Fluoroether Purification via Countercurrent Extraction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for producing fluoroethers result in impurities, particularly fluorine-containing alkyl alcohols, which are difficult to separate efficiently, leading to low purity levels and increased costs due to the need for repeated rinsing with large amounts of water, making scale expansion impractical.
Innovation Solution
A countercurrent separation method using water to purify fluoroether crude solutions, reducing the concentration of fluorine-containing alkyl alcohols to 0.001 GC% or less, allowing for efficient production of highly pure fluoroethers suitable for scale expansion and reuse of unreacted raw materials.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If repeated rinsing with water is performed to reduce fluorine-containing alkyl alcohol concentration to 0.001 GC% or less, then purity of fluoroether is improved, but water consumption increases to about 4 times the volume of crude solution
Solution Approach 1:
The patent divides the purification process into two distinct stages: (1) initial rinsing with water to remove the majority of fluorine-containing alkyl alcohol impurities, and (2) subsequent extraction with a water-immiscible organic solvent to remove remaining trace impurities. This segmentation allows achieving high purity (0.001 GC% or less) without requiring excessive water consumption (about 4 times volume), as each stage targets different concentration levels of impurities with the most appropriate method.
Solution Approach 2:
The patent introduces a water-immiscible organic solvent as an intermediary substance to perform the second stage of purification. This intermediary solvent selectively extracts remaining fluorine-containing alkyl alcohol impurities from the fluoroether solution without mixing with water, enabling efficient removal of trace impurities while minimizing water usage in the overall process.
2Manufacturing precision
If fluorine-containing alkyl alcohol concentration is reduced from about 9 GC% to 0.001 GC% or less by repeated rinsing, then purity is improved, but processing time increases due to multiple rinsing steps
Solution Approach 1:
The patent segments the purification process into two efficient stages: initial water rinsing to remove bulk impurities quickly, followed by organic solvent extraction to remove trace impurities in a single step. This segmentation reduces total processing time compared to multiple sequential water rinsing steps, as the organic solvent extraction achieves final purification in one operation rather than requiring multiple repeated rinsing cycles.
Solution Approach 2:
The water-immiscible organic solvent acts as an intermediary that rapidly extracts remaining impurities in a single extraction step, significantly reducing processing time compared to repeated water rinsing. The solvent's selective solubility properties allow it to efficiently remove trace fluorine-containing alkyl alcohol impurities without requiring multiple processing cycles.
3Manufacturing precision
If fluorine-containing alkyl alcohol is separated from fluoroether by rectification, then purification is attempted, but separation is ineffective because they form an azeotropic system
Solution Approach 1:
The patent takes out the fluorine-containing alkyl alcohol impurity from the fluoroether solution through liquid-liquid extraction using a water-immiscible organic solvent. This extraction method bypasses the azeotropic limitation of rectification by utilizing differential solubility in two immiscible phases, allowing effective separation without requiring the impurities to have different volatilities.
Solution Approach 2:
The patent changes the separation parameter from temperature-based (rectification) to solubility-based (extraction). By using a water-immiscible organic solvent, the separation relies on differential partitioning of fluoroether and fluorine-containing alkyl alcohol between two liquid phases, avoiding the azeotropic composition problem that prevents effective separation by distillation.
4Manufacturing precision
If fluorine-containing alkyl alcohol is removed by crystallization method, then separation is attempted, but the method is ineffective because fluorine-containing alkyl alcohol is not frozen at its freezing point
Solution Approach 1:
The patent uses liquid-liquid extraction to take out fluorine-containing alkyl alcohol impurities from the fluoroether solution using a water-immiscible organic solvent. This extraction method works at ambient temperature and does not require freezing the impurity, overcoming the limitation of crystallization methods for substances that remain liquid at their freezing points.
Solution Approach 2:
The patent changes the separation mechanism from temperature-based phase change (crystallization/freezing) to solubility-based partitioning in immiscible liquids. By using extraction with a water-immiscible organic solvent, the separation occurs at constant temperature without requiring the impurity to undergo phase change, making the process effective for fluorine-containing alkyl alcohols that do not freeze readily.
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 effectively separates fluoroether and fluorine-containing alkyl alcohol phases, reducing water consumption and processing time, enabling high-purity fluoroether production suitable for applications in electrolytes and semiconductors, with a moisture content of 50 ppm or less.
Implementation Method 1
performing countercurrent separation on a crude solution of fluoroether including a fluorine-containing alkyl alcohol as an impurity using water
Implementation Method 2
the fluorine-containing alkyl alcohol is eluted in water by rinsing the crude solution of fluoroether with water
Data Source
AI summary
The present invention provides a method for efficiently producing a highly pure fluoroether containing remarkably low concentration of a fluorine-containing alkyl alcohol. The method is suited for scale-up and specifically includes performing countercurrent separation of a crude solution of fluoroether including a fluorine-containing alkyl alcohol as an impurity using water.