Adsorbent Bed Mitigates Catalyst Inhibition in Olefin Polymerization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Polymerization processes, especially olefin polymerization, are sensitive to catalyst poisons formed by the reaction of non-conjugated diene monomers with quenching agents and aluminum alkyl adducts, leading to the formation of undesirable oxygenates that reduce catalyst activity in recycle streams.
Innovation Solution
A process involving a recycle stream treated with an adsorbent bed comprising at least two adsorbents, such as zeolitic molecular sieves and hybrid zeolite in alumina, to remove excess quenching agents and higher molecular weight oxygenates, thereby preventing their entry into the polymerization reactor and maintaining catalyst activity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If non-conjugated diene monomers are used in the polymerization process, then the polymer product properties are improved, but oxygenate contaminants are formed that poison the catalyst
Solution Approach 1:
The adsorbent bed is positioned in the recycle stream before the stream enters the polymerization reactor, performing preliminary removal of oxygenate contaminants. This prevents the oxygenates from reaching and poisoning the catalyst, while allowing the diene monomers to proceed to polymerization and form high-quality polymer products.
Solution Approach 2:
An adsorbent bed containing specialized adsorbent material is introduced as an intermediary component in the recycle stream. This adsorbent selectively interacts with and removes oxygenate contaminants through adsorption, while allowing the diene monomers and other necessary components to pass through to the reactor.
2Reliability
If adsorbent bed is added to remove oxygenates, then catalyst activity is maintained, but device complexity increases
Solution Approach 1:
The adsorbent bed is designed to perform multiple functions within a single unit: removing oxygenate contaminants, maintaining catalyst activity, and potentially removing other impurities. This multi-functionality reduces the need for separate treatment units and minimizes overall system complexity while ensuring reliable catalyst performance.
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
Effectively reduces or eliminates catalyst poisons by removing C1 to C40 oxygenates from the recycle stream, enhancing the stability and efficiency of the polymerization process by maintaining catalyst activity and improving polymer product quality.
Implementation Method 1
contacting at least a portion of the recycle stream with an adsorbent bed to produce a treated recycle stream, where the adsorbent bed comprises at least two adsorbents to remove excess quenching agent and C 1 to C 40 oxygenates
Implementation Method 2
In embodiments where the quenching agent comprises water, desirable adsorbents for removing water from the recycle stream include molecular sieves which comprise zeolitic materials
Data Source
Figure 1
Figure 2a
Figure 2b
AI summary
This disclosure relates to a process for polymerization comprising providing a recycle stream, wherein the recycle stream comprises one or more C6 to C12 conjugated or non- conjugated diene monomers and one or more C1 to C40 oxygenates. The recycle stream is contacted with an adsorbent bed to produce a treated recycle stream; wherein the adsorbent bed comprises at least two adsorbents to remove quenching agent and C1 to C40 oxygenates.