A promising route for processing hazelnut Shell is pyrolysis, which has been conducted tinder a variety of experimental conditions resulting irt the production of char; a tarry material, an aqueous fraction and gaseous products. It is neccessary to understand the kinetics of pyrolysis in order to design a suitable pyrolysis reactor: Temperature and heating rate both strongly affect the pyrolysis products and kinetic parameters. The influence of the main reaction parameters, such as temperature, particle size, catalyst and heating rate, on the yields from pyrolysis has been studied and the results are illustrated and analyzed. The effect Of a catalyst (K2CO3) on the yield of pyrolysis was slight. The kinetic parameters of activation energy, the pyrolysis rate constant, and order of reaction are given in this paper: (C) 1998 Elsevier Science Ltd. All rights reserved.