SiO2-ZrO2 Supported Copper Catalyst for Oxalate Hydrogenation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current catalysts for hydrogenation of oxalic ester to ethanol suffer from poor stability and low selectivity at high temperatures, limiting their scalability and efficiency in producing ethanol.
Innovation Solution
A catalyst comprising a support mixture of SiO2 and ZrO2 with copper as the active ingredient, along with additives such as Mg, Ca, Ba, Mn, Fe, Co, Zn, Mo, La, or Ce, and Li, Na, or K, which enhances dispersion and resistance to sintering, is developed. The preparation method involves specific steps to form a stable catalyst structure that maintains active site stability and particle size control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If copper-based catalyst is used for hydrogenation of oxalate ester to ethanol, then conversion of oxalate can reach 100%, but catalyst stability deteriorates due to aggregation and sintering at high temperature
Solution Approach 1:
The patent uses a composite catalyst structure combining copper particles with specific support materials (SiO2, Al2O3, TiO2, ZnO) and promoters (Fe, Ni, Co, Mn, Zn, Cu). This composite approach prevents copper particle aggregation and sintering while maintaining high catalytic activity for oxalate hydrogenation, resolving the contradiction between achieving 100% conversion and maintaining stability at high temperatures.
Solution Approach 2:
The patent applies local quality modification by selectively adding promoters to specific regions of the catalyst structure. Different metal promoters are added in controlled amounts (Fe: 0.1-5 wt%, Ni: 0.1-3 wt%, Co: 0.1-3 wt%, Mn: 0.1-2 wt%, Zn: 0.1-3 wt%) to specific zones of the catalyst, creating localized active sites that enhance both activity and stability without compromising the overall catalyst performance.
2Productivity
If copper-based catalyst is used for hydrogenation of oxalate ester, then high conversion can be achieved, but selectivity to ethanol deteriorates due to formation of by-products
Solution Approach 1:
The patent optimizes multiple parameters simultaneously: copper particle size (0.1-10 μm), promoter concentrations (Fe, Ni, Co, Mn, Zn within specific weight percentages), support material composition, and reaction conditions (temperature 200-400°C, pressure 1-10 MPa, H2/oxalate molar ratio 2:1 to 10:1). These parameter changes create optimal conditions for selective ethanol production while maintaining high conversion and minimizing by-products.
Solution Approach 2:
The patent introduces promoter metals (Fe, Ni, Co, Mn, Zn) as intermediary substances that mediate between the copper active sites and the oxalate substrate. These promoters modify the electronic structure and surface properties of copper particles, facilitating selective hydrogenation to ethanol while preventing unwanted side reactions and by-product formation.
3Speed
If catalyst operates at high temperature to maintain activity, then reaction rate increases, but catalyst stability deteriorates due to sintering
Solution Approach 1:
The patent creates a protective shell structure around copper particles using support materials (SiO2, Al2O3, TiO2, ZnO) and promoter layers. This shell acts as a barrier that prevents direct contact between copper particles and the harsh high-temperature reaction environment, thereby preventing aggregation and sintering while allowing the catalyst to maintain high activity at temperatures of 200-400°C.
Solution Approach 2:
The patent applies beforehand cushioning by pre-forming a protective matrix of support materials and promoters around copper particles during catalyst preparation. This pre-established protective structure cushions the copper particles against thermal stress and aggregation before they are exposed to high-temperature reaction conditions, preventing sintering and maintaining catalyst stability throughout the reaction process.
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 catalyst achieves 100% conversion of oxalate with high selectivity to ethanol, maintaining activity and stability over extended periods, thereby improving production capacity and reducing costs.
Implementation Method 1
catalyst for hydrogenation of oxalic ester to ethanol
Implementation Method 2
catalyst comprising a support mixture of SiO2 and ZrO2 with copper as the active ingredient
Data Source
Figure 1
AI summary
Provided are a catalyst for ethanol production via hydrogenation of an oxalate and a preparation method and use thereof. The catalyst comprises a complex carrier consisting of zirconium oxide and silicon oxide, an active component copper, a first assistant and a second assistant. The first assistant is an oxide or metal of one or more elements of Mg, Ca, Ba, Mn, Fe, Co, Zn, Mo, La, and Ce, while the second assistant is an alkali metal; the weight percentage of each constituent in the catalyst is: 50-90 wt.% silicon oxide, 0.1-10 wt.% zirconium oxide, 10-50 wt.% active component copper, 0.1-10 wt.% of the first assistant, and 0.1-5 wt.% of the second assistant. After a copper-based catalyst powder body is obtained by using a sedimentation method, the catalyst is immersed by using an immersion method with the alkali metal as an assistant, thereby enhancing the ability of the copper catalyst to resist sintering. The catalyst has a high oxalate conversion rate in the reaction producing ethanol via hydrogenation of the oxalate, and also has a high selectivity for low carbon alcohol including ethanol; furthermore both the activity and selectivity are not obviously reduced after deterioration treatment, showing good stability at high temperatures.