Triethylamine was found to be effective in promoting the cracking of heptane at the temperature of 550-650 degrees C. The experimental yields of ethylene and propylene are more than twice as high as the calculated values on hypothesis of no interaction between triethylamine and heptane, when the mass fraction reaches 6% at the most notable temperature of 550 degrees C. The accelerating mechanism is studied by gas chromatography-mass spectrometry (GC-MS) and it shows that the accelerating effect is mainly attributed to the initiative release of center dot CH3CH2 from triethylamine by the scission of the C-N bond. (c) 2006 Elsevier Ltd. All rights reserved.