Yohanes Ervan and I Gede Wenten

pp. 955 - 963

Abstract

Electrodeionization (EDI), a membrane process for removing ion from aqueous feed, becomes more
popular nowadays. Its ability to produce ultrapure water gives significant contributions to chemical and
semiconductor industries. Only few researches have been published to evaluate its performance in producing ultrapure water, especially in studying and analysing the relation between process parameter and its
performance. This work is intended to observe and evaluate the influence of voltage applied and feed
concentration on EDI performance. The raw material used in experiment is tap water filtered by reverse
osmosis unit before proceeding to the electrodeionization. Product analysis, the diluate as well as the concentrate, is carried out by using conductivity meter and pH meter. The experimental results are presented in
i vs V curve, product conductivity vs time, and product pH vs time. From experimental results, it is concluded that concentration polarization can be minimized in EDI process, the increasing of applied current
increases product pH. However, there is a limit in gradient concentration between feed and concentrate to
minimize the occurence of counter diffusion phenomena