Environmentally benign manufacturing of fine and intermediate chemicals

Environmental concerns and regulations are getting more and more severe. A lot of efforts and progress have been accomplished in the environmentally benign and sustainable industrial manufacture of fine and intermediate chemicals in recent years. Solid acid-base catalyzed commercialized processes as well as heterogeneously catalyzed oxidation processes and a dehydrogenation process are reviewed. The examples for acid catalyzed processes are the BASF-tert.-butylamine-process and the Beckmann-rearrangment to form epsilon -caprolactam. For solid base catalyzed processes, the Sumitomo-process for the production of 5-ethylidene-bicyclo [2.2.1] hepta-2-ene and other double bond isomerization processes have been chosen. In addition, short comments are given on side chain alkylation and transesterification reactions. Acid-base bifunctional heterogeneous catalysts are employed for the hydrogenation of aromatic and aliphatic carboxlic acids to the corresponding aldehydes. In oxidation processes, the oxidation of an unsaturated alcohol to the corresponding aldehyde will be demonstrated on the BASF-citral-process in which a silver catalyst is applied. For the oxidation of alkylaromatic compounds to the corresponding acids, the oxidation of beta -picoline to nicotic acid in the presence of V2O5/TiO2-catalyst will be discussed. The oxidation of benzene to phenol using N2O as oxidant over a MFI-type zeolite is also described. The dehydrogenation of alpha -limonene to p-cymene over Pd/SiO2 catalyst is selected as an example for the environmentally benign use for a renewable feedstock. (C) 2000 Elsevier Science B.V. All rights reserved.