锰活性物质负载Ti掺杂SiO2纳米管复合催化剂的制备及其NH3-SCR反应活性 |
Preparation of Titania Doped SiO2 Nanotube Composites with Manganese Loadings for NH3-SCR Applications |
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摘要: 利用溶胶-凝胶法以及共缩聚反应合成得到了新型的Ti掺杂SiO2纳米管(TiSNTs)。然后,利用共沉淀的方法在该催化剂上负载了不同Mn含量的Mn/TiSNTs复合催化剂。当Si与Ti的物质的量之比超过5时,可以看到形成了很清楚的蠕虫状形貌。NH3-TPD(氨气程序升温脱附)测试结果显示掺杂到SiO2骨架中的Ti极大增强了催化剂的酸性位点而且提高了NH3在催化剂表面的吸附量和氨选择性催化还原(NH3-SCR)的活性。同时,H2-TPR(氢气程序升温还原)测试结果显示Ti掺杂增强了催化剂的氧化还原能力和储氧容量。NH3还原NOx的SCR结果说明当Si与Ti的物质的量之比为10的时候,Mn/Ti(10)SNT催化剂显示了优异的催化活性,在温度范围为135~325℃时NO转化率超过90%。 |
关键词: 异相催化 负载型催化剂 二氧化硅 纳米管 溶胶-凝胶过程 |
基金项目: 国家自然科学基金(No.21571024,21101017/B0107),江苏省自然科学基金(No.BK20181056),江苏省普通高校研究生科研创新计划(No.SJZZ15_0142)和配位化学国家重点实验室开发课题(No.SKLCC1802)资助。 |
Abstract: Ti-containing SiO2 nanotubes (TiSNTs) were firstly synthesized via a sol-gel and co-polycondensation method. After that, a family of Mn doped TiSNTs (Mn/TiSNTs) catalysts with various Mn loading were prepared via the co-precipitation method. When Si/Ti molar ratio was more than 5, a worm-like tubular morphology was clearly observed. The NH3-TPD (NH3-temperature programmed desorption) results show that the Ti doping into the skeleton of the silica nanotubes greatly enhanced the acidic sites of the catalyst and promoted the adsorption and NH3-SCR (selective catalytic reduction) activation on the surface of the catalyst. Meanwhile, the results of H2-TPR (H2-temperature programmed reduction) also show that Ti doping enhanced the redox ability of the catalyst and the capacity of oxygen storage. Moreover, the doped Mn species was beneficial for reducing the reaction temperature. The results of SCR of NOx with NH3 show the catalyst with Si/Ti molar ratios of 10 (Mn/Ti(10)SNT) exhibited significant catalytic activity, and the NO conversion rate remained over 90% in the reactive temperature range of 135 to 325℃. |
Keywords: heterogeneous catalysis supported catalysts silicates nanotubes sol-gel processes |
投稿时间:2018-07-08 修订日期:2018-09-11 |
摘要点击次数: 1909 |
全文下载次数: 1202 |
叶永洲,沈飞,王红宁,陈若愚,孙林.锰活性物质负载Ti掺杂SiO2纳米管复合催化剂的制备及其NH3-SCR反应活性[J].无机化学学报,2018,34(11):2088-2096. |
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