Isobutene Production via Two-Stage 3-Methylcrotonic Acid Conversion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for producing isobutene from renewable resources are inefficient, ineffective, and lack commercial viability due to low yield and safety concerns in fermentation processes.
Innovation Solution
A method involving the uncoupling of 3-methylcrotonic acid production and conversion steps, where 3-methylcrotonic acid is accumulated in a culture medium during fermentation and then enzymatically converted into isobutene under controlled conditions with minimal gas supply, allowing high yield and easy purification.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If 3-methylcrotonic acid is converted to isobutene during fermentation, then isobutene production occurs, but isobutene concentration in off-gases remains low and purification becomes complex
Solution Approach 1:
The invention divides the isobutene production process into two separate stages: (1) fermentation stage where 3-methylcrotonic acid is produced and accumulated in the culture medium, and (2) conversion stage where accumulated 3-methylcrotonic acid is enzymatically converted to isobutene. This segmentation allows each stage to be optimized independently, resulting in high isobutene concentration and simplified purification.
Solution Approach 2:
The invention performs preliminary accumulation of 3-methylcrotonic acid in the culture medium during fermentation before converting it to isobutene. This preliminary action ensures that when conversion occurs, isobutene is produced in high concentration, facilitating easier purification.
2Productivity
If conventional enzymatic conversion methods are used, then isobutene is produced, but yields are low and operational complexity increases
Solution Approach 1:
The invention separates acid production and isobutene conversion into distinct operational phases, allowing simple fermentation conditions followed by controlled enzymatic conversion of accumulated substrate, improving both yield and operational simplicity.
Solution Approach 2:
The invention changes the concentration parameter by accumulating 3-methylcrotonic acid to high levels during fermentation, then converting this concentrated substrate to isobutene, thereby increasing yield while simplifying the conversion operation.
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 significantly increases isobutene concentration in the off-gas to 20-30% or more, facilitating easier purification and improving safety by reducing oxygen levels, thus enhancing the efficiency and commercial attractiveness of the process.
Implementation Method 1
enzymatically converting 3-methylcrotonic acid into isobutene by: (i) incubating a microorganism expressing an FMN-dependent decarboxylase associated with an FMN prenyml transferase with said liquid culture medium containing 3-methylcrotonic acid
Implementation Method 2
culturing a microorganism capable of producing 3-methylcrotonic acid from a carbon source in a liquid culture medium, thereby producing said 3-methylcrotonic acid so that it accumulates in the liquid culture medium
Data Source
AI summary
Described is a method for the production of isobutene from a carbon source characterized in that it comprises: (a) culturing a microorganism capable of producing 3-methylcrotonic acid from a carbon source in a liquid culture medium, thereby producing 3-methylcrotonic acid so that it accumulates in the liquid culture medium; and (b) enzymatically converting 3-methylcrotonic acid contained in the liquid culture medium obtained in step (a) into isobutene by: (i) incubating a microorganism expressing ap FMN-dependent decarboxylase associated with an FMN prenyl transferase with liquid culture medium containing 3-methylcrotonic acid obtained in step (a); and/or (ii) incubating a FMN-dependent decarboxylase associated with a FMN prenyl transferase with liquid culture medium containing 3-methylcrotonic acid obtained in step (a); thereby producing isobutene; and (c) recovering the produced isobutene.