改性活性炭对SO_(2)和NO_(x)的吸附性能研究

Study on the adsorption performance of modified activated carbon for SO_(2) and NO_(x)

分别采用Cu(NO_(3))_(2)、H_(2)O_(2)和KMnO_(4)对椰壳活性炭进行改性,研究了活性炭微观结构、表面化学性质变化,及其对SO_(2)、NO_(x)等酸性腐蚀性气氛的吸附性能。结果表明,Cu(NO_(3))_(2)改性活性炭比表面积显著降低,平均孔径有所下降,Cu(NO_(3))_(2)微晶分布于活性炭表面及微观孔道内,表面以碳、铜、氧和氮元素为主。H_(2)O_(2)改性活性炭比表面积有所增加,平均孔径减小,H_(2)O_(2)与活性炭表层反应后起到刻蚀效应,引入丰富的微纳孔道结构,使其表面含氧官能团增加,氧元素含量提升。KMnO_(4)改性活性炭比表面积和平均孔径略微降低,KMnO_(4)与活性炭表层反应后含氧官能团增加,反应产物附着于活性炭表面,改变其微观结构。三种方式改性的活性炭对SO_(2)和NO_(x)吸附性能均显著提升,在给定浓度下,Cu(NO_(3))_(2)改性活性炭吸附性能最优,对SO_(2)、NO_(2)和NO的吸附容量分别达到168.30、203.57和124.56mg/g。

Coconut shell activated carbon was modified by Cu(NO_(3))_(2),H_(2)O_(2) and KMnO_(4),respectively.The microstructure,surface chemical property of modified activated carbon,and its adsorption performance for SO_(2),NO_x and other acidic corrosive atmospheres were investigated.The results showed that the specific surface area of activated carbon modified by Cu(NO_(3))_(2) decreased significantly and the average pore diameter decreased slightly.Cu(NO_(3))_(2) microcrystals were distributed on the surface of activated carbon and in the microscopic pore channels,and carbon,copper,oxygen and nitrogen were predominant element on the surface.The specific surface area of activated carbon modified by H_(2)O_(2) increased slightly,however,average pore diameter decreased.The surface of activated carbon was seriously etched after the reaction with H_(2)O_(2),introducing rich micro-nano-pore structure to increase the oxygen functional groups on the surface and promote the content of oxygen element.The specific surface area and average pore diameter of activated carbon modified by KMnO_(4) decreased slightly,and the oxygen functional groups increased after the reaction between the surface layer of activated carbon and KMnO_(4).Meanwhile,the reaction products adhered to the surface of activated carbon and changed its microstructure.The adsorption performance of activated carbons modified by Cu(NO_(3))_(2),H_(2)O_(2) and KMnO_(4) for on SO_(2),NO_(2) and NO were significantly improved.The adsorption performance of activated carbon modified by Cu(NO_(3))_(2) was the optimal under the given concentration,and the adsorption capacity for SO_(2),NO_(2) and NO reached 168.30mg/g,203.57mg/g and 124.56mg/g,respectively.