Zhang Jie, Li Xiangcheng, Chen Pingan, Zhu Boquan
The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081, China.
Materials (Basel). 2018 Sep 6;11(9):1632. doi: 10.3390/ma11091632.
Selective catalytic reduction of NO with NH₃ is one of the most widely used technologies in denitration. Vanadium-based catalysts have been extensively studied for the deNO process. V₂O₅/WO₃(MoO₃)TiO₂ as a commercial catalyst has excellent catalytic activity in the medium temperature range. However, it has usually faced several problems in practical industrial applications, including narrow windows of operation temperatures, and the deactivation of catalysts. The modification of vanadium-based catalysts will be the focus in future research. In this paper, the chemical composition of vanadium-based catalysts, catalytic mechanism, the broadening of the temperature range, and the improvement of erosion resistance are reviewed. Furthermore, the effects of four major systems of copper, iron, cerium and manganese on the modification of vanadium-based catalysts are introduced and analyzed. It is worth noting that the addition of modified elements as promoters has greatly improved the catalytic performance. They can enhance the surface acidity, which leads to the increasing adsorption capacity of NH₃. Surface defects and oxygen vacancies have also been increased, resulting in more active sites. Finally, the future development of vanadium-based catalysts for denitration is prospected. It is indicated that the main purpose for the research of vanadium-based modification will help to obtain safe, environmentally friendly, efficient, and economical catalysts.
氨选择性催化还原NO是脱硝领域应用最为广泛的技术之一。钒基催化剂在脱硝过程中得到了广泛研究。V₂O₅/WO₃（MoO₃）TiO₂作为一种商业催化剂，在中温范围内具有优异的催化活性。然而，它在实际工业应用中通常面临几个问题，包括操作温度窗口狭窄以及催化剂失活。钒基催化剂的改性将是未来研究的重点。本文综述了钒基催化剂的化学组成、催化机理、拓宽温度范围以及提高抗侵蚀性等方面。此外，还介绍并分析了铜、铁、铈和锰四大体系对钒基催化剂改性的影响。值得注意的是，添加改性元素作为促进剂极大地提高了催化性能。它们可以增强表面酸度，从而导致NH₃吸附容量增加。表面缺陷和氧空位也有所增加，从而产生更多活性位点。最后，对钒基脱硝催化剂的未来发展进行了展望。结果表明，钒基改性研究的主要目的将有助于获得安全、环保、高效且经济的催化剂。
