General Comments
Hydrogenation is a hazardous operation with the gas being highly flammable and capable of forming explosive mixtures with air. In addition, most hydrogenation reactions are carried out using flammable organic solvents with many of the heterogeneous active metal catalysts employed being pyrophoric in the presence of air. Currently the majority of large scale hydrogenations are carried out in batch (utilizing equipment specifically designed for this purpose), though a significant amount of recent attention has focused on the use of continuous flow chemistry to help reduce the overall risk through minimization of the active reaction volume at any one time. Also, in situ continuous reaction monitoring (PAT) to determine extent of conversion removes the requirement for time consuming multiple batch sampling during the hydrogenation process.
Key References
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