Desalination and adsorption in an electrodialysis process.

摘要

The objectives of this study are to evaluate the combined effects of separation properties of electrodialysis and adsorption to simultaneously remove organic compound and ionic species. Studies of individual processes and combinations were conducted to consider their responses. The effect of graphite as adsorbent on the electrodialysis performance was examined. Also, membrane transport properties were analyzed in a presence of 2-naphthol (;The results shoved that graphite may prolong service life of the ion-selective membranes that are essential in separation. Adsorption predominated 2-naphthol removal; otherwise, 2-naphthol likely fouled the membranes. The supplied potential had no effect on the graphite adsorption. In addition, affinity of 2-naphthol onto the membranes altered the permeability and transport properties of the membranes. The ionic separation efficiency of the electrodialysis cell was, however, reduced by 2-naphthol and graphite.;A process model was developed to predict the removal performance. Besides the electrical phenomenon, the model also incorporates the graphite adsorption and the membrane sorption. The model agreed well with the experimental data within the 90 percent confidence level. From the sensitivity analysis, permselectivity of membranes, specific conductivities of membranes and graphite, cell thickness, and the applied potential were significant parameters for the model.