Perovskite Lanthanide Catalysts for Oxidative Coupling of Methane
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current catalysts and catalytic processes for oxidative coupling of methane (OCM) and oxidative dehydrogenation (ODH) lack effectiveness, leading to inefficiencies in methane conversion and ethylene selectivity, hindering the commercialization of these reactions.
Innovation Solution
Development of catalytic materials comprising perovskites and lanthanide-based catalysts with specific formulas, combined with diluents or supports, which enhance methane conversion and C2 selectivity, and are designed for use in oxidative coupling reactions at specific temperatures and linear velocities.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If conventional catalysts are used for oxidative coupling of methane, then the reaction can proceed, but methane conversion rate is low and C2 selectivity is poor
Solution Approach 1:
The patent employs composite catalyst materials comprising multiple components: transition metal oxides (Fe, Co, Ni, Cu, Mn, Zn), alkaline earth metal oxides (Ca, Sr, Ba), and lanthanide oxides (La, Ce, Pr, Nd, Gd, Dy, Ho, Er, Tm, Lu). These composite materials create synergistic effects where different components contribute to specific catalytic functions, achieving both high methane conversion and superior C2 selectivity simultaneously
Solution Approach 2:
The catalyst formulation uses specific ratios of different metal oxides and supports (alumina, silica, titania, zirconia, hafnia) to create localized active sites with optimized properties. The support materials provide structural framework while the metal oxides create active catalytic centers with specific electronic and geometric properties tailored for OCM reaction
2Productivity
If high temperatures are used for oxidative coupling of methane, then reaction rate increases, but energy consumption increases and unwanted side reactions occur
Solution Approach 1:
The patent modifies the catalytic parameters by introducing multiple metal oxides with different activation energies and reaction pathways. This creates a distribution of active sites that can operate at different temperature ranges, allowing the reaction to proceed at lower temperatures while maintaining high rates through the combined effect of multiple catalytic mechanisms
Solution Approach 2:
The composite catalyst system provides continuous catalytic activity through multiple active sites that operate simultaneously at different temperature zones. The heat generated by exothermic reactions at certain sites can be utilized by other sites, creating a self-sustaining thermal field that maintains high reaction rates without requiring continuously high external temperature
3Productivity
If catalyst load is increased to improve conversion, then productivity increases, but cost and complexity increase
Solution Approach 1:
The support materials (alumina, silica, titania, zirconia, hafnia) serve multiple functions simultaneously: they provide structural support, thermal stability, mass transfer pathways, and additional catalytic activity. The metal oxides also perform multiple functions including methane activation, C-C bond formation, and product selective desorption, reducing the need for separate functional components
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The proposed catalytic materials achieve methane conversion rates greater than 20% and C2 selectivity greater than 50% in the oxidative coupling of methane, improving reaction efficiency and stability at temperatures ranging from 550°C to 750°C.
Implementation Method 1
Catalysis is the process in which the rate of a chemical reaction is either increased or decreased by means of a catalyst. Positive catalysts lower the rate-limiting free energy change to the transition state, and thus increase the speed of a chemical reaction at a given temperature.
Implementation Method 2
the catalytic reaction generally occurs on the surface of the heterogeneous catalyst. Thus, for the catalytic reaction to occur, the reactants must diffuse to and/or adsorb onto the catalyst surface.
Implementation Method 3
This reaction is exothermic (ΔH = -67kcals/mole)
Data Source
Figure 1~2A
Figure 2B~2D
Figure 2E~2F
AI summary
Catalysts, catalytic forms and formulations, and catalytic methods are provided. The catalysts and catalytic forms and formulations are useful in a variety of catalytic reactions, for example, the oxidative coupling of methane. Related methods for use and manufacture of the same are also disclosed.