Catalytic conversion to ammonia through solid-state nitrate as a proposal for the emerging usage of nitrogen oxides
Catalytic conversion to ammonia through solid-state nitrate as a proposal for the emerging usage of nitrogen oxides
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通过固态硝酸盐催化转化为氨作为氮氧化物新兴用途的建议
DOI：
10.1039/d3cy00169e
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发表时间：
2023
影响因子：
5
通讯作者：
Kimura Tatsuo
中科院分区：
文献类型：
--
作者：
Tomita Atsuko;Wakabayashi Ryutaro;Kimura Tatsuo
氮氧化物，NOx，是在高温下使用空气燃烧产生的有害副产品，会造成空气污染。在此，我们提出了一种催化转化系统，其通过将入口气体与含NOx的富O2燃烧气体（例如，1000 ppm NO +10%O2）到无NO/O2还原1（例如，1%H2）。根据这种气体转换操作，固态硝酸盐，存储与碱土金属物种，在环境压力下转化为气态NH3，这可能是有用的解决氮危机，以及构建一个新的工业结构的循环氮经济。介孔氧化铝颗粒内的大Pt纳米颗粒，通过气溶胶辅助的一锅法合成Pt源，然后在高温下煅烧（例如，850 °C），有助于将有效工作温度转移到更高的区域。Ba/Pt@mAl2O3（γ）型纳米复合催化剂在250 °C和更高温度下工作得非常好。对NH3的选择性达到90%，并且使用Ca/Pt@mAl2O3（γ）也实现，而没有像N2裂解的高能过程。
Nitrogen oxides, NOx, that arise anthropogenically from combustion at high temperature using air are serious byproducts that cause air pollution. Here, we propose a catalytic conversion system by alternate switching of inlet gas from NOx containing O2-rich combustion gas (e.g., 1000 ppm NO + 10% O2) to NO/O2-free reduction one (e.g., 1% H2). According to this gas-switching operation, solid-state nitrate, stored with alkali earth metal species, was converted to gaseous NH3 under ambient pressure, which would possibly be useful for solving the nitrogen crisis as well as constructing a new industrial structure of a circular nitrogen economy. Large Pt nanoparticles inside mesoporous alumina particles, created by an aerosol-assisted one-pot synthesis with Pt sources followed by calcination at high temperature (e.g., 850 °C), were helpful for shifting the efficient-working temperature to a higher region. A Ba/Pt@mAl2O3(γ) type nanocomposite catalyst worked very well at 250 °C and higher. Selectivity for NH3 reached 90%, and was also achieved using Ca/Pt@mAl2O3(γ), without a high-energy process like the cleavage of N2.