Oxidative Dehydrogenation of Propane (ODHP) to Propene Using CO₂ as a Soft Oxidant Over In-TUD-1 Catalyst

Propene is one of the major platform petrochemicals, traditionally produced on an industrial scale via steam cracking of propane. As an alternative route, the oxidative dehydrogenation of propane (ODHP) offers a more energy-efficient pathway to obtain propene. In the current context of CO₂ mitigation, carbon dioxide can serve as a soft oxidant in the ODH of propane, reducing coke formation and enabling CO₂ utilization. Indium-based catalysts have shown promise in this regard, as indium can effectively activate CO₂ and promote reactions such as ODH. A series of indium oxide (In₂O₃) supported on TUD-1 mesoporous silica were prepared using a sol-gel method. The as-prepared catalysts were thoroughly characterized by several characterization techniques like XRD, SAXS, Raman, UV-vis spectroscopy, and TEM analysis. XRD result revealed the crystalline In₂O₃ with exposed (222) planes whereas Brunauer-Emmett-Teller (BET) analysis suggested incorporation of In₂O₃ inside the pores of the TUD-1. The addition of indium decreased the pore diameter of TUD-1 material. Under optimized reaction condition (500°C; C₃H₈: CO₂: N₂ = 1: 4: 5; GHSV = 6000 mL g^-1 h^-1) 10In-TUD-1 catalyst achieved 16% propane conversion with 70% propene selectivity.