低分子有机酸对土壤氟吸附的影响

摘要

用等温平衡吸附法研究了柠檬酸、草酸对砂姜黑土和潮土氟吸附的影响，提出了有机酸影响氟吸附的可能机理。实验结果表明，有机酸对土壤氟吸附有较大的影响：(1)当有机酸处于低浓度时，土壤氟吸附量随浓度升高而增加；高浓度时，土壤氟吸附量随有机酸浓度升高而降低；(2)在有机酸存在条件下，土壤氟的吸附量与平衡氟浓度间呈极显著的直线正相关或负相关。%With the isothermal balance adsorption method,effect of citric acid and oxalic acid on fluoride adsorption by shajiang black soil and fluvio-aquic soil was investigated and their possible mechanism verified.The results showed that the effect was significant.(1)When the concentration of the organic acid was low,soil adsorption of fluoride rose with the concentration of the organic acid,and when the concentration of organic acids was high,it dropped with rise in the concentration,and (2)in the presence of the organic acids,soil adsorption of fluoride showed an extremely significant linear positive (or negative) correlationship with balanced fluoride concentration in the soil.