甲壳素与氯基苯酚的吸附性能研究

以片状甲壳素(聚氨基葡萄糖)为研究对象,探讨了不同温度(5,15,25℃)下五氯酚(PCP)的吸附动力学;考察了温度(5,15和25℃)、盐度(w(NaCl)为0～7%)、pH值(pH5～8)、氯原子取代等对氯酚吸附的影响;比较了5℃时7种氯酚(PCP,三氯酚(2,4,6-TCP),4种二氯酚(2,5-DCP,3,4-DCP,2,3-DCP,2,6-DCP)和单氯酚(3-MCP))的吸附容量。结果表明,低温使五氯酚在片状甲壳素上的吸附速率显著降低,但同时增加甲壳素的吸附容量;5℃条件下,pH>6 5时,PCP吸附量降低一半后趋于稳定;w(NaCl)高于1%时,几乎完全抑制了PCP的吸附。7种氯酚在片状甲壳素上的吸附量大小顺序为PCP>TCP>DCP>MCP,其中4种DCP具有相似的吸附性能。 

Study on Sorption Properties of Chlorophenols onto Chitosan

The slice chitosan was used to study the sorption dynamics of pentachlorophenol (PCP) under different temperatures (5, 15 and 25 ℃). The influences of temperature (5, 15 and 25 ℃), salinity w(NaCl)(0～7%), pH value (5～8) and chlorine atom substitution on the sorption of chlorophenols were investigated, and the uptake capability of seven kinds of CPs, i.e. PCP, 2,4,6-TCP, 2,5-DCP, 3,4-DCP, 2,3-DCP, 2,6-DCP and 3-MCP, compared under the temperature of 5 ℃. It was showed that lower temperature markedly decreased the adsorption rates, but elevated the maximum PCP uptake capacities on the polymer. PCP uptake capacity was halved at pH levels higher than 6.5 under the temperature of 5 ℃, and w(NaCl) greater than 1% blocked PCP sorption almost completely. Of the seven kinds of chlorophenols, PCP has the maximum uptake capacity, followed by TCP, DCP, and finally MCP. The four kinds of DCP, with the same elemental compositions, achieved similar sorption performances.