Propanol, propionaldehyde propanal and propionic propanoic acid

6 n-Propanol, propionaldehyde (propanal) and propionic propanoic) acid 

Historically, these materials had modest outlets, e.g. in speciality solvents or as intermediates for polyols, agricultural chemicals, etc. From the late 1980s, BP established the use of propionic acid as a grain preservative, now of major importance in Europe, to utilize the significant quantities coproduced in naphtha oxidation. 

In the U.S.A., all these materials are produced via the hydroformylation of ethylene. Union Carbide chose the rhodium/phosphine catalyst system for their early 1980s expansion (and another planned) older plants use cobalt catalysts. 

C2H5CH2OH C2H5C02H n-(l-) Propanol Propionic (Propanoic) Acid 

Growing use of propionic acid as a preservative in the U.S. required some 40% of the 90 kt produced in 1993. 

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