Production of hydrocarbons by pyrolysis of methyl esters from rapeseed oil

The pyrolysis of a mixture of methyl esters from rapeseed oil has been studied in a tubular reactor between 550 and 850°C and in dilution with nitrogen. A specific device for the condensation of cracking effluents was used for the fractionated recovery of liquid and gaseous effluents, which were analyzed on‐line by an infrared analyzer and by gas chromatography. The cracking products in the liquid effluent were identified by gas chromatography/mass spectrometry coupling. The effects of temperature on the cracking reaction were studied for a constant residence time of 320 ms and a constant dilution rate of 13 moles of nitrogen/mole of feedstock. The principal products observed were linear 1‐olefins,n‐paraffins, and unsaturated methyl esters. The gas fraction also contained CO, CO2, and H2. The middle‐chain olefins (C10–C14 cut) and short‐chain unsaturated esters, produced with a high added value, had an optimum yield at a cracking temperature of 700°C.