Thiourea bacterial cellulose imprinted aerogel construction by oriented assembly for selective adsorption of Er(III) from rare earth leachate

Abstract

The selective recovery of Er(III) from the leachate is of environmental and economic importance based on the non-renewability and strategic position of high-value heavy rare earth elements. In this study, functionalize bacterial cellulose (BC) with unique three-dimensional network structure was used as the oriented imprinting framework for construction of thiourea BC imprinted aerogel (DBCT-IIPS). The oriented assembly process allows all the imprinted sites to be located on the surface of the BC, which greatly improves the mass transfer efficiency compared to the conventional imprinting process. Experimental analysis shows that functional modification of BC and the crosslinking of hydrazine group greatly improve the stability and adsorption properties of aerogel materials. Adsorption experiments showed that DBCT-IIPS can fast and selectively adsorb Er(III) from rare earth leachate. The maximum adsorption capacity reaches 65.43 mg g−1. After 5 times of adsorption and desorption, adsorption capacity of DBCT-IIPS can still maintain 81.6% of the initial capacity. So, DBCT-IIPS can efficiently and selectively recover of Er(III) from rare earth leachate.