Organic Amine Addition in Linear Alpha-Olefin Oligomerization
Solution Overview
Problem
Existing methods for preparing linear alpha-olefins through ethylene oligomerization using homogeneous catalysts face issues such as HCl formation during catalyst deactivation, leading to low product purity and thermal stability, along with high sensitivity to runaway reactions and fouling in the reactor system.
Innovation Solution
The method involves adding an organic amine into the oligomerization reactor and/or reactor outlet piping system to prevent HCl formation, enhance mixing efficiency, and suppress side reactions, using a catalyst comprising zirconium and aluminum components, with the amine being recycled and mixed using various devices to maintain reaction stability and purity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If catalyst deactivation is performed using caustic, then catalyst removal is achieved, but HCl formation occurs leading to isomerization of LAO and reduced product purity
Solution Approach 1:
An organic amine is introduced as an intermediary substance that reacts with HCl to form a salt, thereby preventing HCl from catalyzing unwanted isomerization reactions. The amine acts as a mediator between the caustic deactivation process and the LAO product, eliminating the harmful effect of HCl formation while maintaining effective catalyst deactivation.
2Reliability
If conventional catalyst deactivation and removal is performed, then catalyst is removed from the stream, but mixing efficiency between linear alpha-olefins and caustic is limited
Solution Approach 1:
The organic amine serves as a mixing intermediary that enhances the interaction between the caustic phase and the linear alpha-olefin stream. By forming a salt with HCl, the amine facilitates better phase interaction and mass transfer, thereby improving mixing efficiency without compromising catalyst removal effectiveness.
3Productivity
If ethylene oligomerization is performed using homogeneous catalyst, then linear alpha-olefins are produced, but side reactions occur causing fouling and plugging in reactor outlet piping
Solution Approach 1:
The invention converts the harmful effect of HCl formation into a beneficial outcome by intentionally allowing HCl to form during catalyst deactivation and then neutralizing it with the organic amine. This controlled approach prevents uncontrolled side reactions and fouling that would otherwise occur, transforming a potential problem into a solution.
4Device complexity
If catalyst deactivation is performed without organic amine, then process simplicity is maintained, but product thermal stability is limited
Solution Approach 1:
The organic amine is introduced as a temporary intermediary that protects the thermal stability of the LAO product during the catalyst deactivation process. After fulfilling its protective function, the amine can be easily removed through distillation or extraction, restoring process simplicity while having temporarily ensured product stability during the critical deactivation phase.
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 eliminates HCl formation, increases product purity and thermal stability, reduces reaction sensitivity, prevents fouling, and improves mixing efficiency, while allowing for cost-effective recycling of the amine, thereby enhancing the overall process economics.
Implementation Method 1
at least one organic amine is added into the oligomerization reactor and/or into the reactor outlet piping system... during the catalyst deactivation and catalyst removal step HCl is formed which may catalyse isomerization of LAO
Implementation Method 2
the amine is mixed with the reactor outlet stream by means of a mixing device, preferably a static mixer, a dynamic mixer, an ultrasonic mixer or a ventury mixing nozzle
Implementation Method 3
The organic amine may be preferably removed from the reactor outlet stream or one or more products by distillation, extraction or adsorption
Implementation Method 4
The organic amine may be preferably removed from the reactor outlet stream or one or more products by distillation, extraction or adsorption
Implementation Method 5
The organic amine may be preferably removed from the reactor outlet stream or one or more products by distillation, extraction or adsorption
Data Source
AI summary
The present invention relates to a method for preparing linear alpha-olefins (LAO) by oligomerization of ethylene in the presence of solvent and homogenous catalyst, comprising the steps of: (i) feeding ethylene, solvent and catalyst into an oligomerization reactor, (ii) oligomerizing the ethylene in the reactor, (iii) removing a reactor outlet stream comprising solvent, linear alpha-olefins, ethylene, and catalyst from the reactor via a reactor outlet piping system, (iv) transferring the reactor outlet stream to a catalyst deactivation and removal step, and (v) deactivating and removing the catalyst from the reactor outlet stream, characterized in that at least one organic amine is added into the oligomerization reactor and/or into the reactor outlet piping system.