Ammonia manufacture reactor types

Not all catalysts need the extended smface provided by a porous structure, however. Some are sufficiently active so that the effort required to create a porous catalyst would be wasted. For such situations one type of catalyst is the monolithic catalyst. Monolithic catalysts are normally encountered in processes where pressure drop and heat removal are major considerations. Typical examples include the platinum gauze reactor used in the ammonia oxidation portion of nitric acid manufacture and catalytic converters used to oxidize pollutants in automobile exhaust. They can be porous (honeycomb) or non-porous (wire gauze). A photograph of a automotive catalytic converter is shown in Figure CD 11-2. Platinum is a primary catalytic material in the monolith. 

The property of f. to be local irritants of eyes and skin is reduced by ethoxylation. Manufacturing from RR is predominantly done via the fatty nitriles, which are made from fatty acids by reaction with ammonia. The nitriles are reduced by - hydrogenation (batch or continuous) into amines. The reaction conditions determine whether primary, secondary or tertiary amines result. Saturated f are formed when nitriles are hydrogenated at 80-140 °C and 1-4 MPa/lO O bar over Ni catalyst. Unsaturated f can be obtained with Raney Co or Cu-chromite as catalyst. Ammonia has to be present to suppress the formation of secondary amines. Saturated and unsaturated secondary amines are gained in yields of more than 90% if ammonia is vented from the reactor, the reaction temperature is 160-210 °C, and pressure is maintained at 5-10 MPa/50-100 bar. Trialkylamines are produced via the imine R-CH=NH and Schiff base R-CH=N-CH3 with Ni catalyst at 230 °C and 0.7 MPa/7 bar hydrogen pressure. Important amine types, which are the base for making dimethyl dialkyl ammonium compounds, are made by the following reaction ... 

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