Recyclable & highly porous organo-aerogel adsorbents from biowaste for organic contaminants' removal

Abstract

Selective aerogel has become an attractive adsorbent for removing oil and organic contaminants due to its low density and excellent adsorption capacity. However, aerogels usually use non-sustainable or expensive nanomaterials and require complicated fabrication processes. Herein, using low-cost lignin reclaimed from the biorefinery waste stream as the starting material, we fabricated a highly porous, mechanically strong, and stable aerogel via a simple and one-step method under mild conditions. This aerogel exhibits a controllable micropore structure and achieves quick and efficient adsorption for oil (435% g/g), as well as toxic solvents such as THF (365% g/g). The selective and stable adsorbent can be reused multiple times and the oil adsorption capacity after 5 cycles remained at 89%. This highly efficient, mechanically strong, stable, and regenerable aerogel is a potential candidate for multiple applications such as cleaning up organic contaminants, oil remediation, and oil/water separation. Meanwhile, it also employs a “waste-treat-waste” concept by adding extra value to the biorefinery process for high-efficiency circular bioeconomy.