Recent advances in flat sheet mixed matrix membrane modified by Mg-based layered double hydroxides (LDHs) for salt and organic compound separations

Abstract

Magnesium (Mg) is a widely used and attractive metal, known for its unique physical and chemical properties, and it has been employed in the manufacture of many practical materials. Layered Double Hydroxides (LDHs), particularly Mg-based LDHs, rank among the most prevalent two-dimensional materials utilized in separation processes, which include adsorption, extraction, and membrane technology. The high popularity of Mg-based LDHs in separation applications can be attributed to their properties, such as excellent hydrophilicity, high surface area, ion exchangeability, and adjustable interlayer space. Currently, polymer membranes play a pivotal role in semi-industrial and industrial separation processes. Consequently, the development of polymer membranes and the mitigation of their limitations have emerged as compelling topics for researchers. Several methods exist to enhance the separation performance and anti-fouling properties of polymer membranes. Among these, incorporating additives into the membrane polymer matrix stands out as a cost-effective, straightforward, readily available, and efficient approach. The use of Mg-based LDHs, either in combination with other materials or as a standalone additive in the polymer membrane matrix, represents a promising strategy to bolster the separation and anti-fouling efficacy of flat sheet mixed matrix polymer membranes. This review highlights Mg-based LDHs as high-potential additives designed to refine flat sheet mixed matrix polymer membranes for applications in wastewater treatment and brackish water desalination.