Abstract

The present work is focused on the effective lifetime of reverse osmosis membranes when they are applied to the ultrapurification of aqueous hydrogen peroxide solutions, considering the very exigent purity requirements in such an oxidant medium. The comparison of commercial polyamide and cellulose acetate membranes was performed from experimental data of permeate flows and solute rejections. The obtained experimental results were adjusted to the Kedem-Katchalsky membrane transport model. The analysis of the time behavior of the membranes and the effective lifetime determination are essential in the evaluation of the economic aspects of the industrial scale installation as these properties determine the replacement rate of the membrane modules, especially for resulting extremely short effective lifetimes (only a few days). A logistic decay model was proposed for the description of the rejection coefficients of solutes as functions of the operating time. Lastly, an optimization routine was carried out to obtain optimum values for operation variables to maximize the economics of the hydrogen peroxide ultrapurification process.