Biomass materials with special wettability: a sustainable solution for efficient oil–water separation

Abstract

The increasing amount of oily wastewater is accelerating ecological damage and exacerbating water scarcity. Even though oil–water separation materials with special wettability can realize efficient treatment of oily wastewater, most of them are facing the dilemma of high cost, secondary pollution and poor biocompatibility, which greatly inhibits the sustainable development in the future. Gratefully, biomass materials with good biocompatibility, renewability and degradability are ideal for the sustainable development of oil–water separation materials. However, systematic discussions and comprehensive summaries of such environmentally friendly materials are less frequently reported in the existing literature. An in-depth discussion and a systematic summary of research progress focusing on biomass oil–water separation materials is provided in this review. First, the basic theory of wettability and the separation mechanism based on special wettability are presented. Then, the innovative progress of biomass materials in the field of oil–water separation is systematically summarized and discussed, including the design strategies, construction principles and separation mechanisms of oil-removing type, water-removing type, and Janus and smart materials. More importantly, the advantages, disadvantages and application prospects of each type of material are thoroughly analyzed and evaluated. Finally, the challenges and future development of biomass materials in the field of oil–water separation are discussed and outlined.