Landfilled coal ash for carbon dioxide capture and its potential as a geopolymer binder for hazardous waste remediation

Preparation and CO2 Adsorption Properties of Porous Particles Based on Alkaline Solid Wastes

“…At the same time, fly ash can adjust the ratio of silicon to aluminum; silicon and aluminum dissolve into the tetrahedra of [SiO 4 ] 4– and [AlO 4 ] 5– in a strongly alkaline environment and form a three-dimensional network structure with high strength through the alternate connection of shared vertex oxygen atoms, − which enhances the strength of porous particles. Besides, fly ash, which serves as the aggregate, can increase the specific surface area and enhance the adsorption performance of porous particles. − Therefore, carbide slag and fly ash were selected as aggregates for preparing porous particles. By studying the compressive strength, CO 2 adsorption capacity, specific surface area, pore volume, and pore size distribution of the porous particles at different ratios of raw materials such as a foaming agent, alkaline activator, and surfactant, the relationship between macroscopic parameters and microstructure was analyzed to determine the best preparation method for porous particles.…”