Mixed Metal Oxide Extrudate Catalyst for Tri-Reforming
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current catalysts for tri-reforming of biogas at high pressures and temperatures are prone to deactivation due to carbon deposition and lack stability, leading to inefficiencies and short lifetimes, and existing catalyst forms like powders face challenges in commercial-scale applications due to pressure drop and mass transfer limitations.
Innovation Solution
Development of a mixed metal oxide extrudate catalyst, specifically a Ce0.6Zr0.4O2 supported NiMg catalyst, is created through ball milling, binder addition, and extrusion processes to produce a stable form that can withstand high pressures and temperatures, optimizing the catalyst's structure for commercial-scale tri-reforming reactions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If powder form catalyst is used to maximize mass transfer efficiency, then mass transfer efficiency is improved, but pressure drop increases significantly making it unsuitable for commercial fixed bed reactors
Solution Approach 1:
The patent changes the physical form parameter of the catalyst from powder to extrudate (pellet) form. This parameter change maintains adequate mass transfer efficiency while dramatically reducing pressure drop in fixed bed reactors, making the catalyst suitable for commercial-scale applications.
Solution Approach 2:
The patent creates a composite extrudate structure containing the active catalyst material distributed within a mechanically robust pellet form. This composite approach combines the mass transfer benefits of fine catalyst particles with the flow characteristics of larger pellet structures.
2Productivity
If high reaction temperature (800-1000°C) is used for tri-reforming, then reaction rate is improved, but catalyst deactivation occurs over relatively short periods
Solution Approach 1:
The patent employs a composite material system consisting of Ni-based active phase supported on redox-active supports (CeO2, (Ce,Zr)O2) and magnesia. This composite structure provides high reaction activity at elevated temperatures while the redox supports prevent metal sintering and reduce carbon deposition, thereby maintaining catalyst stability.
Solution Approach 2:
The redox support materials act as intermediaries that facilitate oxygen transfer to the metal particles, preventing carbon deposition and metal sintering. The supports mediate between the harsh reaction conditions and the sensitive metal catalyst, protecting it from deactivation.
3Productivity
If Ni-based catalyst is used for methane reforming, then catalytic performance is improved, but gradual deactivation occurs
Solution Approach 1:
The patent creates a composite catalyst system where Ni-based active phase is supported on redox-active materials (CeO2, (Ce,Zr)O2) and magnesia. This composite structure maintains the high catalytic performance of Ni while the support materials prevent deactivation mechanisms including carbon deposition and metal sintering, thereby extending catalyst lifetime.
Solution Approach 2:
The patent converts the potential harm of carbon deposition into a beneficial cycle by using redox supports that can supply oxygen to gasify carbon deposits in situ. The carbon deposition problem is transformed into a self-cleaning mechanism through the redox properties of the support materials.
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 mixed metal oxide extrudate catalyst demonstrates enhanced stability and performance at pressures up to 30 bar and temperatures of 700-1000°C, achieving high CH4 conversion and controlled H2/CO molar ratios, with a coking rate of 2.2×10−4 g/(gcat*h) or less, suitable for large-scale tri-reforming applications.
Implementation Method 1
The mixed metal oxide extrudate catalyst demonstrates enhanced stability and performance at pressures up to 30 bar and temperatures of 700-1000°C, achieving high CH4 conversion and controlled H2/CO molar ratios
Implementation Method 2
Redox support materials such as CeO2 and (Ce,Zr)O2 could reduce carbon deposition and prevent metal sintering due to high oxygen storage capability and strong metal-support interaction
Implementation Method 3
a major problem during the bi-reforming process is carbon deposition that can deactivate the catalyst
Data Source
AI summary
Methods of making a Ce0.6Zr0.4O2 supported NiMg catalyst extrudate are provided. In some aspects, the methods include preparing a ceria-zirconia solution comprising Ce(NO3)3.6H2O, ZrO(NO3)2xH2O, and water; forming a precipitate; drying and calcining the precipitate to produce a Ce0.6Zr0.4O2; adding a nickel-magnesium solution to the Ce0.6Zr0.4O2 to produce the NiMg/Ce0.6Zr0.4O2; and drying and calcining a wet extrudate of the NiMg/Ce0.6Zr0.4O2 to produce the Ce0.6Zr0.4O2 supported NiMg catalyst extrudate. Ce0.6Zr0.4O2 supported NiMg catalyst extrudates made by the methods are also provided.