Preparation of water insoluble carboxymethylated bacterial cellulose with maximum lead retention capacity

Abstract

Chemical modification of bacterial cellulose (BC) through carboxymethylation was carried out to prepare a low-cost highly stable lead adsorbent material (CMBC). Aiming to maximize its adsorption capacity, the effect of the carboxymethylation extent conferred to BC on the lead retention ability of the insoluble CMBC products obtained was studied. Results evidenced a strong linear correlation between the lead retention capacity of CMBC samples and their degree of substitution, highlighting a key role on the biobased adsorbents performance of the amount of negatively charged carboxylate groups available for an ion-exchange-governed lead adsorption process. Proper tuning of the carboxymethylation extent conferred to BC thus allowed maximizing its lead adsorption capacity, reaching values (i.e. 127.2 mg g−1) that doubled those previously reported.