Ferric Salt Modified Sludge-stalk Based Activated Carbon And Removal Of H₂S

The resource utilization of sludge and corn stalk has become the hotspot of research.The preliminary results of my research group show that mixed the two kinds of waste and prepared the activated carbon by high temperature pyrolysis under inert conditions.The activated carbon has good adsorption capacity of H2 S.In order to enhance the desulfurization effect of activated carbon,the sludge-stalk based activated carbon was modified with ferric nitrate,ferric chloride and ferric sulfate.Then orthogonal experiment was utilized to investigate the optimum conditions for the preparation of activated carbon.Combined with analysis methods such as BET specific surface area and pore size experiment,XRD,FT-IR,TGA-DSC,XRF and XPS to characterize the activated carbon.The effect of temperature on the desulfurization performance of activated carbon was studied,and the regeneration conditions of activated carbon were preliminarily studied.The main research contents and conclusions are as follows:(1)The BET specific surface area of sludge-stalk based activated carbon was 462.931m2/g,which was rich in microporous structure.In three kinds of ferric salt modifier,the activated carbon modified by ferric nitrate has the best desulfurization effect and its breakthrough sulfur capacity and saturated sulfur capacity reached 12.891mg/g and 15.690mg/g which were 2.13 times and 2.11 times compared to unmodified activated carbon.(2)The orthogonal experiment of activated carbon modified by ferric nitrate s howed that the best conditions were as follows: calcination temperature 200?,imp-regnation ratio 1:4,calcination time 1.5h,concentration of ferric nitrate 1.0mol/L.Orthogonal experimental's analysis of variance showed that the calcination temperat-ure had a significant effect on the breakthrough sulfur capacity of activated carbon which modified by ferric nitrate.(3)The alkaline environment on the surface of activated carbon is beneficial to its adsorption of hydrogen sulphide.The activated carbon's adsorption of hydrogen sulphide at different temperatures showed that activated carbon has the best desulfurization effect at 50?.(4)The characterization of activated carbon showed that Fe2O3 was introduced into the surface of activated carbon when modified by ferric nitrate,but Fe2O3 only catalyzed the process of adsorbing hydrogen sulfide on the activated carbon.The reaction of activated carbon's adsorption of hydrogen sulfide mainly occurred in microporous structure.(5)The study on desulfurization performance of activated carbon after regeneration showed the effect of first regeneration of hydrogen peroxide is better than the thermal regeneration method.The breakthrough sulfur capacity and saturated sulfur capacity of activated carbon,which regenerated by hydrogen peroxide,can be restored to more than 66%.