffusion, surface adsorption, and intemal diffusion of particles might also occur in the adsorption process.Isotheml adsorption of PNP was best described by Freundlich and Dubinin-Radushkevich models,suggesting that the adsorption sites on ACF surface were heterogeneous;and thus muhilayer adsorption would occur.Chemisorption was the main pathway for PNP adsorption onto ACF.