The aerial oxidation of scottish shale wax

✍ Scribed by Pettet, A. E. J. ;Greaves, W. S.

• Publisher: Wiley (John Wiley & Sons)
• Year: 1947
• Weight: 490 KB
• Volume: 66
• Category: Article
• ISSN: 0368-4075
• DOI: 10.1002/jctb.5000660406

✦ Synopsis

Abstract

In the aerial oxidation of Scottish shale wax a satisfactory rate of oxidation was attained by oxidising a mixture of 60% fresh wax with 40% unsaponifiable material from previous runs, at a temperature of 110°. Air for oxidation at the rate of 4 cu. ft./hour/100 g. mixture, was best introduced in a finely divided state by means of a ceramic filter block, and either cobalt or manganese oleate at 1% concentration provided a satisfactory catalyst, with a slight advantage in favour of the former. An aluminium apparatus was preferable to one of glass, since the considerable induction period evident in the latter was eliminated when aluminium was used. Adequate space had to be provided in the reaction chamber, for formation of froth, as well as a subsidiary chamber for subsequent froth breaking. With the manganese catalyst in presence of unsaponified material, the yield of C~10~‐C~20~ acids rose from 7% when the reaction was taken to an acid number of 36 to 27% at acid number 186. The acetyl number of the final acids also tended to rise when the oxidation was carried to a high acid number but the precise point was not determined at which the oxidation should be stopped so as to give the best results, having regard to both quantity and quality of acids. The wax could be almost completely oxidised, but no advantage was thereby gained.