FACTORS AFFECTING SORPTION OF PENTACHLOROPHENOL TO SUSPENDED MICROBIAL BIOMASS

Sorption and desorption of pentachlorophenol (PCP) to microbial biomas s was studied in a series of laboratory experiments. Equilibrium condi tions for sorption and desorption were established within 5 min after a step change in concentrations. Linear sorption isotherms were observ ed at up to 80 mu g/l of dissolved PCP at pH 6, and up to 160 mu g/l a t pH 8. Linear sorption coefficients were primarily influenced by pH, although ionic strength (owing to pH-buffering) and the concentration of dissolved organic matter also had an impact. The influence of these factors was quantified by a simple mathematical model, which included separate sorption coefficients for the neutral and dissociated fracti on of PCP.