Vadodariya Dharmesh M, Alwadai Norah, Abahussain Abdulaziz A M, Alrashed Maher M, Al-Yusufi Mohammed, Alreshaidan Salwa B, Alarifi Naif, Kumar Rawesh, Al-Fatesh Ahmed S
Department of Chemistry, Indus University, Ahmedabad, Gujarat, 382115, India.
Department of Physics, College of Science, Princess Nourah bint Abdulrahman University, P.O. Box 84428, Riyadh, 11671, Saudi Arabia.
Chempluschem. 2025 Jun 27:e202500228. doi: 10.1002/cplu.202500228.
Catalytic conversion of methane in the presence of O into hydrogen-rich syngas is known as partial oxidation of methane (POM). Achieving good H yield with H/CO ≈ 3 by using a low amount of Ni-based active sites at a low reaction temperature (600 °C) through POM remains challenging. Herein, magnesia-stabilized zirconia (MSZ) is prepared by the coprecipitation method by varying the amount of Mg from 8 to 14 mol%. Ni supported over MSZ catalysts are investigated for POM reaction and characterized by diffraction techniques, spectroscopic techniques, surface area-porosity, temperature-programed reduction-oxidation, and thermogravimetry. The incorporation of magnesium stabilizes both the support and the active sites. Under the oxidizing environment, the strong interaction of NiO surmounts over moderate interaction. Upon incorporation of 14 mol% Mg into ZrO (14MSZ), the catalyst attains stable support and the largest surface area, where most of the active sites are formed by "NiO under strong interaction". The catalyst surface is also enriched by Ni, Mg, and lattice oxygen. 5 wt% Ni dispersed over 14MSZ acquires the highest H yield (37%) and H/CO ≈ 3 at 600 °C and 85% H yield with ≈ 2 H/CO at 750 °C. Over 5Ni/14MSZ catalyst, the high reaction temperature restricts the indirect pathway of POM by limiting the CO yield and ensures high hydrogen yield through the direct pathways of POM.
在氧气存在下将甲烷催化转化为富含氢气的合成气被称为甲烷部分氧化（POM）。通过POM在低反应温度（600°C）下使用少量镍基活性位点实现具有H/CO≈3的良好氢气产率仍然具有挑战性。在此，通过共沉淀法制备氧化镁稳定的氧化锆（MSZ），其中镁的含量从8摩尔%变化到14摩尔%。研究了负载在MSZ催化剂上的镍用于POM反应，并通过衍射技术、光谱技术、表面积-孔隙率、程序升温还原-氧化和热重分析进行了表征。镁的掺入稳定了载体和活性位点。在氧化环境下，NiO的强相互作用超过了中等相互作用。当向ZrO中掺入14摩尔%的Mg（14MSZ）时，催化剂获得了稳定的载体和最大的表面积，其中大多数活性位点是由“强相互作用下的NiO”形成的。催化剂表面还富含Ni、Mg和晶格氧。分散在14MSZ上的5 wt% Ni在600°C时获得最高的氢气产率（37%）和H/CO≈3，在750°C时获得85%的氢气产率和≈2的H/CO。在5Ni/14MSZ催化剂上，高反应温度通过限制CO产率限制了POM的间接途径，并通过POM的直接途径确保了高氢气产率。
