Effect of surface oxygen/nitrogen groups on hydrogen chloride removal using modified viscose-based activated carbon fibers
Effect of surface oxygen/nitrogen groups on hydrogen chloride removal using modified viscose-based activated carbon fibers
复制标题
表面氧/氮基团对改性粘胶基活性炭纤维去除氯化氢的影响
DOI：
10.1039/c5ra11705d
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发表时间：
2015
期刊：
影响因子：
3.9
通讯作者：
Qiu Jianrong
中科院分区：
文献类型：
--
作者：
Wang Zean;Liu Hao;Zhou Kang;Fu Peifang;Zeng Hancai;Qiu Jianrong
活性炭纤维（ACFs）具有丰富的微孔和较大的比表面积，可以有效去除氮氧化物、硫氧化物和微量金属等污染物。这项工作旨在研究表面碳氧和氮氧在使用粘基ACFs去除氯化氢（HCl）中的作用。为了评价表面碳氧基团和氮氧基团对商品粘基ACFs的影响，采用热处理（900℃）和化学浸渍（H2O2、HNO3和Cu(NO3)2）处理。孔隙体积、平均孔径和比表面积分别采用t-plot法、密度泛函理论和brunauer - emmet - teller理论进行表征。用扫描电镜观察了活性炭纤维的表面形貌。采用x射线光电子能谱（XPS）技术测定了表面氧和氮基团的比。采用程序升温解吸法研究了ACFs对HCl的吸附行为。实验结果表明，热处理降低了碳氧基团，而H2O2浸渍增加了碳氧基团（尤其是羰基和羧基）。HNO3和Cu(NO3)2处理后，碳表面引入亚硝基和硝基。由于碳氧基团的增加，H2O2处理对HCl的去除率略有提高，HNO3和Cu(NO3)2处理对HCl的去除率有显著提高，因为新形成的氮氧基团。亚硝基和硝基对ACFs表面的HCl保留能力有显著的促进作用。亚硝基对HCl去除率的影响大于硝基对HCl去除率的影响。
Activated carbon fibers (ACFs) can effectively remove pollutants including nitrogen oxides, sulfur oxides and trace metals due to their rich micropores and large specific surface area. This work aims to investigate the roles of surface carbon–oxygen and nitrogen–oxygen species on the removal of hydrogen chloride (HCl) using viscose-based ACFs. To evaluate the effect of surface carbon–oxygen and nitrogen–oxygen groups, commercial viscose-based ACFs were treated by thermal treatment (900 °C) and chemical impregnation using H2O2, HNO3 and Cu(NO3)2. Pore volumes, average pore sizes and specific surface areas were separately characterized by t-plot method, density functional theory and Brunauer–Emmett–Teller theory. The surface morphology of the ACFs was observed by a scanning electron microscope. An X-ray photoelectron spectroscopy (XPS) technique was applied to determine the specific ratios of surface oxygen and nitrogen groups. Temperature programmed desorption was performed to investigate HCl adsorption behaviors over the ACFs. As experimental results, the thermal process decreased the carbon–oxygen groups while H2O2 impregnation increased the carbon–oxygen groups (especially carbonyl and carboxyl). Nitroso and nitro groups were introduced onto the carbon surface after HNO3 and Cu(NO3)2 treatments. The removal efficiency of HCl was improved slightly by H2O2 modification due to the increase of carbon–oxygen groups, and significantly by HNO3 and Cu(NO3)2 treatments because of newly formed nitrogen–oxygen groups. Nitroso and nitro groups show significant promotion of HCl retention ability over the ACFs surface. Moreover, HCl removal efficiency was much more influenced by nitroso than nitro groups.