Petroleum cokes are the products of deep thermal processing of heavy oil residues – asphaltenes, resins, fuel oil, tar, etc. The high carbon content in petroleum cokes composition and the ability to thermal modification make them a promising raw material to product activated carbons. This paper presents the results of studies of petroleum coke obtained by the method of delayed coking, with an increased yield of volatile substances as raw materials to use in activated carbon technology. Based on the results of thermogravimetric analysis and analysis of technological parameters of obtaining petroleum coke, the modes of thermal modification of samples in the process of obtaining activated carbon were selected. The pyrolytic gas chromatography method was used to identify the products of thermal decomposition of petroleum coke samples at different stages of activated carbon production technology. It is shown that the main gaseous products of pyrolysis are polycyclic aromatic hydrocarbons that release in the temperature range from 200 to 600 °C. During pyrolysis of carbonized coke samples, gaseous products do not release, and during pyrolysis of activated coke, the release of furan compounds and benzene is observed. Samples of petroleum coke modified with a solution of nitric acid, during pyrolytic analysis, show a complete absence of volatile pyrolysis products. Based on samples of petroleum coke that have been pretreated by various methods, series of activated carbon samples were obtained and their porous structure was studied. The use of a nitric acid solution for pretreatment of a sample of petroleum coke led to an increase in specific surface area and volume of sorption pores over 30-47%. For citation: Farberova E.A., Pershin E.A., Maksimov A.S., Khodyashev N.B., Smirnov S.A., Kuz’minykh K.G. Research of the petroleum coke thermal properties in activated carbon production process. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2023. V. 66. N 6. P. 102-110. DOI: 10.6060/ivkkt.20236606.6776.