Co改性活性炭吸附NO的实验研究

采用Co(NO_3)_2对活性炭进行改性,考察浸渍浓度和吸附温度等条件对活性炭吸附NO性能的影响,并对已吸附NO的0.3 mol·L~(-1)的Co(NO_3)_2改性活性炭进行再生。通过BET、SEM、吸附等温线和FT-IR表征样品的比表面积、颗粒形貌和表面官能团。结果表明,当浸渍溶液浓度为0.3 mol·L~(-1)时,吸附效果最佳,80 min时吸附效率达88.90%。活性炭的吸附效率随着温度升高而降低,用0.3 mol·L~(-1)Co(NO_3)_2改性的活性炭在200℃时的吸附效率大于90%,并可持续50 min。SEM和FT-IR表征结果表明,在Co(NO_3)_2改性的活性炭表面和孔隙生成了Co_3O_4,促进NO催化氧化为NO_2并进行吸附。加热再生后的0.3 mol·L~(-1)Co(NO_3)_2改性活性炭对NO的吸附效率在60 min内仍高于88.90%,再生效果较好,可持续再生利用。

NO adsorption on activated carbons modified with cobalt salt

Co(NO₃)₂ was used to modify the activated carbon and then the influence of impregnation solution concentration,adsorption temperatures on NO adsorption activity of the modified activated carbon was investigated.The activated carbon modified with 0.3 mol·L^-1 Co(NO₃)₂ after the adsorption of NO was regenerated.BET specific surface area,the particle morphology,thermal stability and functional groups of the active carbon samples were characterized by BET,SEM,NO adsorption isotherm and FT-IR.The research results showed that when the impregnating solution concentration was 0.3 mol·L^-1,the adsorption efficiency was the best and remained 88.90% for 80 min.The adsorption efficiency of activated carbon lowered with the increase of the temperature.The adsorption efficiency of activated carbon modified with 0.3 mol·L^-1 Co(NO₃)₂ remained above 90% at 200 ℃ for 50 min.According to the analysis of SEM and FT-IR,cobalt oxide was generated on the surface and in the pores of Co(NO₃)₂ modified activated carbon,accelerating catalytic oxidation from NO to NO₂ and then adsorption.After the regeneration of the activated carbon modified with 0.3 mol·L^-1 Co(NO₃)₂,the adsorption efficiency reached above 88.90% for 60 min.The modified activated carbon exhibited good regenerative effect and could make the sustainable regeneration.