有机改性凹凸棒土对腐殖酸的吸附性能研究

合成了十六烷基三甲基氯化铵(CTAC)改性的凹凸棒土吸附剂,并研究了其对水中腐殖酸的吸附行为。通过FTIR、TG对改性前后凹凸棒土进行表征。结果表明,十六烷基三甲基氯化铵成功结合到凹凸棒土表面,结合到凹凸棒土表面的量为9.78%。在25℃时,腐殖酸在吸附剂上吸附行为符合Freundlich方程,吸附动力学符合拟二级动力学方程,初始浓度为54.60~200.20mg/L时,ATP-CTAC对腐殖酸的最大吸附量为253mg/g;温度对吸附行为影响不大;改性后的凹凸棒土对腐殖酸的吸附随pH的增大而降低;改性后的凹凸棒土显著地提高了对腐殖酸的吸附量。

ADSORPTION BEHAVIOR OF HUMIC ACID BY ORGANIC MODIFIED ATTAPULGITE

Attapulgite clay was modified by cetyltimethyl ammonium chloride(CTAC),and its adsorption behaviors for humic acid in aqueous solution was investigated.The natural and modified attapulgite characterizations were investigated using FITR and TG.Characterized results of the natural and modified attapulgite showed that cetyltrimethyl ammonium chloride was successfully grafted on the surface of ATP and the amount combining to ATP surface was 9.78%.Humic acid adsorption onto the ATP-CTAC was fitted to Freundlich isotherm model,and adsorption kinetics could be well described with pseudo-second-order kinetic model.The maximum amount of humic acid onto ATP-CTAC was 253mg/g with the initial concentration rang from 54.60mg/L to 200.20mg/L.No obvious change of humic acid adsorption amount was found with increasing temperature.Adsorption amount of humic acid onto ATP-CTAC decreased with the increasing of pH values.Compared with the natural attapulgite,the modified attapulgite remarkably improved the adsorption amount of humic acid.