Co-Authors:
Saltzman, S., Division of Soil Residues Chemistry, Institute of Soils and Water, Volcani Center, Bet Dagan, Israel
Mingelgrin, U., Division of Soil Residues Chemistry, Institute of Soils and Water, Volcani Center, Bet Dagan, Israel, Department of Chemical Physics, Weizmann Institute of Science, Rehovot, Israel
Yaron, B., Division of Soil Residues Chemistry, Institute of Soils and Water, Volcani Center, Bet Dagan, Israel
Abstract:
Oven-dried kaolinite has a catalytic effect upon parathion and methylparathion hydrolysis. Addition of water to kaolinite, in the limits of sorbed water, affected the degradation kinetics of both insecticides and increased the degradation rate. A slight increase in the moisture content above that corresponding to sorbed water results in a steep decrease in the degradation rate. Following hydrolysis, part of the organophosphate hydrolysis product is fixed at the clay surface. The data obtained suggest that water molecules associated with the exchangeable cations participate in the hydrolysis.