Copper-Based Catalyst Preparation via Continuous Coprecipitation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional copper-based catalysts for methanol synthesis from CO2 and H2 suffer from low catalytic activity and durability due to sintering, and have reproducibility issues, requiring complex preparation steps that increase production costs and time.
Innovation Solution
A process involving continuous contact of acidic metal salt and precipitant solutions to form a slurry, followed by washing and controlled drying to maintain high water content, and reduction at specific temperatures to prevent sintering, resulting in a catalyst with enhanced activity and durability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional preparation steps (precipitation, aging, washing, filtration, drying, molding, calcining) are used, then catalyst can be obtained, but the preparation process becomes long and complex
Solution Approach 1:
The patent combines multiple preparation steps into a simplified process. Specifically, the precipitation and washing steps are merged into a continuous operation where the precipitate is washed directly in the precipitation reactor without separate filtration and drying steps. The drying and calcining steps are also optimized to occur in a more integrated manner, reducing the overall number of discrete operations required.
Solution Approach 2:
The patent makes the precipitation reactor serve multiple functions: it performs both precipitation and washing operations in sequence. The same reactor vessel is used for adding precipitant, allowing the liquid phase to be drawn off and replaced with wash liquid without transferring the precipitate to another device, thereby giving one piece of equipment multiple operational roles.
2Productivity
If reduction temperature is raised to improve reaction rate, then catalytic activity increases, but copper sintering occurs and durability decreases
Solution Approach 1:
The patent optimizes the reduction temperature parameter to a specific range (300-550°C) that balances reaction rate and catalyst durability. This parameter change ensures that the copper particles are reduced to the metallic state necessary for catalysis while preventing excessive thermal energy that would cause sintering. The calcining temperature is also optimized (280-690°C) to achieve the desired copper oxide phase without premature sintering.
Solution Approach 2:
The patent performs calcining before reduction to pre-prepare the copper oxide structure in a controlled manner. This preliminary thermal treatment at 280-690°C creates a stable oxide phase that is more resistant to sintering during the subsequent reduction step. By preparing the material structure in advance through controlled oxidation, the catalyst maintains better structural integrity when exposed to higher temperatures during reduction and reaction.
3Reliability
If water content is increased to maintain catalyst structure, then catalytic activity is preserved, but drying time increases and productivity decreases
Solution Approach 1:
The patent optimizes the water content parameter to a specific range (8-17% after drying) that maintains catalyst structure and activity while avoiding excessive drying times. This parameter change represents a balance point where sufficient water remains to preserve the copper oxide structure and prevent premature sintering, but not so much that drying becomes prohibitively slow. The drying temperature is also optimized (100-400°C) to achieve this balance efficiently.
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 process achieves high reproducibility and maintains catalytic activity over a long period with improved durability, simplifying the preparation steps and reducing production costs.
Implementation Method 1
a step of continuously bringing an acidic metal salt solution containing copper and a precipitant solution into contact with each other to obtain a slurry solution containing a precipitate of a catalyst precursor
Implementation Method 2
a step of continuously bringing the slurry solution and a wash liquid into contact with each other to wash the precipitate, with substantially keeping the suspended state
Implementation Method 3
pretreatment wherein reduction is carried out at a high temperature makes it possible to obtain a copper-based catalyst which exhibits excellent durability
Implementation Method 4
the main cause of such lowering of catalytic activity of the copper-based catalyst is decrease of surface area due to sintering of copper
Data Source
AI summary
There is provided by the present invention a process for preparing a copper-based catalyst having good catalytic activity, markedly excellent durability and good reproducibility. The process for preparing a copper-based catalyst of the invention is a process for preparing a catalyst composed of metal oxides containing copper oxide as an essential component and is characterized by comprising the following steps: (1) a step of bringing an acidicmetal salt solution containing copper and a precipitant solution into contact with each other to obtain a slurry solution containing a precipitate of a catalyst precursor, and (2) a step of continuously bringing the slurry solution and a wash liquid into contact with each other to wash the precipitate, with substantially keeping the suspended state.