Nickel Catalyst Preparation with Amine Additives for Selective Hydrogenation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current catalysts for selective hydrogenation of polyunsaturated compounds, such as those from steam cracking, face limitations in achieving optimal activity and selectivity due to factors like particle size distribution and diffusion limitations, and existing organic additives do not consistently provide superior performance.
Innovation Solution
A process using a nickel catalyst supported on alumina, prepared with specific organic additives like amines or amides, which involves steps of impregnating the support with a nickel precursor and an organic compound, followed by drying and optional calcination, to enhance catalytic activity and selectivity in hydrogenation reactions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If conventional organic additives (carboxylic acid, cyclic oligosaccharide) are used to prepare nickel catalysts, then catalyst preparation is simplified, but catalytic activity and selectivity do not achieve optimal performance
Solution Approach 1:
The patent changes the chemical parameters of the organic additive from conventional carboxylic acid or cyclic oligosaccharide types to specific compounds containing amine, amide, or amino acid functions. This parameter change in the additive's chemical nature leads to improved nickel particle dispersion and size control, thereby enhancing catalytic activity and selectivity while maintaining ease of preparation through simple impregnation and calcination steps.
2Productivity
If nickel particle size is reduced to increase catalyst activity, then catalytic activity improves, but particle size distribution control becomes more difficult
Solution Approach 1:
The patent introduces organic additives containing amine, amide, or amino acid functions as intermediary substances during catalyst preparation. These additives act as mediators that control nickel precursor deposition and particle formation, enabling precise control over particle size distribution while achieving small particle sizes that maximize catalytic activity. The additives facilitate uniform dispersion and prevent agglomeration during the impregnation and calcination process.
3Productivity
If diffusion limitations are addressed to improve reaction rate, then hydrogenation efficiency improves, but catalyst structure complexity increases
Solution Approach 1:
The patent utilizes the porous structure of alumina support material, enhanced by the presence of organic additives during preparation. The additives influence pore formation and distribution, creating an optimized porous network that facilitates efficient diffusion of hydrogen and polyunsaturated compounds to active sites. This approach improves hydrogenation efficiency while maintaining relatively simple catalyst structure, avoiding the need for complex multi-component or hierarchical catalyst designs.
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 improved catalytic performance in terms of activity and selectivity for hydrogenating polyunsaturated compounds, matching or exceeding prior art processes, with specific conditions optimizing nickel particle size and distribution for enhanced reaction efficiency.
Implementation Method 1
catalysts for the selective hydrogenation of polyunsaturated compounds are generally based on metals from group VIII of the periodic classification of the elements such as nickel
Implementation Method 2
selective hydrogenation of polyunsaturated compounds in a hydrocarbon feed
Data Source
AI summary
Selective hydrogenation of polyunsaturated compounds containing at least 2 carbon atoms per molecule contained in a hydrocarbon feed with a final boiling point of 300° C. or less, in the presence of a catalyst having a support formed from alumina and an active phase constituted by nickel, said catalyst being prepared by:i) bringing said support into contact with at least one solution containing at least one precursor of nickel;ii) bringing said support into contact with at least one solution containing at least one organic compound comprising at least one amine function with the empirical formula CxNyHz in which x is in the range 1 to 20, y=1−x and z=2−2x+2, or an amide function, or an amino acid,iii) drying said impregnated support at a temperature of less than 250° C.;steps i) and ii) being carried out separately, in any order, or simultaneously.