(519d) Three-Dimensional Lignin-Based Smart Aerogel for Controllable Oil/Water Separation

Jingxian Jiang, Qinghua Zhang, Xiaoli Zhan, Fengqiu Chen

College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, P. R. China

ABSTRACT

Recent years, oil/water separation has become a worldwide challenge. Among all these approaches to deal with this severe problem, adsorption separation shows promising prospects due to its high efficiency, easy manipulation, and practicability under harsh circumstances. Oil sorbents derived from biomass which is a kind of available renewable resource, also have the advantages of cost-effectiveness, environmental-friendliness and convenient enrichment of multi-functionality. Herein, we present a facile method to fabricate a self-standing compressible three-dimensional lignin-based aerogel with porous structure, low density and a smart surface that can be responsive to medium pH. Based on the hydrolytic condensation effect of silane coupling agent, the copolymer P(DMAEMA-SA-KH570) synthesized by free radical polymerization was covalently bonded onto the lignin-based aerogel through simple dip-coating method. The integrated aerogel exhibited superhydrophobic and superoleophilic properties and could be served as effective oil sorbent when medium pH was 7 with an adsorption capacity for oil and organic solvents of 20-40 times of its own weight. And it could realize oil desorption when medium pH was changed to 1. Furthermore, the cycling stability of aerogel was evaluated by both mechanical squeezing and pH controlling. This work presents a method to fabricate robust smart oil-absorbing aerogel for controllable oil/water separation based on lignin and offers a new viable sustainable approach for oil recovery.