This dissertation advances catalytic and membrane-based systems for the Oxidative Coupling of Methane (OCM), a promising method to convert methane—a major component of natural gas—into valuable hydrocarbons like ethylene. The work addresses two key challenges: (i) improving catalyst performance at conditions relevant for industrial application and (ii) process intensification by developing efficient oxygen delivery systems.

Methane is abundant and affordable, but traditional methods for ethylene production, such as steam cracking, are highly energy-intensive. OCM provides a more efficient alternative by enabling methane’s partial oxidation to form higher hydrocarbons. However, improving yields, product selectivity, and reducing operational costs remain significant challenges. This research uses a multidisciplinary approach, combining catalyst synthesis, membrane reactors, and process optimization to overcome these hurdles.

The first part of this Thesis focuses on catalyst development to maximize higher hydrocarbon selectivity and yield. A lanthanum oxide catalyst synthesized via novel MOF-mediated route achieved notable improvements compared to traditional synthesis routes, attributed to its small particle size, high surface area, and enhanced basicity. On the other hand, another catalytic system based on strontium-doped neodymium oxide, delivered higher hydrocarbon yields, exceeding 18%, showcasing their potential for efficient methane conversion.

The second part of this Thesis explores Mixed Ionic Electronic Conducting (MIEC) membranes as an innovative solution for oxygen delivery. These membranes selectively transport oxygen ions from air into the reaction zone, eliminating the need for costly pure oxygen. Two MIEC membranes—BSCF and CSFM—were evaluated for their performance. BSCF membranes exhibited higher oxygen flux, resulting in greater methane conversion. On the other hand, CSFM membranes provided higher selectivity for hydrocarbon products but delivered lower methane conversion because of limited oxygen flux. Both membranes demonstrated excellent thermal and chemical stability under OCM conditions, highlighting their long-term viability.

The integration of advanced catalysts and MIEC membranes reveals their complementary roles: catalysts enhance selectivity and yield, while membranes provide an economical and safer means of oxygen supply at concentrations that maximize oxidative coupling and reduce total oxidation. Together, these innovations address the key technical and economic barriers, paving the way for scaling OCM from research to industrial application.

Beyond OCM, this work offers broader opportunities. The membrane reactor system can be applied to other oxidative processes where MIEC membranes show potential for integrating oxygen delivery and catalytic reactions across various industries. These advancements contribute to a more energy-efficient and sustainable approach to chemical manufacturing, reducing environmental impacts in the petrochemical sector.