Enzymatic Esterification of Polyoxyalkylene Esters
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional chemical processes for producing polyoxyalkylene esters result in the formation of carcinogenic 1,4-dioxane byproducts, limiting production capacity and yield, as they involve exposure to heat and acidic conditions, which is a concern for applications where these esters come into contact with humans or animals.
Innovation Solution
A process involving the esterification of ethoxylated intermediate reactants with monocarboxylic acid acyl donors in the presence of immobilized Candida antarctica lipase B enzyme catalyst at controlled temperatures, achieving a polyoxyalkylene ester composition with greater than 90% fully acylated ester, less than 10% partially acylated ester, and 5 ppm or less of 1,4-dioxane.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If traditional chemical processes are used to produce polyoxyalkylene esters, then production capacity and yield are improved, but carcinogenic 1,4-dioxane byproducts are formed
Solution Approach 1:
The patent changes the fundamental reaction parameters from traditional chemical catalysis (acidic conditions, high temperature) to enzymatic catalysis (neutral conditions, lower temperature). This parameter change eliminates the formation pathway of 1,4-dioxane while maintaining productive esterification, achieving both high yield and safety requirements
Solution Approach 2:
The patent introduces an enzyme catalyst as an intermediary substance to mediate the esterification reaction between polyoxyalkylene alcohol and carboxylic acid. This enzymatic mediator enables the reaction to proceed under mild conditions without generating harmful byproducts, resolving the contradiction between productivity and safety
2Speed
If exposure to heat and acidic conditions is applied during esterification, then reaction rate is improved, but 1,4-dioxane byproduct formation increases
Solution Approach 1:
The patent replaces the mechanical/chemical forcing method (heat and acid catalysis) with a biological catalytic system (enzyme). This substitution maintains high reaction rate through enzymatic activity while eliminating the conditions that lead to 1,4-dioxane formation, achieving both speed and safety
3Object-affected harmful factors
If 1,4-dioxane limit is imposed on production, then product safety is improved, but production capacity is reduced
Solution Approach 1:
The patent takes preliminary action by selecting an enzymatic catalysis pathway from the outset that inherently prevents 1,4-dioxane formation. This preventive approach eliminates the need for post-reaction purification or production limitations, maintaining both safety standards and production capacity
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 method significantly reduces 1,4-dioxane levels and increases the yield of fully acylated polyoxyalkylene ester, ensuring safer and more efficient production while maintaining high product quality.
Implementation Method 1
contacting the reactants with an enzyme catalyst under esterification conditions
Implementation Method 2
the esterification of ethoxylated intermediate reactants with monocarboxylic acid acyl donors
Data Source
AI summary
One aspect of the present invention is a polyoxyalkylene ester composition comprising the reaction product of a polyoxyalkylated alcohol or polyol reactant and an acyl donor wherein the ester has greater than about 85 weight percent of a fully acylated polyoxyalkylene ester, less than about 15 percent of a partially acylated polyoxyalkylene ester, less than about 5 parts per million 1,4-dioxane and an acid number of less than about 20. Another aspect of the invention is a process for making the polyoxyalkylene ester composition that includes the steps of contacting a reaction mixture of an polyoxyalkylated alcohol or polyol reactant and an acyl donor reactant in a reactor and in the presence of an enzymatic catalyst under esterification conditions and recovering the polyoxyalkylene ester.