Homogeneous Catalyst Solution for Selective 1-Hexene Production
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing catalyst compositions for selective ethylene oligomerization, such as those used in producing 1-hexene, face challenges including short shelf life, poor solubility of components, precise metering requirements, and susceptibility to degradation, limiting their operational window and efficiency.
Innovation Solution
A two-step method for preparing a homogenous catalyst by separately mixing and storing pre-catalyst solutions containing a chromium source and a ligand, and an organoaluminum compound with a modifier, then simultaneously injecting them into a reaction vessel or solvent feed, ensuring premixing and extending catalyst life.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a homogenous catalyst comprising chromium compound, ligand, modifier and activator is prepared for selective ethylene oligomerization, then productivity and selectivity are improved, but the catalyst shelf life deteriorates due to degradation on a timescale of equal or greater than approximately one day
Solution Approach 1:
The catalyst system is divided into separate components (chromium compound, ligand, modifier, activator) that are stored separately and only combined immediately before use. This segmentation prevents premature reactions and degradation, extending shelf life while maintaining high productivity when the catalyst is activated.
Solution Approach 2:
The catalyst components are prepared and stored in advance in their stable, inactive forms, then activated immediately before use. This preliminary preparation allows the system to maintain high productivity when needed while avoiding degradation during storage by keeping components separate.
2Manufacturing precision
If all catalyst constituents are meticulously metered into the reactor to adjust productivity very precisely, then manufacturing precision is improved, but device complexity increases due to requirement for dosing pumps and prohibition of slurry systems
Solution Approach 1:
The invention uses slurry systems with liquid carriers to transport catalyst components, replacing complex dosing pump systems. The catalyst components are suspended in a liquid medium that can be pumped and delivered through simple hydraulic systems, reducing device complexity while maintaining precise productivity control through slurry concentration adjustment.
Solution Approach 2:
Multiple catalyst components are combined into a single slurry stream, eliminating the need for separate dosing systems for each component. This merging simplifies the delivery system while maintaining the ability to precisely control productivity through slurry flow rate and concentration management.
3Reliability
If the catalyst components are mixed and immediately transferred to the oligomerization reactor to avoid decomposition, then catalyst activity is maintained, but loss of time occurs due to the need for immediate transfer and minimum transportation time
Solution Approach 1:
Catalyst components are prepared and stored in advance in stable, separate forms. The slurry system allows components to be pre-mixed with the liquid carrier and stored until needed, eliminating the need for immediate transfer while maintaining catalyst activity. The preliminary preparation in slurry form enables delayed activation without degradation.
Solution Approach 2:
A liquid carrier serves as an intermediary medium that stabilizes the catalyst components during storage and transport. The carrier prevents premature reactions and degradation, allowing the catalyst to be prepared in advance and transferred at convenient times without losing activity.
4Productivity
If some catalyst components are used in the process, then productivity is achieved, but poor solubility of components in aromatic solvents deteriorates the homogeneity of the catalyst solution
Solution Approach 1:
A liquid carrier acts as an intermediary solvent that improves the solubility and homogeneity of catalyst components. The carrier medium facilitates uniform distribution of all catalyst constituents, ensuring a homogeneous catalyst solution while maintaining high productivity.
Solution Approach 2:
The invention changes the solvent parameter by using a liquid carrier with different solubility properties compared to traditional aromatic solvents. This parameter change improves the dissolution of poorly soluble catalyst components, achieving homogeneous catalyst solutions that maintain high oligomerization activity.
Data Source
AI summary
A method for preparing a homogenous catalyst for use in preparing a linear alpha olefin includes: preparing a first pre-catalyst solution by mixing a chromium source and a ligand in a first solvent, wherein the first pre-catalyst solution is stored in a first vessel; preparing a second pre-catalyst solution by mixing an organoaluminum compound and a modifier in a second solvent, wherein the second pre-catalyst solution is stored in a second vessel; and simultaneously feeding the first pre-catalyst solution and the second pre-catalyst solution directly into a reaction vessel, wherein the reaction vessel includes a third solvent.