Suppliers nickel hydrogen

Catalyst Type - Nickel metal catalyst, sometimes promoted with copper, aluminum oxide, or sulfur, are commonly used in commercial hydrogenation. These catalysts are prepared by a variety of techniques, some proprietary to the catalyst supplier, to provide the surface activity necessary for the desired selectivity. Precious metals have been found to be effective hydrogenation catalysts, which are more active at lower temperatures and produce less trans-isomers. However, their use has been deterred by the initial cost and recovery problems associated with the minute quantities required. 

Coca-Cola [101] describe a process for reducing acetaldehyde evolution from PET by adding a hydrogen supplier, preferably poly(methylhydro)siloxane and a hydrogenation catalyst such as nickel or palladium. The additives are slurried in oil, coated on PET pellets, and the resultant material extruded. 

Careful specification of purity, unallowable impvuities, fabrication method, post-fabrication treatments, packaging, etc. of the source materials purchased can be important in obtaining a reproducible process. Using inexpensive material or material of unknown origin often creates problems. Often impurities such as O, N, C, and H are not specified by the supplier and they may be present in significant quantities. Examples of unspecified impurities are oxidized surfaces of reactive metals, hydrogen incorporated in electrorefined chromium, carbon monoxide in nickel purified by the carbonyl process, and helium in natural quartz. Generally it is better to specify vacuum-melted materials from the supplier when possible. 

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