论文部分内容阅读
采用批量平衡实验,研究阳离子表面活性剂十六烷基三甲基铵离子(HDTMA)改性的zeo-HDTMA(有机沸石)、mont-HDTMA(有机蒙脱土)和atta-HDTMA(有机凹凸棒土)及其原粘土对典型有机氯农药DDT代谢产物p,p’-DDE的吸附解吸特性。结果表明,随原粘土阳离子交换容量(CEC)的增大,有机粘土吸附量增大,且有机粘土的吸附量比原粘土大大提高;有机粘土和原粘土对p,p’-DDE的吸附能力顺序为:zeo-HDTMA>mont-HDTMA>atta-HDTMA≥mont(蒙脱土)>atta(凹凸棒土)>zeo(沸石),这一顺序与它们的有机碳质量分数大小顺序一致。原粘土对p,p’-DDE的吸附等温线符合Langmuir吸附等温方程,吸附呈单分子层形式,且存在竞争吸附;有机粘土对p,p’-DDE的吸附等温线符合Linear吸附等温方程,吸附是p,p’-DDE在有机粘土中有机相的分配所致。当CaCl2质量浓度从0增加到50g/L时,mont-HDTMA对p,p’-DDE吸附量提高了10.3%。有机粘土和原粘土对p,p’-DDE的解吸率大小顺序为:zeo>atta>mont>atta-HDTMA>mont-HDTMA>zeo-HDTMA,这一顺序与它们的有机碳质量分数大小顺序相反。
Mass balance experiments were conducted to study the effects of cetyltrimethylammonium ion (HDTMA) modified zeo-HDTMA (organic zeolite), mont-HDTMA (organic montmorillonite) and atta-HDTMA Soil) and its original clay on the adsorption and desorption properties of the DDT metabolites p, p’-DDE of typical organochlorine pesticides. The results show that with the increase of cation exchange capacity (CEC) of original clay, the adsorption capacity of organic clay increases and the adsorption capacity of organic clay increases greatly compared with that of original clay. The adsorption capacity of organic clay and original clay to p, p’-DDE The order is: zeo-HDTMA> mont-HDTMA> atta-HDTMA≥mont (montmorillonite)> atta (attapulgite)> zeo (zeolite) in the same order as their organic carbon mass fractions. The adsorption isotherms of p, p’-DDE in the original clay accorded with the Langmuir adsorption isotherm equation, and the adsorption was in the form of monolayer with competitive adsorption. The adsorption isotherms of p, p’-DDE for organoclay accorded with the linear adsorption isotherm equation, Adsorption is p, p’-DDE due to the distribution of the organic phase in the organoclay. When CaCl2 concentration increased from 0 to 50 g / L, the adsorption capacity of p, p’-DDE by mont-HDTMA increased by 10.3%. The order of desorption rates of p, p’-DDE for organoclay and original clay is: zeo> atta> mont> atta-HDTMA> mont-HDTMA> zeo-HDTMA in reverse order of their organic carbon mass fractions .