pH值对土壤吸附二氯喹啉酸的影响研究

Effect of pH Value on Dichloro-Quinolinic Acid of Soil Adsorption

采用间歇平衡震荡法研究pH值对二氯喹啉酸在红土、黑土、潮土三种供试土壤中吸附特征。结果表明:二氯喹啉酸在不同土壤中的吸附特征存在差异,土壤的pH值影响二氯喹啉酸的吸附特征,当pH值趋近于二氯喹啉酸的pKa(4.35)时,容易被土壤吸附;pH值在较高情况下(pH=7.4),二氯喹啉酸大多呈离子状态,不易被土壤吸附;有机质含量降低将导致土壤对二氯喹啉酸的吸附能力下降。

The paper uses the intermission, equilibrium and shaking process to explore the pH value on the adsorption characteristics of dichlor-quinolinic acid in different soils, namely red earth, black earth and tide (fluvo-aquic) soil, respectively. The result shows that the adsorption characteristics of dichloro-quinolinic acid in different soils have differences, and the pH values in the soils affect the adsorption characteristics of dichloro-quinolinic acid. When the pH value tends towards pKa (4.35) of dichloro-quinolinic acid, the dichloro-quinolinic acid is easily absorbed by the soils. When pH value is under the higher instance (pH=7.4), the dichloro-quinolinic acid assumes the ion estate and can hardly be absorbed by the soils;Meantime, the reduction of the organic matter content will lead to decline the adsorption capability of the soils upon the dichloro-quinolinic acid.