Properties of the coated metal support:

• Good adhesion of the coating to the metal support. That allows to perform mechanical treatment - cutting, corrugation, twisting, rolling etc. after spraying without peeling of the sprayed layer (Fig.2);
• High thermal and electrical conductivity that gives an opportunity to change construction of the reactor to more efficient and heat catalytic block by electric current;
• Low weight compared to the most of ceramic substrates used for analogical purposes;
• High specific surface area of the coating compared to others metal based ceramic coatings - usually 70-80 m²/g but can reach up to hundreds of m²/g (Fig.3);
• Good resistance to mechanical and thermo shock;
• High thermal conductivity (22.9 W/(mºC) at 800ºC) due to metal strip support; 

 

 

 

Fig.2. Flat and corrugated samples

 

 

 

 

 

The base Amiagus thermal coating technology opens new ways for creating various catalytic coatings on different kinds of metal strips for wide range of applications:

• metal based catalysts for tar cracking
• metal based catalysts for hydrocarbon reforming
• rolled metal strip coated with catalytic support on one or both sides 

Coated metal support is used to form metal based catalytic element with honeycomb structure. It is produced by rolling two both sides coated metal strips – one flat and one corrugated (refer to Fig.4), around a transversal axis.


Technological steps

 

Catalytic blocks are made in these technological steps:

1. Deposition of coating by thermal spraying of ceramic based catalytic powders on both sides of metal strip (basically of 0.03-0.05 mm thickness and 45-100 mm width).
2. One part of coated strip is being corrugated. One of the advantages of our technology – high adhesion of coated layer to the metal strip that allows us to perform corrugation without peeling of the coated layer.
3. Formation of cylinder shaped catalytic block with honeycomb structure that consist of two rolled metal strips, flat and corrugated (Fig. 5 A-D). Block can be of any height (basically 45-100mm) and diameter of up to 200 mm and more.

Using our technology we are able to produce catalytic element with axial and/or radial gas transfer and longitudinal channels of triangular shape in cross-section. Catalytic element is shown on the Fig.5C. The diameter of the element depends on internal diameter of the tube, or other vessel used. The element in cross-section can be adjusted to oval or even rectangular shape.

 

 

 

 Fig.5A-D. Honeycomb structure catalytic element
 

 

• Effective properties of formed metal based catalytic block:
• Good adhesion of coated layer to metal substrate;
• Good resistance to thermal cycling and gas erosion;
• Low back pressure due to honeycomb structure and metal strip thickness;
• Low weight compared to most of ceramic pellets used for analogical purposes; 
• About 10 times higher geometrical surface area of honeycomb catalytic unit compared to the same volume of ceramic pellets used for steam reforming process;
• High 22.9 W/(mºC) thermal conductivity at 800ºC due to metal strip support;
• Good metal support electrical conductivity that gives an opportunity to heat catalytic block by electric current;

 

 

Cooperation