Retention and separation behavior of some organophosphorus and pyrethroid insecticides on polyurethane foams

The application of polyurethane foam for the preconcentration of Cypermethrin, Malathion and Parathion insecticides was examined by the static mode of extraction. The retention of the tested species from aqueous media with the polyether polyurethane foam suggests that the solvent extraction and the cation chelation mechanism might be operative. Quantitative retention and recovery of the tested insecticides by the foam column mode of separation were carried out and satisfactory recovery percentages (up to 99.10+/-3.12%) were obtained. The number and the height equivalent of the theoretical plate of the foam columns were found 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 Malathion-Cypermethrin and Parathion-Cypermethrin insecticides from the aqueous media was achieved successfully. The helical structure of the foam sorbents offfers rapid, versatile and effective separations and preconcentration of different compounds from fluid samples over conventional bulk-type granular sorbents.