Investigation Of Preparation,Modification And Peformace Of A Activated Carbon From Thalia Dealbat

A Low-cost and effective activated carbon was prepared from Thalia dealbata by phosphoric acid activation. Its ability to remove the antibiotics, and heavy metals were evaluated. The effects of experimental parameters such as pH, ionic strength, initial concentration, contact time and temperature on the adsorption were investigated. The adsorption kinetics and thermodynamics were also discussed. Microwave-assitant regeneration studies were examined in further elucidating the mechanism of adsorption and the feasibility of regenerating the spent activated carbon.The preparation condition of TLAC was at a H3PO4concentration of40%, an impregnation ratio of2:1, an impregnation time of20min, an activated temperature of500℃and an activated time of1h. The adsorbent appeared to have a coarse porous surface with irregular pores and is an amorphous structure. The surface area of TLAC was found to be938.28m2/g. There were many founctional groups on the surface such as:carboxylic, phenolic, lactonic and carbonnylic, acidic groups were more than basic ones and carboxylic was the main group. And the results showed that TLAC has a high capacity for streptomycin and Pb(II),170and68mg/g.Modification by sodium thiosulphate changed the surface area and element portion of TLAC, and promoted its adsorption ability. Compared with TLAC, the adsorption capacity of TLAC-ST was very high240and130mg/g. The adsorption on TLAC-ST was highly pH dependent and the removal efficiency of streptomycin was increased with increasion in initial pH, while the TLAC was not. The adsorption kinetics was found to be best represented by the pseudo-second-order kinetic model. The mechanism of the adsorption process was determined from the intraparticle diffusion model. The equilibrium adsorption data was well described by the Langmuir model. Thermodynamic study showed that the adsorption was a spontaneous process. It was an endothermic process for streptomycin. And the result indicated that microwave-asistant regeneration is an effective way to restore the adsorption capacity ofTLAC.