Ethyl propionate, pyrolysis

Pyrolysis of Carboxylic Acid Esters. The second stage of our proposed ethylene/propylene synthesis (eq. 21) has been demonstrated also for typical intermediate ethyl/propyl esters. Pyrolysis of acyclic, aliphatic carboxylic acid esters to alkenes and the parent acid is well documented (72-74) and in our work C1-C3 alkyl propionates, prepared by the synthesis techniques of Table VI (expt. 1 and 11) and isolated by fractional distillation, were pyrolyzed to ethylene, propylene and propionic acid by the homogeneous gas phase method (see Table VIII). In the initial experimental series, 98+% ethyl propionate is passed over pyrex helices at 460 C (expt. 16). Ethyl propionate conversion averages ca. 30% per pass selectivity to propionic acid is 95-97% ethylene comprises 92% of the light gas fractions. 

Pyrolysis of the crude Ci-C3 alkyl propionate distillate fraction from Table VI, expt. 1 yields ethylene, propylene and propionic acid as the principal products (see Table VIII, expt. 17) where the ethyl and propyl propionate conversions are 53 and 41%, respectively. The methyl propionate passes through the thermolysis unit unchanged. 

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