Acid-Stable Esterases for Polyester Depolymerization

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current plastic recycling technologies, particularly enzymatic depolymerization processes, face challenges such as high costs due to the need for base addition to maintain pH and the production of salts during terephthalic acid recovery.

Innovation Solution

The use of specific polyester-degrading esterases, derived from a metagenome-derived cutinase, that maintain high activity and thermal stability in acidic conditions between pH 3 and 6, reducing the need for base addition and minimizing salt production.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If bases are massively added to maintain pH during enzymatic depolymerization, then enzyme activity is maintained, but operational costs increase and salt production increases

Engineering Contradiction:

Improveenzyme activityVSAvoidoperational cost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The invention changes the pH parameter from neutral/basic to acidic conditions (pH 2-6), which fundamentally alters the chemical environment. This parameter change allows the use of acid-stable enzymes that do not require base addition for pH maintenance, thereby resolving the contradiction between maintaining enzyme activity and reducing operational costs

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The invention converts the harmful effect of acid production during depolymerization into a beneficial feature. Instead of treating acid as a problem to be neutralized with bases, the process embraces acidic conditions as the optimal environment for enzyme operation, eliminating the need for base addition and salt production while maintaining high enzyme activity

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

2Reliability

If bases are massively added to maintain pH during enzymatic depolymerization, then enzyme activity is maintained, but environmental impact increases

Engineering Contradiction:

Improveenzyme activityVSAvoidenvironmental impact

Core Design Contradiction:

ReliabilityVSObject-generated harmful factors

Solution Approach 1:

By changing the pH parameter to acidic conditions, the invention eliminates the need for base addition and subsequent salt production, thereby removing a significant source of environmental pollution while maintaining effective enzyme catalysis

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The invention transforms the acid byproduct of depolymerization from an environmental hazard requiring neutralization into the desired operating condition, eliminating harmful salt waste and reducing environmental impact while preserving enzyme functionality

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

3Quantity of substance

If strong acids are used for terephthalic acid recovery by precipitation, then acid recovery is achieved, but salt production increases significantly

Engineering Contradiction:

Improveterephthalic acid recoveryVSAvoidsalt production

Core Design Contradiction:

Quantity of substanceVSLoss of substance

Solution Approach 1:

The invention changes the pH parameter of the depolymerization process to acidic conditions, which means the acid byproduct is already in the appropriate form for direct recovery. This eliminates the need for additional strong acid addition and subsequent salt formation during terephthalic acid precipitation

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The process generates acid in situ during depolymerization, which directly serves the dual purpose of maintaining optimal enzyme activity and providing the acid needed for terephthalic acid recovery, thereby eliminating the need for external acid addition and salt production

Inventive Principle:

Principle #25Self-service

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 enhances the economic and industrial viability of polyester depolymerization by maintaining enzymatic activity and thermal stability in acidic conditions, thereby reducing operational costs and environmental impact.

Implementation Method 1

specific polyester degrading enzymes, derived from the amino acid sequence as set forth in SEQ ID No 1... having a polyester degrading activity at a pH between 3 and 6

Methodology Applied

Scientific EffectEnzymatic hydrolysis: Hydrolysis

Data Source

PatentUS20250034347A1Use of esterases

Publication Date: 2025.01.30 CARBIOS

AI summary

The present invention relates to the use of specific enzymes, more particularly of specific esterases having a polyester degrading activity, for the degradation of polyester or polyester containing material in acidic conditions at a pH between 3 and 6. The present invention also relates to a process for degrading polyester or polyester containing material, such as plastic products, comprises a step of enzymatic depolymerization implemented in acidic conditions at a pH between 3 and 6. The process of the invention is particularly suited to degrade polyethylene terephthalate, and polyethylene terephthalate containing material.