Study On Tetracycline Adsorption Performaces Of Nitrogen And Sulfur Co-Doped Porous Carbon Materials

With the rapid development of industrial,agricultural,and medical industries,tetracycline is widely used not only for the prevention and treatment of bacterial infections but also as a growth promoter in animal husbandry.Treating tetracycline contamination in the aqueous environment is essential to maintain ecological safety.Adsorption method is an economical and high-efficiency method for the contamination removal of water bodies.The use of biomass waste as a raw material for the preparation of adsorbent not only helps to promote the resource utilization of biomass waste but also promotes the construction of national carbon peaking and carbon neutrality goals.In this paper,we have designed and prepared functional carbon materials from biomass waste from food processing,and investigated the effect of pre-oxidation temperature on the composition and structure of the carbon materials,and studied the adsorption performance and adsorption mechanism of tetracycline adsorbent.The main contents are as follows:(1)Nitrogen and sulfur co-doped porous carbon materials(BHC)were prepared from bovine horn with the help of its natural microscopic layered structure and rich in nitrogen and sulfur non-carbon heteroatoms,and the effects of different pre-oxidation temperatures on the appearance morphology and surface functional groups,etc.of BHC were investigated.It was found that the pre-oxidation treatment induced the cross-linking of keratin molecules,which would be beneficial to the inheritance of the natural structure of cow horn and the retention of nitrogen and sulfur elements during the carbonization process.The specific surface area of bovine horn biochar(BHC180)prepared by pre-oxidation treatment at 180℃was as high as 2806 m~2/g,with a total pore volume of 1.88 cm~3/g and 62.8%of micropores,providing rich adsorption sites and storage space for adsorption of tetracycline molecules in simulation wastewater.Meanwhile,the abundant heteroatoms could further enhance the chemisorption properties of BHC on tetracycline.(2)The adsorption behavior of the prepared BHC on tetracycline in simulated wastewater was investigated.The effect of p H on the adsorption of tetracycline in the simulated wastewater system was investigated,and the results showed that the neutral conditions were favorable for the adsorption of tetracycline by BHC.It was demonstrated that the Langmuir isothermal adsorption model and the pre-secondary kinetic model could better fit the isothermal adsorption and adsorption kinetics of BHC on tetracycline in the simulated wastewater system.Among them,the adsorption of tetracycline in simulated wastewater by BHC180 reached 1263.7 mg/g at 303 K.Moreover,the adsorption of tetracycline in simulated wastewater by BHC180 has a strong ability to resist the interference of other ions in the system.It was found that the adsorption capacity of BHC180 for tetracycline in simulated wastewater was mainly derived from pore filling,π-πconjugation,hydrogen bonding,and electrostatic interactions.This study provides new material for the efficient removal of tetracycline from wastewater,showing its potential for practical application.