活性炭孔隙结构和表面化学性质对吸附氧化NO的影响

Effect of pore structure and surface chemical properties of activated carbon on the adsorption and oxidation of NO

采用5种粉末活性炭,在间歇式流化床实验台上研究流态化活性炭低温吸附氧化NO的动力学过程。通过N2吸附、元素分析、Boehm滴定、pH测量表征活性炭的孔隙结构和表面化学性质。结果表明:由于活性炭的原料和活化方法不同,活性炭具有不同的孔隙结构和表面化学性质,呈现不同的吸附氧化NO的动力学过程;关联稳定阶段NO氧化成NO2的转化率和活性炭性质之间的关系,发现NO的转化率与活性炭的比表面积、孔隙容积和平均孔径等参数没有明确的关系,而是随活性炭表面碱性官能团数量的增加而增加,表面化学性质是影响活性炭吸附氧化NO的主要因素。

Five kinds of powder activated carbons were investigated to the adsorption and oxidation of NO at low temperature in a batch fluidized bed reactor.The adsorbents were characterized by N2 adsorption,elemental analysis,Boehm titration and pH measurement.The activated carbons have different pore structure and surface chemical properties because of the different precursor and activation method,and present different time course of adsorption and oxidation of NO.NO conversion into NO2 in the stationary stage is correlated with the properties of activated carbons.The results show that NO conversion is independent of the pore structure such as specific surface area,pore volume,and average pore width.NO conversion increases with the amounts of surface basic functional groups.The surface chemistry is the most important factor on the adsorption and oxidation of NO for the samples used in this study.