Comprehensive Study on Amino-Modified Salix Wood Powder Membranes: Preparation, Adsorption Mechanism and Desorption Conditions for Efficient Chlortetracycline Removal

Abstract

The wastewater of Chlortetracycline (CTC) poses a threat to the balance of aquatic ecosystems, promoting the formation and dissemination of antibiotic-resistant bacterial strains in the aquatic environment. Moreover, such pollution can directly or indirectly affect human health through water sources, exacerbating the issue of antibiotic resistance. In response to this pollution challenge, Amino-modified salix wood powder membrane(ASPPM) was prepared by phase transition and wet spinning techniques, aimed at removing CTC from water bodies. Adsorption experiment results show that the ASPPM maximum adsorption capacity for CTC is 459 mg/g. In the desorption process, the highest desorption rate of ASPPM for CTC was 79.65 %. By fitting pseudo-first-order and pseudo-second-order kinetic models, it is found that the adsorption process of ASPPM on CTC is predominantly chemical adsorption. By fitting three isotherm models, it is found that the adsorption behavior of ASPPM on CTC is more in accordance with the Freundlich isotherm model, indicating multilayer adsorption on heterogeneous surfaces. Thermodynamic analysis indicates that the adsorption process of ASPPM on CTC is spontaneous, exothermic and accompanied by an increase in entropy at different temperatures. Furthermore, ASPPM has a highly porous structure. During its preparation, the characteristic absorption peaks of −CONH and −NH₂ in ASPP are preserved and the cellulose type I in ASPPM is transformed into type II, resulting in a more orderly crystal structure. The preparation of ASPPM study not only transforms renewable biomass materials into effective tools for environmental purification but also offers a cost-effective new approach for sustainable environmental management, expanding the application of biomass materials in the field of environmental protection.