Economics of Catalyst Use

Cobalt boride has been used for reducing unsaturated aldehydes to unsaturated alcohols improved results are obtained by addition of ferric chloride or chromium chloride (6S). It is a low-activity catalyst. 

When hydrogenation reactions cease to be experimental and enter the stage of industrial development, the cost of the hydrogenation process becomes important. Some of the factors that enter into the determination of this cost are considered here. 

Determination of the actual cost of a hydrogenation process is difficult. Among the factors entering into the determination are catalyst cost, catalyst life, cost of materials, capital investment, actual yield, space-time yield, and purification costs, Considerable data are needed to make an accurate evaluation. 

The purchase price of an initial charge of catalyst is but one factor entering into the cost of using a catalyst. For noble-metal catalysts, which have high reclaim value, this price is in itself relatively unimportant. The number of greater significance is the cost of the catalyst in use, that is, the cost of the catalyst when the value of reclaimed metal has been deducted, 

Eventually all catalysts become spent. At this stage they can be discarded, itself sometimes a problem, or returned to a refiner for recovery of metal values. In commercial use, noble-metal catalysts are always returned to a refiner. At the refinery, the catalyst is destroyed and the noble metals are recovered and converted to high-purity metal. In a loop system, the pure metal is converted to a suitable salt and again used for catalyst manufacture. In the entire loop, some metal will be lost and must be replaced with fresh metal. Refining is nowadays very efficient, and most metal loss will occur in the process itself, The total cost of a catalyst used in a loop is accordingly given by  

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