Thermal catalytic cracking of naphtha over multi wall carbon nanotube catalysts

The effects of temperature and Fe loading over multi wall carbon nano tube catalysts in thermal catalytic cracking of naphtha to produce light olefins have been studied in this paper. The CCD method was utilized and a set of experiments were designed and carried out. The temperature and loading varied from 572 to 628 degrees C and 0.34 to 11.66 wt.% Fe, respectively. In order to determine the effects of the variation of the operating conditions on the yield distributions, a set of statistical models were utilized and the maximum point of the yield of each product was determined. The maximum yield of ethylene (18.84 wt.% of product) and propylene (12.85 wt.% of product) was obtained at 628 degrees C and 10.6 wt.% loading of Fe over CNTs. Finally, thermal cracking of naphtha was carried out and was compared with thermal catalytic cracking of naphtha. As a result, at 620 degrees C, the yield of ethylene and propylene in thermal-catalytic cracking was 6.3% and 4.7%, respectively, more than those in thermal cracking of naphtha. (C) 2012 Elsevier B.V. All rights reserved.