Natural zeolite is a hydrated aluminosilicate substance that has excellent ion exchange and adsorption properties and is environmentally and economically friendly. This review describes the current application and modification of zeolite in wastewater treatment using acid and surfactants, zeolite composites (such as zeolite membranes), permeable reactive barriers and photocatalysts. The properties of zeolite as well as the regeneration and desorption of cast-off zeolite are briefly reviewed. Modifications are made to improve the capability of zeolite in wastewater treatment facilities. Furthermore, this review proposes the integration of zeolite and other available technologies to treat emerging pollutants in wastewater. Different types of zeolite (natural and synthetic zeolite of different origins) are compared, and their properties are evaluated. Different type of pollutants and treatment methods involving zeolite are also discussed. Zeolite is enhanced to solve the problem of various pollutants in wastewater.

Carbon membranes are known for their high performance in the separation of gases, particularly for gases with similar kinetic diameter. For this reason, the investigation of carbon membranes continues to increase their performance by tweaking the formulation and heating strategy. One of the formulation aspects is polymer selection, which plays an important role in determining the success of producing carbon membrane with acceptable performance. This is because each polymer has its own characteristics, which then determines the method to be used to synthesize the carbon membrane. Four types of polymers were identified to produce carbon membranes, which are based on non-modified polymer solutions, modified polymer or polymer solutions, non-commercial organic materials and natural polymers such as natural cellulose. This review discusses the overview performances provided by each material.