Wall Flow Catalyst with Internal Layer for PM Trapping

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing wall flow type exhaust gas cleaning catalysts face reduced gas permeability and inadequate PM trapping performance due to the configuration of catalyst layers, leading to uneven gas flow and underutilization of pores in dividing walls.

Innovation Solution

A wall flow type exhaust gas cleaning catalyst with a substrate having an entry side cell and an exit side cell divided by a porous dividing wall, where a first catalyst layer is disposed internally to contact the exit side cell and not the entry side cell, and a second catalyst layer is disposed on the surface to contact the exit side cell, optimizing gas flow and PM trapping.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If a first catalyst layer is provided in an internal portion of the dividing wall in contact with the entry side cell, then harmful component cleaning performance is improved, but gas permeability is reduced and PM trapping performance deteriorates

Engineering Contradiction:

Improveharmful component cleaning performanceVSAvoidgas permeability

Core Design Contradiction:

Object-affected harmful factorsVSQuantity of substance

Solution Approach 1:

The patent applies local quality by providing catalyst layers only in specific regions of the dividing wall (internal portions contacting entry and exit cells) while leaving other regions (surface portions) without catalyst layers. This localized catalyst distribution optimizes both harmful component cleaning in catalyzed regions and gas permeability in non-catalyzed regions, resolving the contradiction between cleaning performance and gas flow.

Inventive Principle:

Principle #3Local quality

2Object-affected harmful factors

If a first catalyst layer is provided in the dividing wall, then harmful component cleaning is improved, but gas flow becomes uneven and PM trapping performance deteriorates

Engineering Contradiction:

Improveharmful component cleaningVSAvoidgas flow uniformity

Core Design Contradiction:

Object-affected harmful factorsVSStability of the object's composition

Solution Approach 1:

The patent creates different functional zones within the dividing wall: catalyzed internal portions for harmful component cleaning and non-catalyzed surface portions for maintaining uniform gas flow and PM trapping. This local differentiation resolves the contradiction between cleaning performance and flow uniformity.

Inventive Principle:

Principle #3Local quality

3Object-affected harmful factors

If catalyst layers are provided in internal portions of the dividing wall, then harmful component elimination is improved, but pores in internal portions are not sufficiently used for PM trapping

Engineering Contradiction:

Improveharmful component eliminationVSAvoidPM trapping capacity

Core Design Contradiction:

Object-affected harmful factorsVSQuantity of substance

Solution Approach 1:

The patent assigns different functions to different regions: internal portions with catalyst layers handle harmful component elimination, while surface portions without catalyst layers handle PM trapping. This spatial functional differentiation resolves the contradiction between elimination performance and trapping capacity.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The dividing wall is segmented into multiple functional regions (catalyzed internal portions and non-catalyzed surface portions) that perform different functions. This segmentation allows simultaneous optimization of harmful component elimination and PM trapping without mutual interference.

Inventive Principle:

Principle #1Segmentation

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 configuration enhances PM trapping performance by ensuring uniform gas flow and effective utilization of pores, improving the overall exhaust gas cleaning efficiency and balancing PM trapping and gas cleaning performance.

Implementation Method 1

PM is trapped in pores at the surface of dividing walls and in internal portions of dividing walls as an exhaust gas passes through dividing walls

Methodology Applied

Scientific EffectPhysical filtration: Filter (physical)

Implementation Method 2

harmful components are eliminated as the exhaust gas passes through the catalyst layer

Methodology Applied

Scientific EffectCatalysis: Catalysis

Data Source

PatentUS10934910B2Exhaust gas cleaning catalyst

Publication Date: 2021.03.02 CATALER CORP

AI summary

An exhaust gas cleaning catalyst that has: a substrate having a wall flow structure, wherein an entry side cell, in which the end part on an exhaust gas inflow side is open, and an exit side cell, in which the end part on the exhaust gas outflow side is open, are divided by a porous dividing wall; and a first catalyst layer that includes a metal catalyst and is disposed within the dividing wall so as to be in contact with the exit side cell and not in contact with the entry side cell, and no catalyst layer is provided in the region in contact with the entry side cell.