Comparative modelling analysis of boron dynamic adsorption on fibrous adsorbent prepared using radiation grafting versus granular resin

Abstract

A comparative study was carried to investigate the selective removal of boron from aqueous solutions over fibrous adsorbent and Diaion CRB03 granular resin in a fixed-bed dynamic column. The fibrous adsorbent was prepared by radiation induced grafting of vinylbenzyl chloride (VBC) onto nylon-6 fibres followed by treatment with N-methyl-D-glucamine (NMDG). The effect of variation of the space velocity (SV) on the breakthrough curves was investigated. The experimental boron adsorption data over both fibrous adsorbent and granular resin were analysed with various mathematical models such as Bohart-Adams, Thomas, Yoon-Nelson, Clark, and modified dose response (MDR) models using non-linear regression. The experimental adsorption data of both fibrous adsorbent and resin were found to best fit MDR model allowing the establishment of breakthrough curves. The fibrous adsorbent showed higher adsorption capacity values than granular resin at all space velocities (SV). This was accompanied by an increase in the adsorption capacity with the increase in SV from 20 to 100 h-1 unlike granular resin, which showed an opposite trend. The adsorbed boron was eluted using 0.1 M HCl and the regenerated adsorbent remained stable after adsorption/desorption 10 cycles. The results of this study suggest that the fibrous adsorbent prepared in this study outperformed the Diaion CRB03 granular resin reflecting its great potential for boron removal from aqueous solutions at pilot and industrial scaled applications.