In view of the serious environmental pollution, which is the greatest problem the world is facing, and the continuous consumption of raw materials, it is imminent to search for green and sustainable resources. Lignin is an organic polymer that exists widely in nature, and if it can be transformed from traditional low-value waste product with low range of applications to functional materials with high application prospects, it can be of great significance to alleviate environmental pollution and shortage of fossil resources. One of the functional applications of lignin involves its use to fabricate composite with other polymeric materials, which can then be used to prepare membrane materials. This review summarizes the recent research and application progress of combining lignin with polypropylene, polyvinyl alcohol, starch, cellulose, chitosan, and other polymeric materials to prepare composite membranes; and summarizes the future development direction of lignin-based composite membranes. We hope this review may provide a new perspective to the understanding of lignin-based composite membranes and a useful reference for future research.

The present study deals with the synthesis of zeolite-loaded FeOOH@ZnO by hydrothermal method and investigates the effects of coexisting SO32− and PO43− ions in the aqueous solution on the adsorption performance for S2−. The results showed that the HNO3-modified zeolite loaded with FeOOH@ZnO (FeOOH@ZnO/HZ) resulted in a maximum S2− removal rate of ≈98%. The adsorbent's performance on removing S2− was significantly enhanced, compared with NaOH and ZnCl2-modified zeolites loaded with FeOOH@ZnO, and the adsorption was proved to be a heat-absorbing process. When SO32− and PO43− coexisted with S2−, SO32− and PO43− had a significant influence on the adsorption properties of FeOOH@ZnO/HZ. When three ions of S2−, SO32− and PO43− were present simultaneously, the adsorption performance of FeOOH@ZnO/HZ on S2− was further, and the removal rate dropped to about 80%. Moreover, FeOOH@ZnO/HZ also adsorbed PO43− and SO32− in the system containing multiple ions, but the adsorption rates of PO43− and SO32− were much lower than S2−. This indicated that the adsorption of S2− in the presence of FeOOH@ZnO/HZ dominates under competitive conditions.

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