Tourmaline-Modified FeMnTiO _x Catalysts for Improved Low-Temperature NH₃-SCR Performance

Low temperature NH₃ selective catalytic reduction (NH₃-SCR) technology is an efficient and economical strategy for cutting NO _x emissions from power-generating equipment. In this study, a novel and highly efficient NH₃-SCR catalyst, tourmaline-modified FeMnTiO _x is presented, which was synthesized by a simple one-step sol-gel method. We found that the amount of tourmaline has an important impact on the catalytic performance of the modified FeMnTiO _x-based catalysts, and the NO _x conversion exceeded 80% from 160 to 380 °C with the addition of 5 wt % tourmaline. Compared with the pure FeMnTiO _x, the catalytic efficiency at a temperature below 100 °C was increased by nearly 18.9%, and the operation temperature window was broadened significantly. The enhanced catalytic performance of the FeMnTiO _x catalyst was mainly attributed to the small spherical nanoparticles structure around the tourmaline powders, resulting in the increased content of Mn³⁺, Mn⁴⁺, and chemical oxygen on the catalytic surface. These as-developed tourmaline-modified FeMnTiO _x materials have been demonstrated to be promising as a new type highly efficient low temperature NH₃-SCR catalyst.