Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Holding material for catalytic converter and method for producing the same

a technology of catalytic converter and holding material, which is applied in the direction of machines/engines, mechanical equipment, separation processes, etc., can solve the problems of alumina fiber mat, surface pressure is slightly reduced in comparison with other fiber mats in equal density, and the temperature of not less than 600.degree. c of ceramic fiber ma

Inactive Publication Date: 2003-10-02
NICHIAS CORP
View PDF2 Cites 34 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

[0016] In the holding material according to the invention, because the aluminum fiber mat excellent in heat resistance is disposed on a high-temperature side to come into contact with the catalyst carrier, the deterioration of the mullite fiber mat with the elapsed time can be suppressed so that high surface pressure due to the mullite fiber mat can be kept for a long term.
[0020] In the holding material according to the invention, a mixture of alumina fiber excellent in heat resistance and mullite fiber capable of being expected to have high surface pressure is used so that surface pressure sufficient to hold the catalyst carrier can be kept for a long term.

Problems solved by technology

The ceramic fiber mat however has a problem that the ceramic fiber mat cannot be used at a temperature of not lower than 600.degree. C.
On the other hand, the alumina fiber mat has a disadvantage in that surface pressure is slightly reduced in comparison with other fiber mats in equal density.
Accordingly, the cost increases because it is necessary to increase the density in order to increase the surface pressure.
On the other hand, the mullite fiber mat however has a disadvantage in that the mullite fiber mat deteriorates with the elapsed time because the decreasing rate of elastic recovery is high when heat stress is repeatedly applied on the mullite fiber mat.
The present situation is that no measure can be taken in the related art against rising of the temperature in use of the catalytic converter.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Holding material for catalytic converter and method for producing the same
  • Holding material for catalytic converter and method for producing the same

Examples

Experimental program
Comparison scheme
Effect test

example 1

[0036] Into water, 97 parts by weight of alumina fiber of low crystallinity containing 96% by weight of Al.sub.2O.sub.3 (and SiO.sub.2 as a residual component) and having a fiber size of about 4 .mu.m and a fiber length of about 3 mm, and 5 parts by weight of an organic binder (acrylic emulsion) were dispersed to prepare an alumina fiber-containing aqueous slurry. On the other hand, 97 parts by weight of mullite fiber of low crystallinity containing 80% by weight of Al.sub.2O.sub.3 (and SiO.sub.2 as a residual component) and having a fiber size of about 4 .mu.m and a fiber length of about 3 mm, and 3 parts by weight of an organic binder (acrylic emulsion) were dispersed into water to prepare a mullite fiber-containing aqueous slurry.

[0037] First, the alumina fiber-containing aqueous slurry was molded by suction dehydration and dried to produce an alumina fiber mat having grammage (areal density) of 400 g / m.sup.2. Then, the mullite fiber-containing aqueous slurry was applied on one s...

second embodiment

[0045] Second Embodiment

[0046] FIG. 2 is a sectional view schematically showing a catalytic converter provided with a holding material according to a second embodiment of the invention. The configuration of the catalytic converter is the same as that of a related-art catalytic converter except that the holding material 3 according to the invention is constituted by a mixture of alumina fiber and mullite fiber.

[0047] The holding material 3 can be shaped like a flat mat. When the holding material 3 is molded into a shape according to the contour shape (e.g., cylindrical shape in FIG. 2) of a catalyst carrier 1, the holding material 3 can be directly mounted on the catalyst carrier 1 to facilitate production of the catalytic converter.

[0048] Materials suitably selected from known materials heretofore used in a holding material can be used as the alumina fiber and the mullite fiber. The material preferably used as the alumina fiber is fiber containing 90% by weight or more of Al.sub.2O....

example of second embodiment

[0061] The invention will be described below more specifically in connection with the following Examples and Comparative Examples but the invention is not limited thereto at all.

[0062] Alumina fiber of low crystallinity containing 96% by weight of Al.sub.2O.sub.3 (and SiO.sub.2 as a residual component) and having a mean fiber size of about 3 .mu.m and a wet volume of 800 cc / 5 g was mixed with mullite fiber of low crystallinity containing 80% by weight of Al.sub.2O.sub.3 (and SiO.sub.2 as a residual component) and having a mean fiber size of about 4 .mu.m and a wet volume of 800 cc / 5 g while the mixture ratio (weight ratio) of alumina fiber to mullite fiber was changed variously to (1) 100% of alumina fiber, (2) 75% of alumina fiber and 25% of mullite fiber, (3) 50% of alumina fiber and 50% of mullite fiber, (4) 25% of alumina fiber and 75% of mullite fiber, and (5) 100% of mullite fiber. With respect to 100 parts by weight of each of the thus obtained mixtures, 8 parts, by weight of...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
Fractionaaaaaaaaaa
Fractionaaaaaaaaaa
Surface pressureaaaaaaaaaa
Login to View More

Abstract

A holding material for a catalytic converter is interposed in a gap between a catalyst carrier and a metal casing receiving the catalyst carrier. The holding material includes a mat including alumina fiber and mullite fiber, wherein the alumina fiber and the mullite fiber are unitarily collected to form the holding material having a predetermined thickness.

Description

[0001] 1. Field of the Invention[0002] The present invention relates to a holding material for a catalytic converter, for example, for purging exhaust gas emitted from an automobile, and a method for producing the holding material for the catalytic converter.[0003] 2. Description of the Related Art[0004] As known commonly, a catalytic converter for purging exhaust gas is mounted in a vehicle such as an automobile in order to remove detrimental components such as carbon monoxide, hydrocarbon, and nitrogen oxides from exhaust gas emitted from an engine of the vehicle. Generally, as shown in FIG. 2 which is a sectional view, the catalytic converter has a catalyst carrier 1 shaped like a cylinder, a metal casing 2 for receiving the catalyst carrier 1, and a holding material 3 interposed in a gap between the catalyst carrier 1 and the casing 2 while mounted on the catalyst carrier 1.[0005] Generally, the catalyst carrier 1 has a cylindrical honey-comb molded material, for example, made o...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): F01N3/28
CPCB32B18/00C04B2237/76C04B2235/5224C04B2235/5228C04B2235/526C04B2235/5264C04B2237/38F01N3/2853F01N3/2864C04B35/632C04B35/63424C04B2235/656C04B2237/341C04B2237/343C04B2237/50C04B2237/704C04B35/80C04B35/82C04B2235/5232
Inventor ANJI, TOSHIYUKITANAKA, MASAFUMISAKANE, TADASHIMOCHIDA, TAKAHITO
Owner NICHIAS CORP
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com