Monolithic Catalyst Vs Ceramic Honeycomb

The flow pattern in the monolithic catalyst reactor was segmented gas liquid flow slug flow.

Monolithic catalyst vs ceramic honeycomb.

The catalyst support of the present invention is formed of ceramic such as cordierite of which coefficient of thermal expansion is lower than alumina and is provided with microcracks which occur when the honeycomb structure is formed. Honeycombs and foams william m carty and peter w lednor recent advances have been made in research on ceramic monolithic catalyst supports particularly on honeycombs and ceramic foams. In the off road emission control applications monolithic metallic or ceramic catalyst supports became the standard. Monoliths are sometimes called flow through substrates.

Monolithic ceramics and heterogeneous catalysts. The hydrogen pressure and the temperature were varied between 30 40 bar and 509 523 k respectively. Application areas in which monolithic catalysts have superior performance. Today almost all automobiles are equipped with either ceramic or metallic honeycomb supported catalysts.

Automotive oem s predominately utilize these parts due to their lower component costs. Monolithic catalyst substrates figure 1 are made of ceramics or metal. In the processes of the chemical industry however their current use is very limited. Metallic vs ceramic catalyst substrates.

Many coating companies will suggest ceramic to avoid production. In this paper the current status of the monolith technology for applications in the chemical industry is reviewed. Other channel cross sections are possible including triangular hexagonal trapezoidal and round. Each monolith contains thousands of parallel channels or holes which are defined by many thin walls in a honeycomb structure the channels can be square hexagonal round or other shapes.

Ceramic substrates honeycombs usually have square cells while most metallic substrates have sinusoidal channels. Monoliths for automotive catalytic converters are made of a ceramic that contains a large proportion of synthetic cordierite 2mgo 2al 2 o 3 5sio 2 which has a low coefficient of thermal expansion. A catalyst support provided with an activated alumina layer which is formed on the surface of the ceramic honeycomb structure is disclosed. Monolithic catalyst supports are honeycomb structures with many small cells or parallel channels that allow exhaust gases to run axially through the catalyst.

Honeycomb shaped monolithic catalysts are the standard catalyst shape in most environmental applications. The pelleted design is obsolete and increasingly difficult to find on the market. Ceramic substrates have been the choice for catalyst coating companies for decades.