Pyrolysis experiments on n-hexadecane n-C were conducted at 673 แ 723 K and 16 n-C concentrations of 0.07 แ 1.47 molrL by using batch type reactors. The main prod-16 ucts of n-C pyrolysis were n-alkanes and 1-alkenes at all the reaction conditions. The 16 1-alkenern-alkane ratio decreased with increasing n-C concentration at all the reac-16 tion temperatures. The rate of n-C pyrolysis increased to a maximum and then de-16 creased with increasing n-C concentration. The actiยฎation energy of the oยฎerall rate 16 constant of n-C pyrolysis was 196 kJrmol at 0.07 molrL of n-C concentration and 16 16 263 kJrmol at 0.22 molrL. To describe these phenomena, a mathematical model for the pyrolysis that expresses the radical network reaction, including initiation, isomerization, โค -scission, H abstraction, and termination, was deยฎeloped. The effect of radical ( ) size on the rates of bimolecular reactions H abstraction and termination was important for a correct quantitatiยฎe description. Comparison between the experimental data and the model showed that the rates of bimolecular reactions were inยฎersely proportional to the carbon number i of radical R . The model can predict product distribution i ( ) and n-C pyrolysis rate in a wide range of temperatures 603 แ 893 K and n-C 16 16 ( y 3 ) concentrations 6.86 = 10 2.48 molrL . Furthermore, the model can describe the pyrolysis kinetics of n-C แ n-C by considering the carbon number of the hydrocar-10 25 bon.