Preparation Of Multicomponent Modified Ferric Oxide And Study On Its Desulfurization And Regeneration Performance

Hydrogen sulfide gas is one of main odorous gases emitted during industrial production.The research object of this paper is H₂S gas.A multicomponent modified Fe₂O₃ composite desulfurizer was prepared by co-precipitation method.The desulfurization and regeneration properties of Fe₂O₃ modified by different elements?Cu,Zn,Al,Ce and La?were investigated in a self-designed experimental system,The specific surface area and pore structure of BET DTA-TG,XRD and TEM were also investigated,The results show that:1)CuO-Fe₂O₃,ZnO-Fe₂O₃,Al₂O₃-Fe₂O₃,CeO₂-Fe₂O₃ and LaO₂-Fe₂O₃ were prepared by co-precipitation method in the oxidizing atmosphere.The results showed that when the H₂S concentration was 3000 mg?m^-3,the heating temperature was 25-40?,the space velocity was 4200h^-1,the best effect of desulphurization was Al₂O₃-Fe₂O₃,and the sulfur content was 8.80%.The poor desulfurization effect was ZnO-Fe₂O₃,and the sulfur capacity was 5.31%.The optimum preparation conditions of Al₂O₃-Fe₂O₃ were as follows:co-precipitation reaction temperature 40?,curing 24h,calcination temperature 500?,roasting time 3h,Al₂O₃ additive content 20%.2)Preparation of LaO₂-Al₂O₃-Fe₂O₃ desulfurizer by co-precipitation method in oxidizing atmosphere.The results show that the optimum roasting temperature was 500?,the roasting time was 3h,the content of LaO₂-Al₂O₃-Fe₂O₃ component was LaO₂,4%,Al₂O₃,20%,Fe₂O₃,76%,the desulfurization effect was best,and the sulfur content was9.3%.3)Using XRD,TEM and BET specific surface area pore structure to characterize Al₂O₃-Fe₂O₃ and LaO₂-Fe₂O₃desulfurizer,the results show that:a large number of alpha-Fe₂O₃ occurs at 500 degrees of roasting,and the iron element exists in the form of Fe³⁺.Al₂O₃-Fe₂O₃ samples with small particle size,uniform distribution,the maximum specific surface area,improve the activity and reaction with H₂S physical adsorption;LaO₂ can accelerate the reaction speed of LaO₂-Fe₂O₃ and H₂S,shorting the reaction time,it relatively increase in air speed;therefore Al₂O₃ and LaO₂ can promote the desulfurization performance of Fe₂O₃ in different aspects.4)The regeneration effect and pore structure of three kinds of desulfurizer,Al₂O₃-Fe₂O₃,LaO₂-Fe₂O₃ and LaO₂-Al₂O₃-Fe₂O₃,were studied.Three kinds of sorbent regeneration at room temperature,due to blockage of S elements lead to relatively lower than the surface area and pore volume;For high temperature regeneration,LaO₂-Fe₂O₃regeneration temperature is higher,and the specific surface area and pore volume decreased seriously,it is not conducive to recycling,Al₂O₃-Fe₂O₃ and LaO₂-Al₂O₃-Fe₂O₃at relatively low temperature can be regenerated,the regeneration after the surface area and pore structure change is small,Al₂O₃-Fe₂O₃ and LaO₂-Al₂O₃-Fe₂O₃ total sulfur content are 31.6%,38.9%,when the regeneration temperature is 400?,the regeneration rates are 92.3%and 94.3%.