Supercritical thermal decompositions of normal- and iso-dodecane in tubular reactor

Abstract

Thermal decompositions of a serials of normal- and iso-dodecane mixtures with different iso/ normal ratios were performed in a tubular reactor under supercritical conditions (550–680 °C, 4.0 MPa). It was found that iso-dodecane has an accelerating effect on the pyrolysis of n-dodecane depending upon iso/ normal ratio of the mixture, and that accelerating factor reaches up to almost 4 at iso/ normal ratio of 3/1. Decomposition conversions of the mixtures show a strong dependence on the iso/ normal ratio and the temperature owing to their possible effect on the radical generation mechanism and the decomposition kinetics. In addition, iso/ normal ratio of the mixture also affects the formation rates and morphologies of cokes due to the variation of decomposition conversion.