Catalytic Methane Dehydroaromatization with Stable Nano Fe Doped on Mo/HZSM-5 Synthesized with a Simple and Environmentally Friendly Method and Clarification of a Perplexing Catalysis Mechanism Dilemma in This Field for a Period of Time

Dehydroaromatization of methane to aromatics provides a promising approach for cost-effective conversion of methane. This work was designed to study the promoting effect of nano Fe on the Mo/HZSM-5 catalyst in methane dehydroaromatization (MDA). Mo/HZSM-5 and nano-Fe modified catalysts were synthesized and then evaluated in a fixed-bed reactor along with an integrated online gas chromatography and a mass spectrometry system. The fresh or/and spent catalysts were characterized by ICP-MS, H2-TPR, CH4-TPSR, NH3-TPD, XRD, SEM, TEM, N2 adsorption/desorption, TGA, and DRIFT spectroscopy. Nano-Fe doped Mo/HZSM-5 catalysts prepared with an innovative method show enhanced MDA performances especially stability. Moreover, research demonstrates that carbon nanotubes can not only form on the Mo/HZSM-5 catalyst without the addition of Fe but also exist for a long time, which clarifies the carbon nanotubes formation mechanism. It was concluded that nano Fe plays an important role in promoting the growth of carbon nanotu...