Extraction of glyphosate by a supported liquid membrane technique

The possible application of the supported liquid membrane (SLM) technique f or the extraction of glyphosate is presented. For the extraction of this co mpound the SLM system has been applied with utilisation of Aliquat 336 as a cationic carrier incorporated into the membrane phase. The extraction effi ciency of glyphosate [N-(phosphonomethyl)glycine] is dependent on the donor phase pH, carrier concentration in the organic phase and NaCl concentratio n in the acceptor phase. The optimal extraction conditions are: donor phase pH>11, acceptor phase of 2 M NaCl solution and the organic phase composed of 20% (w/w) Aliquot 336 solution in di-hexyl ether. Counter-coupled transp ort of chloride anions from the acceptor phase to the donor phase is a driv ing force of the mass transfer in this system. (C) 2000 Elsevier Science B. V. All rights reserved.