RSI PURIFIERS' RCP series of catalytic purifiers utilize a high surface area precious metal catalyst on a ceramic substrate. The catalyst promotes the combination of hydrogen and oxygen at ambient temperature to form water and provides close to complete elimination of one species in the presence of an excess of the other.
The process is exothermic and releases heat.
H2(g) + 1/2O2(g) --> H2O(g) + 242kJ/mol* (57kCal/mol)
At temperatures above ambient, depending on the feed stream, the catalyst can promote the methanation of carbon monoxide or carbon dioxide, the burning of hydrocarbons and other possibly unwanted side reactions. It is recommended that the factory be consulted about use of the RCP on unusual process streams.
Water condensation should be avoided. Liquids prevent contact between the process stream and the catalyst. If the process stream is operating near its' dew point, the RCP should be heated externally. Carbon monoxide interferes with the oxygen/hydrogen reaction. Elevated operating temperatures may be required when CO is present.
The precious metal catalyst is sensitive to poisoning by heavy metals (e.g. lead, mercury, cadmium), by sulphur compounds, by oils, organic solvents and chlorine compounds. Whenever there is doubt about the compatibility of individual process stream components with the RCP Purifier, it is recommended that the factory be consulted.
RCP catalysts are generally in the form of beads or pellets. Purifiers are intended for operation in a vertical position with the feed gas entering the top. Upflow may cause fluidization of the catalyst bed and attrition of the catalyst. Use in the horizontal position may cause settling and allow bypassing of the catalyst bed.
When circumstances require them, monolithic catalyst substrates can be specified on special order. Monolithic devices can be used in any orientation.
RSI can provide devices for removing oxygen from inert gas streams at ambient temperature. These devices are based on a highly active high surface non-precious metal catalyst that forms a reducible oxide. The capacity of these devices is limited by the amount of catalyst available in the catalyst bed and periodic regeneration is required. (Regeneration requires heating and back-flushing the catalyst bed in a reducing atmosphere.)
*kJoule/mol. 4.184 kJoule = 1 kCalorie