ELIMINATION OF PESTICIDES FROM AQUEOUS-SO LUTION BY NANOFILTRATION

In this work the authors investigated the possibilities of elimination of two pesticides used in large amounts, and often occurring in drink ing-water sources, from water solutions with the help of nanofiltratio n. The pesticide concentrations in the samples were determined by reve rse-phase HPLC after sold-phase extraction on RP C-18 material. The de tection limit of the method was below 0.05 mu g/l. Nanofiltration expe riments were carried out in a semi-plant scale equipment. Some difficu lty was caused in the experiments by the significant adsorption of the pesticides studied in different parts of the equipment. With the memb rane used about 80 % of atrazin and about 40 % of metazachlor can be e liminated from water solutions. The efficiency of the pesticide separa tion, in contrast with the inorganic ions, was only slightly influence d by the pressure. Since the volume of the filtrate increase significa ntly with the operating pressure, the application of the greatest poss ible pressure is advisable.