Nickel Catalysts for Selective Olefin Oligomerization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current olefin production methods, such as steam cracking, are inefficient in producing heavier co-products like propene, butenes, and aromatics, and lack selective catalysts for alkene dimerization and oligomerization reactions, leading to non-selective outcomes and high costs in product separation.
Innovation Solution
Development of novel catalyst compositions featuring nickel supported on crystalline silica-based molecular sieve oxides, which are active and selective for oligomerization reactions, allowing for the production of longer chain olefins from light olefins like ethene and propene, with specific preparation methods including impregnation, calcination, and reduction processes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If steam cracking processes are used for olefin production, then ethene production capacity increases, but the yield of heavier co-products such as propene, butenes and aromatics decreases
Solution Approach 1:
The invention segments the olefin production process into two distinct stages: first, steam cracking produces abundant ethene; second, a separate oligomerization stage using nickel-based catalysts converts ethene into heavier olefins (propene, butenes, etc.). This segmentation allows each stage to be optimized independently, resolving the contradiction between maximizing ethene production and obtaining heavier co-products.
Solution Approach 2:
The nickel-based microporous and mesoporous catalysts act as intermediaries that facilitate the transformation of ethene (abundant from steam cracking) into heavier olefins. These catalysts mediate the oligomerization reaction, enabling the conversion of excess ethene into valuable heavier products without requiring direct modification of the steam cracking process.
2Productivity
If conventional catalysts are used for alkene oligomerization, then the reaction proceeds, but selectivity towards desired products is poor leading to high separation costs
Solution Approach 1:
The invention employs nickel-based microporous and mesoporous catalysts where the porous structure plays a critical role in enhancing product selectivity. The pore size and structure control which transition states are stabilized and which products can form, thereby increasing selectivity towards desired oligomerization products while maintaining reaction productivity.
Solution Approach 2:
The invention changes key catalyst parameters including the use of nickel as the active metal, the incorporation of microporous and mesoporous structures, and the creation of specific active sites (Ni0, Ni+, Ni2+). These parameter changes fundamentally improve both the reaction rate and product selectivity, reducing the need for costly separation processes.
3Manufacturing precision
If zeolite frameworks are used to stabilize confined reactants and transition states, then catalytic rates and selectivity are influenced, but additional catalytic diversity beyond size exclusion is limited
Solution Approach 1:
The invention creates composite catalyst systems that combine nickel metal particles with microporous and mesoporous support materials. This composite structure provides both the size-exclusion selectivity of porous materials and the catalytic activity of nickel, while the combination creates additional catalytic diversity through synergistic effects that go beyond what either component could achieve alone.
Solution Approach 2:
The nickel-based catalysts exhibit multi-functionality by providing multiple active sites (Ni0, Ni+, Ni2+) and multiple reaction pathways within a single catalyst system. This universality allows the catalyst to perform various oligomerization reactions with different selectivities, enhancing catalytic diversity while maintaining high selectivity through the porous structure.
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 catalysts demonstrate high stability, selectivity, and reproducibility in oligomerization reactions, enhancing the production of higher molecular weight compounds with improved selectivity towards desired products, reducing the need for costly separation processes and increasing the yield of heavier olefins.
Implementation Method 1
nickel supported on crystalline silica-based molecular sieve oxides, which are active and selective for oligomerization reactions
Implementation Method 2
Zeolites, molecular sieves, and related microporous and mesoporous materials have the ability to control the access of reactants and products based on their size and shape to catalytically active sites within the pores of these materials
Implementation Method 3
a zeolite framework of oxygen atoms can stabilize confined reactants and transition states by van der Waals forces
Data Source
AI summary
A novel catalyst composition and its use in the oligomerization reaction converting a portion of a C4 to C5+ alkene feed stream to C4 to C6+ olefin derivatives. The catalyst comprises a Group VIII metal selected from the group consisting of nickel, iron, cobalt, and combinations thereof, on a support. The support can be silica, silicon dioxide, titanium dioxide, metal modified silica, silica-pillared clays, silica-pillared micas, metal oxide modified silica-pillared mica, silica-pillared tetrasilicic mica, silica-pillared taemolite, zeolite, molecular sieve, and combinations thereof. The catalyst composition is an active and selective catalyst for the catalytic oligomerization of alkenes to olefins and olefin derivatives.