KINETIC CHARACTERISTICS OF THERMOLYSIS PROCESSES OF WASTE RUBBER PRODUCTS

Abstract

In this paper, the kinetic parameters of various stages of the processes occurring during the thermal decomposition of waste rubber products are determined. To study the physico-chemical and chemical transformations occurring in waste samples of rubber products with temperature changes, a thermal analysis was carried out. It has been established that the processes of thermal destruction of the carbon component of rubber products are similar to the processes occurring during pyrolysis of solid natural combustible minerals, and conditionally consist of four stages. On the basis of the derivatogram, the temperatures of the endothermic minima were determined, and the temperatures of the processes were determined from the beginning of the peaks of the effects on the DTA curve. To determine the kinetic parameters of various stages of the process of thermal destruction of rubber products without air access, the Arrhenius law was used as the initial equation, which describes the dependence of the reaction rate constant on temperature. It is established that a first-order kinetic equation is acceptable for the process of thermal decomposition of waste rubber products during pyrolysis, activation energies and pre-exponential multipliers of each stage of thermal decomposition are calculated. The lowest reaction rate is observed in the temperature range of 510-780 °C, respectively, this stage is limiting and determines the rate of the process. Based on the results of thermal analysis, a method has been proposed and developed that allows to obtain a refined solid carbon-containing pyrolysis residue by calcining it at a temperature of 800-850 °C in an oxygen-free environment until the complete cessation of gas emission processes. The data obtained are necessary for modeling the pyrolysis process of rubber products on a production scale. Based on laboratory studies and experimental data obtained, it is possible to optimize existing pyrolysis plants for rubber waste. For citation: Makarevich E.A., Papin A.V., Cherkasova T.G. Kinetic characteristics of thermolysis processes of waste rubber products. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2024. V. 67. N 5. P. 107-113. DOI: 10.6060/ivkkt.20246705.6937.