Study on the Adsorption Properties of Graphene Oxide/Porous SiO₂ Microsphere Composites

A large amount of protein residues are produced during the processing of raw materials in leather industry. The separation and recovery of these residues from tannery wastewater by using adsorbents can realize the recycling use of leather wastewater pollutants. Herein, graphene oxide/porous SiO₂ microsphere composites (GO/C-PSM) were synthesized by using fish skin collagen as raw material template with the addition of GO powder. Protease, lysozyme (LZ), was used as the theoretical research object. Results showed that the maximum adsorption capacity of GO/C-PSM for LZ was 45.4 mg/g, and the adsorption process was consistent with the pseudo-second-order adsorption kinetics model. At the same time, the adsorption isotherm model of GO/C-PSM for LZ conformed to the Langmuir isotherm model. After five cycles, the adsorption rate of GO/C-PSM still reached more than 80%. In addition, GO/C-PSM also had a certain adsorption and separation effect for proteins in actual tannery wastewater.