农药涕灭威在土壤中的不可逆吸附行为

Study on irreversible behavior of pesticide-aldicarb in soil

应用多循环吸附 /脱附实验法 ,分 4个浓度范围对 0— 1 80 0mg/L浓度范围内的氨基甲酸酯农药涕灭威在土壤中的吸附 /脱附行为进行了研究 .发现涕灭威在土壤中会发生不可逆吸附现象 ,其在土壤中的总吸附量可由两部分组成 :可逆吸附量 ( qrev)和不可逆吸附量 ( qirr) ,其在土壤中的最大不可逆吸附量 ( qirrmax)为 1 52 35mg/kg .在较低浓度下 ,每次吸附约有超过70 %的农药进入不可逆吸附室 ,但在较大浓度下 ,不可逆吸附室可在一步吸附过程中达饱和 .

The sorption/desorption behavior of carbamate pesticide——aldicarb in soil has been studied with the concentration range of 0—1800 mg/L by multiple cycles of adsorption/desorption experiments.Irreversible sorption of aldicarb was found In all 4 experiments The total sorption amount ( q total ) included two parts:reversible sorption amount ( q rev ) in the labile compartment and irreversible sorption amount ( q irr ) in the irreversibly sorbed compartment.The maximum irreversible adsorption concentration of aldicarb in soil ( q irr max ) was 152 35?mg/kg.In every case,a fraction of aldicarb was adsorbed irreversibly and over 70% of the adsorbed mass resided in the irreversibly sorbed compartment in the situation of low initial concentration.But in higher initial concentration the irreversibly sorbed compartment could be filled in one sorption step.