Removal of heavy metal cations using mesoporous silicagel modified with L-cysteine

Mesoporous SiO₂ was synthesized via sol-gel technology under acidic conditions at 50°C. The surface of the obtained sorbents was modified with the amino acid L-cysteine, and their textural characteristics were investigated. After modification with L-cysteine, the specific surface area increased to 975.6 m²/g, and the nitrogen adsorption capacity reached 7.3 mol/kg. The adsorption of Cu²⁺ and Pb²⁺ cations on the sorbents was also studied.