Study On Preparation Of Biomass Activated Biochar And Its Adsorption Of Tetracycline Simulated Wastewater

Antibiotics pollution to aquatic environment is becoming more and more serious withthe heavy use of antibiotics. Because of cost and removal rate, existing sewage treatmentprocess can not effectively remove the antibiotics in water. This topic used biomassgasification by-product semi-char from Jiugong mountain gasification station, TongshanCountry, Hubei province as raw material to prepare a highly active sorbent throughdeliming activation and loading zero-valent iron and some other component process. Thesorbent was used to adsorb tetracycline from water while kinetics and thermodynamicmodel were used to explain the reaction mechanism. After adsorbing saturation,microwave regeneration was used to regenerate the modified biochar. The main researchcontents and conclusions are as follows:(1) Characterization analysis methods such as industrial analysis、elementalanalysis、SEM analysis and BET analysis were used to analyze the characteristics ofmaterial biochar. The result showed that biochar was rich in carbon and oxygen. Theinterior of the biochar had abundant mesopore structure. However, a lot of pore canalswere full of ash and some pores had not yet been fully developed. The isothermaladsorption of the biochar could be described by BET adsorption equation.(2) Alkaline leaching and acid pickling were used to deliming. The ash contentcould be reduced to a lower1.95%after de-ashing; ZnCl2was used as an activator toactivate the biochar. After the activation, the specific area reached586.74m2/g; vaporphase deoxidation was used to load Fe0on biochar. The loading effect proved to be wellthrough SEM、EDX and XRD analysis. The adsorptive property of the biochar could beimproved significantly and the specific surface area could reach621.27m2/g after delimingactivation and loading Fe0.(3) Static adsorption and dynamic adsorption experiment showed that the maximumadsorption capacity of the modified biochar to antibiotics was335mg/g. Pseudo-first-order kinetics and intragranular diffusion model could fit the adsorption process perfectly.Thermodynamic analysis proved the adsorption was a spontaneous process and anendothermic reaction. Both Yoon-Nelson model and Thomas model could describe thedynamic adsorption behavior appropriately.(4) The microwave regeneration experiment indicated that the regeneration ratecould be98%and the yield of the modified biochar could be94.01%under400Wirradiation power、2minitues irradiation time and30%humidity of the regenerablebiochar.