微囊藻毒素MC-RR在农田土壤中吸附行为研究  

Sorption of microcystin-RR in agricultural soils

作　　者：邓哲深 向垒[1,2] 莫测辉[1,2] 黄缤慧 温宏飞[1,2] 陈雷[1,2] 蔡全英[1,2] 李彦文[1,2] 

机构地区：[1]广东省环境污染控制与修复材料工程中心,广州510632 [2]暨南大学环境学院,广州510632

出　　处：《环境科学学报》2016年第12期4482-4489,共8页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金(No.41301337);广东省自然科学基金团队项目(No.2016A030312009);广东省科技计划项目(No.2013 B090600143;2016 B020242005;2015 B090903070;2015 B020235008)~~

摘　　要：采用批处理实验研究了典型微囊藻毒素MC-RR（10-400μg·L^-1）在农田土壤（水稻土、赤红壤和咸田土）中的吸附动力学和热力学特征．并探讨土壤理化性质对其吸附行为的影响．结果表明。MC-RR在农田土壤中的吸附均于4h内达到平衡，吸附动力学均符合拟二级动力学方程（R^2〉O．994），液膜扩散是主要控速过程；各温度下（15、25、35℃）MC-RR吸附等温线均符合Langmuir方程（R^2〉0．827）．水稻土吸附MC-RR主要为自发放热的物理吸附过程，其吸附能力随温度升高而降低；赤红壤和咸田土吸附MC．RR主要为自发吸热的化学吸附过程，其吸附能力随温度升高而增强．土壤粘粒矿物和有机质含量显著影响其对MC-RR的吸附能力，粘粒矿物含量越高，有机质含量越低，MC-RR吸附能力越强．MC-RR在有机质含量较高的水稻土中难吸附．而在有机质含量较低的赤红壤和粘土含量较高的咸田土中易吸附．Sorption characteristics of microcystin （MC-RR） in agricultural soils （paddy soil, latosolic red soil, and salted paddy soil） were investigated using batch sorption experiments. Furthermore, the effects of soil physicochemical properties on the MC-RR sorption were also studied in the present study. Results showed that the sorption of MC-RR in the soils reached equilibrium within 4 h. The sorption kinetics of MC-RR followed the pseudo-second-order kinetic models with R2〉0.994 and they were controlled by the liquid film diffusions. The MC-RR sorption isotherms followed the Langmuir models well with R2 〉0.827 under different temperature （ 15,25,35 ℃ ）. The MC-RR sorption in paddy soil was a spontaneous, exothermic, and physical sorption process, and the sorption decreased as the temperature rises. However, the MC-RR sorption in latosolic red soil and salted paddy soil were spontaneous, endothermic, and chemical sorption processes, and the sorption increased with temperature. Soil clay contents and organic matters played a predominant role in MC-RR sorption process, with the promotion effect and inhibition effect, respectively. Therefore, MC-RR was easily sorbed by latosolic red soil （with lower organic matter） and salted paddy soil （with higher clay content）, while it was hardly sorbed by paddy soil （with higher organic matter）.

关 键 词：微囊藻毒素MC-RR 农田土壤 吸附 动力学 等温线 

分 类 号：X53[环境科学与工程—环境工程]