Green chemical production based on thermal cracking of inedible vegetable oil

Abstract

This work evaluated the process for heptaldehyde, undecylenic acid and methyl undecenoate production from castor oil, methyl ester of castor oil and ricinoleic acid. Experiments were performed in a continuous pilot-plant scale pyrolysis reactor. Those are very important green chemical products that might be obtained by the thermal cracking of castor oil. Transesterification of castor oil produces methyl ricinoleate and its thermal cracking generates methyl undecenoate and heptaldehyde. The pyrolysis temperatures tested were 530, 545, 560, and 575 ?C, with residence time from 17 to 32 s and mass flow at 400 g/h of the mixture of materials with 25% distilled water. It was observed that the temperature influence in relation to bio-oil generated and their differences for each material. The bio-oil was characterized by iodine index, acid number, mass, and the contents of its compounds were obtained by GC-FID chromatography. The best result for the undecylenic acid mass yield of the desired compounds occurred at 530?C, achieving 17.8 % from ricinoleic acid and 16.5% from castor oil. For the heptaldehyde the highest production was also obtained at 530 ?C, with a value of 20.7% from methyl ester and 15.2% from ricinoleic acid.