Solid Catalyst Component Purification via Sequential Solvent Washing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for producing solid catalyst components for olefin polymerization struggle to achieve both high stereoregularity and rigidity, as Ti species with low stereospecificity remain in the catalyst, limiting the production of polymers with enhanced mechanical properties.
Innovation Solution
A method involving the reaction of a magnesium compound, a titanium halide compound, and an electron donor compound in an inert organic solvent, followed by sequential washing with solvents of specific solubility parameters (8.0 to 9.0, greater than 9.0, and less than 8.0) to remove Ti species with low stereospecificity, resulting in a catalyst capable of producing polymers with high stereoregularity and rigidity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a solid catalyst component is produced by contacting magnesium compound, tetravalent titanium halide compound, and electron donor compound in the presence of inert hydrocarbon compound solvent, then stereoregularity of the resulting polymer is improved to some extent, but Ti species with low stereospecificity remains in the solid catalyst component, making it difficult to achieve both high stereoregularity and high rigidity
Solution Approach 1:
The invention extracts and removes Ti species with low stereospecificity from the solid catalyst component through sequential washing with solvents of increasing solubility parameters. The first washing with SP 8.0-9.0 removes some Ti species, the second washing with SP >9.0 removes additional Ti species, and the third washing with SP <8.0 ensures complete removal, thereby eliminating the harmful component while preserving the desired stereoregularity and rigidity
Solution Approach 2:
The invention changes the solubility parameter of the washing solvent in a specific sequence (8.0-9.0, then >9.0, then <8.0) to systematically remove Ti species with different solubilities. This parameter change approach allows selective removal of low stereospecificity Ti species while maintaining the structural integrity and high stereospecificity of the catalyst component
2Manufacturing precision
If sequential washing with three solvents of different solubility parameters is performed to remove Ti species with low stereospecificity, then both high stereoregularity and high rigidity are achieved, but the washing process complexity increases
Solution Approach 1:
The washing process is segmented into three distinct stages, each using a solvent with a specific solubility parameter range. This segmentation allows systematic removal of Ti species with different solubilities, achieving complete purification while maintaining a structured and manageable process flow that can be easily implemented and controlled
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
This approach efficiently removes Ti species with low stereospecificity, enabling the production of olefin polymers with significantly improved mechanical properties, such as high rigidity and stereoregularity, while maintaining high yield.
Implementation Method 1
washing the resulting product with a first inert organic wash solvent that does not have reactivity with the titanium halide compound, and has a solubility parameter (SP) of 8.0 to 9.0; washing the resulting intermediate product one or more times in the absence of the titanium halide compound with a second inert organic wash solvent that comprises a hydrocarbon compound and does not have reactivity with the titanium halide compound, but has a solubility parameter (SP) of more than 9.0; and washing the resulting product one or more times in the absence of the titanium halide compound with a third inert organic wash solvent that does not have reactivity with the titanium halide compound, and has a solubility parameter (SP) of less than 8.0
Data Source
AI summary
A method for producing a solid catalyst component includes bringing a magnesium compound, a titanium halide compound, and one or more internal electron donor compounds into contact with each other to effect a reaction; washing the resulting product with a first inert organic wash solvent that does not have reactivity with the titanium halide compound, and has a solubility parameter (SP) of 8.0 to 9.0; washing the resulting intermediate product in the absence of the titanium halide compound with a second inert organic wash solvent that includes a hydrocarbon compound and does not have reactivity with the titanium halide compound, but has a solubility parameter (SP) of more than 9.0; and washing the resulting product in the absence of the titanium halide compound with a third inert organic wash solvent that does not have reactivity with the titanium halide compound, and has a solubility parameter (SP) of less than 8.0.