RETENTION AND SEPARATION BEHAVIOR OF SOME ORGANOPHOSPHORUS AND PYRETHROID INSECTICIDES ON POLYURETHANE FOAMS

The application of polyurethane foam for the preconcentration of Cyper methrin, Malathion and Parathion insecticides was examined by the stat ic mode of extraction. The retention of the tested species from aqueou s media with the polyether polyurethane foam suggests that the solvent extraction and the cation chelation mechanism might be operative. Qua ntitative retention and recovery of the tested insecticides by the foa m column mode of separation were carried out and satisfactory recovery percentages (up to 99.10+/-3.12%) were obtained. The number and the h eight equivalent of the theoretical plate of the foam columns were fou nd in the range of 165 -170+/-4 and 1.85-1.93+/-0.26 mm, respectively at 10 cm(3)/min flow rate. Separation of the binary mixtures of Malath ion-Cypermethrin and Parathion-Cypermethrin insecticides from the aque ous media was achieved successfully. The helical structure of the foam sorbents offfers rapid, versatile and effective separations and preco ncentration of different compounds from fluid samples over conventiona l bulk-type granular sorbents.