Promoted Mixed Oxide Catalysts for Low-Temperature Methane Partial Oxidation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing redox catalysts for methane partial oxidation to syngas face challenges such as high cost, low activity, limited selectivity, and require high operating temperatures due to low surface activity and high activation energy, leading to inefficient methane reforming processes.
Innovation Solution
The use of platinum group-promoted mixed metal oxides, such as perovskites and fluorite-structured materials, with tailored surface promoters like Rhodium, enhances syngas selectivity and reduces operating temperatures by up to 300°C, allowing for efficient methane conversion to syngas at lower temperatures through cyclic redox processes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If conventional redox catalysts are used for methane partial oxidation, then the process can proceed, but high operating temperatures (>800°C) are required due to low surface activity and high activation energy
Solution Approach 1:
The patent modifies the chemical composition parameters of the catalyst by incorporating platinum group metals (Pt, Pd, Rh) into mixed metal oxide structures, creating promoted catalysts that change the activation energy and surface activity parameters, enabling operation at lower temperatures while maintaining high methane conversion rates
Solution Approach 2:
The patent creates composite catalyst materials combining platinum group metals with mixed metal oxides (such as perovskites and fluorite-structured materials), where the composite structure synergistically combines the high catalytic activity of the metal with the redox activity of the oxide, achieving both low-temperature operation and high productivity
2Productivity
If conventional redox catalysts are used, then methane conversion can occur, but syngas selectivity is limited due to non-selective combustion reactions
Solution Approach 1:
The patent applies local quality modification by placing platinum group metal promoters at specific locations on the catalyst surface and within the mixed metal oxide structure, creating localized active sites that favor selective partial oxidation while the bulk material maintains redox stability, thereby improving syngas selectivity without sacrificing conversion rate
3Productivity
If nickel based oxides are used as redox catalysts, then catalytic activity is achieved, but high cost and health and environmental concerns arise
Solution Approach 1:
The patent replaces expensive nickel-based catalysts with cheaper platinum group metal promoters (Pt, Pd, Rh) used in small amounts within mixed metal oxide structures, achieving comparable or superior catalytic activity at lower cost, while also eliminating the environmental and health concerns associated with nickel
Solution Approach 2:
The patent changes the compositional parameters by using platinum group metals in controlled amounts within mixed metal oxide frameworks, modifying the catalytic properties to achieve high activity while maintaining environmental benignity and cost-effectiveness
4Object-affected harmful factors
If iron and manganese based oxides are used, then cost and environmental benignity are improved, but syngas selectivity remains low
Solution Approach 1:
The patent creates composite materials by combining environmentally benign iron or manganese based mixed metal oxides with platinum group metal promoters, where the oxide provides redox stability and environmental friendliness while the metal promoter contributes selective catalytic activity, achieving both environmental benignity and high syngas selectivity
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 promoted mixed oxides exhibit superior syngas selectivity and redox activity at low temperatures, improving energy efficiency by eliminating the need for air separation units and reducing the process complexity, while maintaining high methane conversion rates.
Implementation Method 1
The use of platinum group-promoted mixed metal oxides, such as perovskites and fluorite-structured materials, with tailored surface promoters like Rhodium, enhances syngas selectivity and reduces operating temperatures by up to 300°C, allowing for efficient methane conversion to syngas at lower temperatures through cyclic redox processes.
Implementation Method 2
Our recent studies showed that mixed metal oxides, such as perovskites, can be used as supports to both increase the mechanical integrity of the oxygen reservoir and provide metallic catalytic sites for methane partial oxidation.
Data Source
AI summary
Redox catalysts are provided for “low-temperature” methane partial oxidation in absence of gaseous oxidants. Methods of converting the methane to syngas using the catalysts are also provided. In some aspects, the conversion takes place at temperatures of about 400° C. to about 950° C. The methods can be used to convert methane to syngas containing carbon monoxide and hydrogen gas. In some aspects, the methods are carried out in a fixed bed reactor with reverse flow.