Unraveling the reaction mechanisms of CO2 adsorption on waste paper-based porous carbon functionalized with green synthesis nitrogen-doped metal oxides

Climate change and solid waste management are two critical environmental issues. Paper waste dominates landfills. Current recycling practices face challenges such as fiber degradation, high energy usage, and water pollution. Converting waste paper, including shredded paper and corrugated cardboard into functionalized carbon materials for CO2 capture is seen as an opportunity to promote circular economy. Nitrogen doping method is an effective way to modify the surface properties of carbon materials. Conventional nitrogen doping involves the use of toxic and hazardous chemicals like amines, nitric acid, and cyanide. Exploring greener and more economical approaches is important to decrease pollution and reduce cost of operation.

This study aims to investigate the reaction mechanisms of CO2 adsorption on functionalized porous carbon using new synthesis strategy of nitrogen-doped metal oxides. The factors influencing CO2 adsorption on porous carbon surface has been investigated. Interestingly, the interaction mechanisms of CO2 molecules on functionalized porous carbon with incorporated nitrogen-doped metal oxides have not yet been addressed.

Nontoxic nitrogen sources (urea, thiourea and guanylurea) and metal oxides (limestone waste, calcium oxide) will be synthesized in microwave-assisted solvothermal process. The physicochemical properties of porous carbon will be characterized using SEM­EDS, XPS and TPD-MS analysis. A detailed study explores the interaction between nitrogen functional groups and adsorption capacity, exposing the mechanisms behind efficient CO2 capture.