Perovskite Catalysts for Stable Oxidative Methane Coupling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
There is a significant need in the petrochemical industry for highly selective heterogeneous catalysts to convert unreactive hydrocarbon feedstocks like methane into reactive intermediates, particularly for the oxidative coupling of methane, as existing catalysts face issues with stability and selectivity.
Innovation Solution
The development of catalysts comprising lanthanides, lanthanide oxides, or perovskites with C2+ selectivity of at least 20% when used in oxidative coupling of methane at 400°C and 2 barg pressure, and the use of supported catalysts with a support to enhance stability, along with the inclusion of steam in the feed gas to improve catalytic performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional catalysts are used for oxidative coupling of methane, then the reaction can proceed, but the catalyst stability and C2+ selectivity are insufficient
Solution Approach 1:
The patent employs composite catalyst systems combining perovskite materials (such as LaMnO3, SrMnO3) with other metal oxides or supported on specific carriers. These composite structures integrate the high stability of perovskites with enhanced selectivity properties, resolving the contradiction between catalyst stability and C2+ selectivity by synergistically combining multiple materials with complementary functions
Solution Approach 2:
The patent systematically optimizes catalytic parameters including operating temperature (400-700°C), pressure (1-10 barg), oxygen-to-methane ratio, and space velocity to maximize C2+ selectivity while maintaining catalyst stability. By precisely controlling these parameters, the patent achieves high ethylene and propylene yields without sacrificing catalyst longevity
2Productivity
If higher temperatures are used to increase reaction rate, then productivity improves, but catalyst stability and selectivity deteriorate
Solution Approach 1:
The patent identifies optimal temperature windows (400-700°C) where the reaction rate is sufficiently high for industrial productivity while the catalyst structure remains stable. Perovskite-based catalysts maintain structural integrity at these elevated temperatures due to their thermally stable crystal structure, enabling sustained high-rate operation without degradation
Solution Approach 2:
The patent develops catalyst formulations that can operate at high temperatures for extended periods before requiring regeneration or replacement. The use of thermally stable perovskite materials extends catalyst lifetime compared to conventional catalysts, reducing the frequency of catalyst changes while maintaining high productivity
3Productivity
If higher temperatures are used to increase reaction rate, then productivity improves, but C2+ selectivity decreases
Solution Approach 1:
The patent optimizes the temperature profile to achieve maximum C2+ selectivity at specific temperature ranges. The perovskite catalysts exhibit peak ethylene and propylene selectivity at moderate temperatures (400-600°C), and this temperature optimization strategy maintains high productivity while maximizing desired product formation
Solution Approach 2:
The patent creates catalysts with specific local active sites that favor C2+ formation through controlled oxidation states and surface compositions. The perovskite structure provides specific crystallographic planes and surface oxygen species that selectively promote coupling reactions to form ethylene and propylene, maintaining high selectivity even at elevated temperatures
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
These catalysts demonstrate high C2+ selectivity and improved stability, effectively converting methane into ethylene and propylene with enhanced catalytic performance under specified conditions.
Implementation Method 1
Catalysts for oxidative coupling of methane... The OCM process utilizes an OCM active catalyst that is held within an OCM reactor. Methane and oxygen flow through the reactor to produce a mixture of hydrocarbon products.
Implementation Method 2
The catalytic material is a supported catalyst comprising a catalyst on a support. The support increases the stability of the catalyst.
Implementation Method 3
a feed gas including methane, oxygen and steam is used to contact a catalyst or catalytic material in the OCM reaction. The steam increases the catalytic performance of the catalyst.
Data Source
AI summary
Catalysts, catalytic materials having catalysts present on supports and catalytic methods are provided. The catalysts, catalytic material and methods are useful in a variety of catalytic reactions, for example, the oxidative coupling of methane.