Cu-supported alkali activated carbon as a green catalyst for organic conversion and environmental remediation

Green, eco-friendly approaches to designing high-performance catalysts offer a potential solution for environmental remediation, enabling the production of value-adding products and enhancing environmental sustainability. In this study, a green-synthesized Cu-supported active carbon was prepared via a wet impregnation technique. Activated carbon derived from date pits was impregnated with a copper acetate solution at different loadings of 5% for Cu-AS1, 10% for Cu-AS2 and 15% for Cu-AS3. The kinetics of catalytic conversion of hydrocarbon over Cu-supported activated carbon from date pits were studied at 280-380 °C and contact times of 13.63-6.52 min in a flow system under normal pressure. TGA, DTA, X-ray, and BET surface area measurements were used to characterize the treated prepared samples. The liquid and gaseous reaction products were analyzed using gas-liquid chromatography (GLC) to evaluate the catalytic activity and selectivity toward benzene formation. Furthermore, the treated samples were evaluated for their environmental remediation activity in removing various heavy metal ions such as Co²⁺, Ni²⁺, Fe³⁺, and Cd²⁺ ions. The results revealed that, benzene was identified as the predominant product under the investigated reaction conditions, whereas toluene and xylene were formed via alkylation. The apparent activation energies were 11.05 kcal mol^-1 for Cu-AS1, 10.51 kcal mol^-1 for Cu-AS2 and 9.75 kcal mol^-1 for Cu-AS3; these values are maybe affected by mass-transfer effects. Conversion (%) increased with temperature and the formation rates of gaseous products (H₂, CH₄, C₂H₆), indicating enhanced catalytic performance due to higher copper dispersion and improved pore accessibility. The treated samples effectively removed Co²⁺, Ni²⁺, Fe³⁺, and Cd²⁺ ions at concentrations of 10-30 mg L^-1, with adsorption fitting Langmuir and Freundlich models (R _L < 1 and n > 1), indicating favorable and efficient adsorption behavior.