THE REMOVAL OF PESTICIDE-RESIDUES FROM WOOL WAX BY SOLVENT-EXTRACTION

A range of suitable solvents for the removal of dieldrin and diazinon residues from wool wax by solvent-solvent extraction was evaluated. Ex traction of a 10% solution of wool wax in hexane with N,N-dimethylform amide was shown to be the most effective. These solvents were then use d to measure the partition coefficients of 36 organochlorine, organoph osphorus, and pyrethroid pesticides that have the potential to be foun d in wool wax. Repeated batchwise extraction of a raw wool wax, which had been spiked to produce typical pesticide residue levels, yielded a high-quality wax in which all pesticide residues had been reduced to below detectable levels. The treated wool wax was lighter in color wit h a lowe: acid number and a lower free alcohol content and had excelle nt water absorption characteristics. All detergents associated with th e recovery of wool wax from an aqueous scour were also removed.