Sustainable oil-water separation and pollutant degradation with ZnO-doped wood aerogels
Taoyang Cai, Shangjie Ge‐Zhang, Hongbo Mu
Abstract
The development of the petrochemical industry necessitates the treatment of oily industrial wastewater. Addressing the separation, recovery, and reuse of oily wastewater with low-cost, high-efficiency, and environmentally friendly methods has become a significant focus in environmental protection. The search for oil-water separation materials with specific functionality and environmental durability is now a priority. In this study, natural wood was delignified, and ZnO nanoparticles were grown within the wood aerogel to create a functionalized nano-composite wood aerogel. The porous ZnO/DW aerogels exhibited an average adsorption capacity of 17.66 g g −1 . Due to the presence of a hydration shell formed by hydrogen bonding, the water-saturated ZnO/DW aerogel exhibits hydrophilic and oleophobic properties. The separation device achieved a water flux of 39,400 L m −2 h −1 and a separation efficiency of over 98.5 %, effectively facilitating oil-water separation. Furthermore, the synergistic effect of ZnO nanoparticles and wood aerogels resulted in the photocatalytic degradation of methylene blue in solution by up to 92.94 %. The cycle tests show the excellent stability of the sample in compression-release cycle, adsorption-extrusion cycle and photocatalytic degradation cycle.