Laporte Industries Limited

Francis Robert Hardy

Ian Robert King

Brian Keith Howe

Douglas Alfred Clarke

In the oxidation of .alpha., .beta.-diols to .alpha., .beta.-diones with oxygen, the use of a catalyst comprising at least one metal selected from Cu, Ag and Au and at least one element selected from Ge, Sn, Pb, N, P, As, Sb, Bi. In the oxidation of ethylene glycol to glyoxal with oxygen, condensing ethylene glycol from the products from the reactor and thereafter lowering the temperature to condense the glyoxal. A purification process for glyoxal uses a weakly basic anion exchange resin.

Vapour phase oxidation process

A .delta.- or .epsilon.- lactone is heated in the vapour phase and the presence of a cracking catalyst to form a monounsaturated acyclic carboxylic acid. For example .epsilon.-caprolactone gives .delta. - .epsilon. hexenoic acid. This acid is then cyclised by heating with a strong protonating agent. In the example the product is .gamma.-caprolactone or 4-hexanolactone.

Lactones

A feed material containing the group --O--(CR.sub.2).sub.n --CO-- in a macrocyclic ring or acylic chain is heated to between 300.degree.C and 500.degree.C in the absence of a catalyst to give a mono-unsaturated acyclic carboxylic acid. For example polymeric .epsilon.-caprolactone gives .delta.-.epsilon. hexenoic acid. This acid is then cyclised by heating with a strong protonating agent. In the example the product is .gamma.-caprolactone or 4-hexanolactone.

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Luton, United Kingdom

Francis Robert Hardy