Shorter synthetic routes Professional4 months ago - Mobile Phone & Tablets - Makoko - 56 views
Since greater cell density results in increased surface area, this means that a metal substrate of a given volume will be more catalytically active than a ceramic one. Most metal substrates used in the cooking and heating sectors have between 100 and 200 cells per square inch (cpsi). Metal substrates can be made in a variety of profiles, with round, square and rectangular being most common. Another variable is the pattern of the corrugations in the foil, which can either be straight through or involve changes of direction. The latter option is known as ‘herringbone’ and gives rise to turbulence which increases the activity of the catalytic converter but at the expense of an increased pressure drop.
There are various ways of making metal substrates but the top-quality versions utilize Fecralloy foil which consists of 74% iron, 21% chromium and 5% aluminium. The main advantage of Fecralloy is that, when heated in air, a layer of aluminium oxide forms on the surface which protects the iron from corrosion and also provides a good key for the catalytic coating. Therefore this type of metal substrate is hygienic enough to use in cooking appliances.
Except for this, there are also other kinds of Honeycomb Substrates such as Ceramic Honeycomb Substrate, Metallic Honeycomb Substrate, Ceramic Honeycomb Substrate Catalyst Carrier, etc. And the Honeycomb Substrates are always used as a carrier for catalyst in chemical reactions.