Activation of carbon sorbents used in the hydrocracking process of vacuum oil distillation residue

Zaitseva E. G, Institute of Petroleum, Chemistry and Nanotechnologies, Kazan National Research Technological University, Kazan, 420015 Tatarstan, Russia
Safiulina A. G, Institute of Petroleum, Chemistry and Nanotechnologies, Kazan National Research Technological University, Kazan, 420015 Tatarstan, RussiaFollow
Petrov S. M, Institute of Petroleum, Chemistry and Nanotechnologies, Kazan National Research Technological University, Kazan, 420015 Tatarstan, Russia

Article Type

Research Paper

Abstract

The article is devoted to the study of the effect of modification of carbon sorbents, used as a catalyst during hydrocracking of vacuum residue, on their textural characteristics. Methods for modifying the main textural characteristics of the carbon support are shown. They provide a high degree of conversion of residual asphaltene associates during hydrocracking. To determine the optimal pore space in carbon sorbents, the sizes of asphaltene associates in the initial feedstock were determined by laser diffraction. For the first time, a comparative analysis of the sizes of asphaltene associates with the pore space of a carbon sorbent was carried out. Using X-ray diffraction, infrared spectroscopy, X-ray fluorescence and thermogravimetric analysis, the distinctive features of the thermal activation of carbon sorbents were established. Based on X-ray diffraction, a crystalline phase of calcite was discovered in the composition of carbon sorbents. As a result of thermal activation, according to the X-ray fluorescence method, the sulfur content in carbon sorbents decreases. It has been shown that activation of carbon with water vapor increases the formation of mesapores and macropores, but no direct dependence of the specific surface area on the thermal activation medium was found. It has been shown that within industrially used carbon sorbents, the conversion of asphaltenes does not occur on the internal surface of the pores, but on their much smaller outer surface. An increase in the contact area of asphaltene associates with the surface of carbon sorbents (due to an increase in pore diameters) can be achieved by their heat treatment at a temperature of 400 °C in a nitrogen atmosphere or steam-thermal treatment at a temperature of 800 °C. Additional use of the internal surface inside the pores of carbon sorbents during asphaltene cracking leads to an increase in their conversion degree. The textural characteristics of coals can serve as indicators of their applicability as additives in the reaction media for vacuum residue hydrocracking.

Keywords

Vacuum residues; carbon sorbents; hydrocracking; carbon carrier; specific surface area; pore size and pore volume

Recommended Citation

G, Zaitseva E.; G, Safiulina A.; and M, Petrov S. (2024) "Activation of carbon sorbents used in the hydrocracking process of vacuum oil distillation residue," Egyptian Journal of Petroleum: Vol. 33 : Iss. 2 , Article 13.
Available at: https://doi.org/10.62593/2090-2468.1029