Diffusion dialysis for separating acidic HCl/glyphosate liquor

摘要

Acidic HCl/glyphosate liquor is produced largely during the production of glyphosate herbicide, which contains 2.5-3.0 mol L-1 HCl, 1.1-1.5 mol L-1 glyphosate and 34-35 wt% other organic components. The acidic liquor is traditionally neutralized to pH 1.5 by alkali (NaOH) for the maximum crystallinity of glyphosate. Here the acidic liquor is separated by commercial anion exchange membrane 9010 through batch diffusion dialysis (DD). The DD process shows the advantages including recovery of HCl, crystallization of glyphosate, and low dosage or avoidance of alkali. The DD performances are evaluated by acid concentration, dialysis coefficients of HCl (U-H) and separation factor (S) with respect to the time.