苯酚在竹炭上的吸附平衡和动力学研究

Adsorption equilibrium and dynamics of phenol on bamboo charcoals

研究了20℃下苯酚在3种竹炭上的吸附平衡和动力学。采用低温下氮气吸附法测定了3种竹炭的BET比表面积和孔径分布,并用SEM观察了其微观形貌。根据Langmuir吸附等温线模型和Freundli ch模型分别对吸附数据进行拟合,结果表明Freundli ch吸附等温线模型能较好的用来描述苯酚在竹炭上的吸附平衡,并确立了20℃下苯酚在竹炭上吸附的Freundlich模型表达式;竹炭的BET比表面积和中孔容积越大,饱和吸附量也越大;对同一种竹炭,随竹炭用量的增加,溶液中苯酚残余浓度就越低,而竹炭用量与达到饱和吸附的时间无关。

The adsorption equilibrium and dynamics of phenol on three different bamboo charcoals have been measured. The BET specific surface areas and pore size distributions are determined by physical adsorption of N2 at 77 K. At the same time, the morphologies are observed by scanning electron microscopy (SEM). According to Langmuir adsorption isotherm model and Freundlich model, the equilibrium adsorption data are fitted by the least square method. The research results suggest that the freundlich adsorption isotherm model can be properly used to formulate the adsorption behavior of phenol on bamboo charcoals. With the increasing of BET surface area and mesopore volume, the saturated adsorption amount increases greatly. As for the same type of bamboo charcoal, the residual density decreases as the consumption amount increases. But the consumption amount of bamboo charcoal has no effect on the time when the system reaches equilibrium.