ABSTRACT
Catalysts are supplied in mild steel drums with polythene liners and depending on the catalyst concerned, the full drums weigh between 50 and 250 kg. Catalysts are sieved by the manufacturer before they are packed into drums for despatch, but in some instances attrition can occur in transit if the drums are roughly handled. Most catalysts produce some dust in the vessel during the charging process, and respiratory protection must be provided for anybody who has to enter at the time. Catalysts are designed to be in their active form under process conditions. Low-temperature shift catalysts are supplied as supported copper oxide, and require careful reduction to give the maximum activity. The operation of reforming catalysts is sometimes impaired by carbon deposition, usually as a consequence of maloperation. In most ammonia plants the shift catalyst does not reach full operating temperatures until air is put on the secondary reformer.
