Zeolite/slag-based porous geopolymer sphere regenerable composites with enhanced mechanical strength and good dye removal performance

Porous slag-based geopolymer spheres were synthesized by a suspension-solidification method using silicone oil as suspending bath. Zeolite powder, expected to improve or optimize the mechanical and/or adsorption properties, was used as second phase. The porous morphology, structure change, specific surface area, porosity, mechanical properties as well as adsorption capacity of the porous solid waste-based sphere composites were investigated. The mechanical strength was significantly improved by the addition of zeolite, along with a slight decrease for methylene blue adsorption properties. The obtained porous slag-based zeolite/geopolymer spheres with high porosity and acceptable strength have potential application as low cost and high effective adsorption composite materials.