Variable Porosity Filter with Switching Material

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Solution Overview

Problem

Conventional filters have fixed pore sizes, making it necessary to replace the entire filter to change porosity, which is inefficient for applications requiring adjustable separation of substances.

Innovation Solution

A filter with variable porosity is developed, utilizing a porous base material with switching materials that change their spatial structure in response to external control interventions, allowing for adjustable permeability by altering the pore's cross-sectional area or mesh size, enabling selective filtration of substances.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If conventional filters with fixed pore sizes are used, then manufacturing and operation are simple, but the filter cannot adapt to different separation requirements and must be replaced to change porosity

Engineering Contradiction:
Improveadjustability of porosityVSAvoidfilter structure complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The filter incorporates switching material in the pores that can dynamically change its spatial structure and expansion in response to external control interventions (such as pH, temperature, or light changes). This dynamic behavior allows the pore permeability to be adjusted between open and closed states, enabling the filter to adapt its porosity according to different separation requirements without replacing the entire filter structure.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The invention changes the physical-chemical parameters of the filtering system by introducing switching material whose properties (spatial structure, expansion, mesh size) can be modified by external control interventions. This allows the same filter to exhibit different permeability characteristics under different conditions, achieving multiple separation functions with a single filter device.

Inventive Principle:
Principle #35Parameter changes

2Manufacturing precision

If multiple filters with different pore sizes are used to separate different substances, then separation precision is improved, but device complexity and the number of components increase

Engineering Contradiction:
Improveseparation precisionVSAvoidnumber of filters
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The filter is designed with multi-functionality by incorporating switching material that can respond to different external control interventions. A single filter can perform multiple separation functions by adjusting its pore permeability in response to different stimuli (pH changes, temperature changes, light exposure), eliminating the need for multiple specialized filters and reducing overall system complexity while maintaining high separation precision.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The dynamic switching capability allows one filter to replace multiple static filters. By controlling the switching material's expansion and contraction through external interventions, the same filter can selectively open or close pores to separate different substances based on size, charge, or other properties, achieving the separation precision of multiple filters with a single dynamic device.

Inventive Principle:
Principle #15Dynamics

3Manufacturing precision

If the entire filter is replaced to change pore size, then the correct pore size is achieved, but time and resource efficiency decrease

Engineering Contradiction:
Improvepore size accuracyVSAvoidfilter replacement time
Core Design Contradiction:
Manufacturing precisionVSLoss of time

Solution Approach 1:

Instead of replacing filters to change pore size, the invention uses switching material that can dynamically adjust pore permeability in response to external control interventions. This allows rapid switching between different effective pore sizes without any physical replacement, achieving the correct pore size accuracy instantaneously and eliminating the time and resource loss associated with filter replacement.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The invention changes the operational parameters of the filter by modifying the spatial structure and expansion of the switching material through external control interventions. This allows the same physical filter to achieve different effective pore sizes by changing its structural parameters, eliminating the need for replacement and significantly reducing time and resource consumption.

Inventive Principle:
Principle #35Parameter changes

4Adaptability or versatility

If switching material is introduced into pores to change permeability, then adaptability is improved, but manufacturing complexity increases

Engineering Contradiction:
Improvepermeability adjustabilityVSAvoidfilter production complexity
Core Design Contradiction:
Adaptability or versatilityVSEase of manufacture

Solution Approach 1:

The switching material is introduced into the pores during the filter manufacturing process itself, rather than as a separate post-processing step. The porous base material is prepared first, then the switching material is introduced into the pores while the structure is still accessible, and finally the structure is stabilized. This preliminary action simplifies manufacturing by combining multiple steps into an integrated process.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent uses an intermediary approach by introducing switching material through a controlled process that mediates between the porous base material and the final functional filter. The switching material acts as an intermediary component that can be selectively placed in pores and then activated or stabilized, providing a manageable manufacturing pathway that balances complexity with functional adaptability.

Inventive Principle:
Principle #24Intermediary (Mediator)

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

Enables quantitative and qualitative changes in filtration, allowing for more efficient separation of substances by adjusting permeability, reducing the need for multiple filters and improving fractionation of mixtures, while maintaining high throughput and stability.

Implementation Method 1

a switching material is arranged in each of the pores, which is able to change its spatial structure and/or expansion in response to an external control intervention and thus convert the control intervention into a change in the permeability of the pore

Methodology Applied
Scientific EffectSwelling: Hydrogel

Implementation Method 2

The permeability of a pore can be changed by narrowing or expanding its continuous cross-section, i.e. a larger or smaller proportion of its cross-sectional area is occupied by the switching material

Methodology Applied
Scientific EffectPhase change: Phase Change

Implementation Method 3

If the switching material is spherical and swells in volume, it occupies a larger proportion of the cross-sectional area of the pore and the pore becomes less permeable

Methodology Applied
Scientific EffectVolume expansion: Thermal Expansion

Implementation Method 4

The permeability of a pore for a specific substance to be filtered can also be changed by increasing or decreasing the mesh size of a cross-linked structure made of the switching material. If the mesh size is larger than the atoms or molecules of the substance to be filtered, it can pass through the pore, otherwise not

Methodology Applied
Scientific EffectMesh size change: Nanoporous Material

Data Source

PatentEP3033162B1Filter having a variable porosity and method for producing the same
Publication Date: 2020.03.25 FORSCHUNGSZENTRUM JULICH GMBH
  • EP3033162B1 patent drawingFigure 1a
  • EP3033162B1 patent drawingFigure 1b
  • EP3033162B1 patent drawingFigure 2

AI summary

The invention relates to a filter having a variable porosity. Said filter comprises a porous base material having a plurality of continuous pores. According to the invention, a switching material is arranged in each of the pores, which switching material is able to change the spatial structure and/or expansion thereof upon an external control intervention, thus converting the control intervention to a change in the permeability of the pore. It has been identified that the permeability of the filter for certain materials can be altered quantitatively by way of the external control intervention. On the other hand, the permeability of the filter can also be altered qualitatively in the sense that a material, which previously could penetrate the filter, is no longer able to do so after the external control intervention. Conversely, by means of one and the same filter according to the invention, the permeability thereof is increased step by step from smaller to bigger materials, a mix of many variably sized components can be fractionated into the constituents thereof. In the scope of the invention, a method for producing the filter according to the invention was also developed. According to the invention, in this method, the switching material is introduced into the pores of the porous base material in a solvent, and subsequently, the solvent is vaporized. It has been identified that in this way, the switching material can also be introduced into a large number of pores simultaneously in a self-organized manner.