PYROLYSIS OF ETHANE AND PROPANE WITH ISOPARAFFINS ADDITIVE

The addition of isooctane and liquid isooctane fractions in small quantities (3%) induces the conversion increase of ethane and propane at moderate temperatures (750-800-degrees-C), effect which is reduced when these temperatures are higher. The rate constants are higher for copyrolysis in comparison with those values obtained in singular pyrolysis of ethane and propane. The decrease of yield in ethylene and the increase of yields in propylene and butenes, without affecting the yield in butadiene, is due to the higher potential in propylene of isoparaffins. The promoting effect of isoalkanes on pyrolysis is explained by the interference of the reactive species H. and CH3. which are consumed especially for the olefines decompsition (H.) and for the radical chain propagation (CH3.).