PREDICTION AND VERIFICATION OF ATRAZINE ADSORPTION BY PAC

A procedure was developed to predict the removal of trace organic compounds from natural water by powdered activated carbon (PAC) adsorption systems, which function as a batch reactor or a continuous stirred tank reactor (CSTR). The procedure uses the equivalent background compound method coupled with the ideal adsorbed solution theory to quantify the competition between trace organics and background organic matter in water, and uses the pseudo single-solute homogeneous surface diffusion model to describe the adsorption kinetics of the target compound under the influence of the background organic matter. The parameters required by the model as input data can be independently determined from adsorption isotherms and a set of batch kinetic test data. Good agreement between predicted and actual performance was found for adsorption of atrazine from Central Illinois ground water at different initial concentrations and different carbon doses using a batch reactor and two CSTRs, one of which was a PAC/ultrafiltration system.