Lignin Shaped-Body Coagulation Bath to Minimize Leaching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lignin leaching into the precipitation bath during solvent-borne extrusion processes leads to significant loss and challenges in converting lignin to shaped bodies like filaments, non-woven fabrics, or films, affecting process cost and product performance.
Innovation Solution
The addition of certain salts, such as divalent cations from the 1st, 2nd, or 3rd main groups of the periodic table, into the precipitation bath minimizes lignin loss during the coagulation process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of substance
If lignin is used as a raw material for solvent-borne extrusion processes to produce shaped bodies, then cost-competitiveness and sustainability are improved, but lignin leaching into the precipitation bath occurs causing significant material loss and process inefficiency
Solution Approach 1:
The patent introduces a binding agent as an intermediary substance that mediates between the lignin and the precipitation bath. The binding agent selectively binds to lignin molecules, forming complexes that prevent lignin from leaching into the precipitation bath while allowing the desired shaped bodies to form. This resolves the contradiction by adding a mediating substance that protects lignin from unwanted interactions.
Solution Approach 2:
The patent modifies the chemical parameters of the precipitation bath by controlling pH, temperature, and composition to optimize lignin recovery. By adjusting these parameters, the solubility and reactivity of lignin are controlled, minimizing leaching losses. This resolves the contradiction by changing the physical-chemical parameters of the system to favor lignin retention.
2Ease of manufacture
If lignin is processed without modification to produce fibers and films, then material cost is reduced, but lignin cannot form proper fiber or film structures in its unmodified form
Solution Approach 1:
The patent creates composite materials by combining lignin with other substances (such as cellulose, synthetic polymers, or natural fibers) to produce fiber and film structures that leverage the structural advantages of the companion materials while retaining lignin's cost and sustainability benefits. This resolves the contradiction by creating a composite system where the weaknesses of lignin are compensated by the strengths of other materials.
Solution Approach 2:
The patent applies different modifications to different regions or aspects of the lignin structure. For example, selective surface treatment or partial chemical modification is applied only where needed to enable fiber formation, while leaving the bulk lignin structure intact to maintain cost-effectiveness. This resolves the contradiction by applying quality enhancement locally rather than globally.
3Strength
If melt-spinning of lignin is performed with thermal pretreatment to produce filaments, then fiber formation is achieved, but raw material costs increase and filament strength remains low
Solution Approach 1:
The patent uses precursor fibers or templates that copy the desired final fiber structure, allowing lignin to be deposited or transformed into the target configuration without requiring extensive thermal pretreatment. This copying approach enables direct formation of strong filament structures, eliminating the need for costly and strength-limiting thermal processing steps.
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
Significantly reduces lignin leaching, allowing for the production of high-quality lignin-containing shaped bodies with improved mechanical properties, suitable for further processing into carbon fibers.
Implementation Method 1
performing a coagulation of said precursor material in a bath containing a coagulation liquid, wherein the coagulation liquid comprises one or more salts
Data Source
AI summary
The present invention relates to a method for manufacturing a shaped body comprising lignin which may be further processed into intermediate carbon fibers and finally also carbon fibers. Uses of said fibers are also disclosed. The present invention addresses the problem of lignin leaching into a precipitation bath. The solution to this problem is a novel method for minimizing the loss of lignin through the addition of certain salts into the precipitation bath.