Removal of dimethylarsinate from water by robust NU-1000 aerogels: Impact of the aerogel materials

Abstract

This study compared the effect of three matrices on the dimethylarsinate (DMA) removal from water to NU-1000 (zirconium-based metal–organic framework, Zr-MOF) hybrid aerogels. The porous MOF hybrid aerogels were prepared by grafting NU-1000 into green matrices, i.e., agarose (AG), sodium alginate (SA), and carboxymethyl cellulose (CMC) sodium salt. The adsorption data of DMA can be well described by the pseudo-second-order kinetic model and the Freundlich isotherm model. The maximum adsorption capacity of the NU-1000@AG hybrid aerogel for DMA (119.63 mg/g) was higher than the other two hybrid aerogels due to the negligible interference of AG on the active adsorption sites in NU-1000. However, the functional groups in NU-1000@CMC hybrid aerogel and NU-1000@SA hybrid aerogel occupied the Zr adsorption sites during the cross-linked process and decreased their adsorption capacities. The NU-1000@AG hybrid aerogel demonstrated application potential for removing DMA in a fixed-column dynamic adsorption process. Furthermore, the NU-1000 hybrid aerogels exhibited excellent regeneration performance and ease of solid–liquid separation. The characteristics of various matrices may offer diversified facile and viable strategies for fabricating a blocky adsorbent with superior stability and solid–liquid separation efficiency for water treatment, overcoming the disadvantages of MOF powder and ensuring maximum effectiveness of adsorbent components.