Effect of process conditions on the composition of products in the conventional and deep catalytic cracking of oil fractions

Abstract

With the purpose of increasing the yield of light C 2 −C 4 olefins in comparison with that in conven tional catalytic cracking, we experimentally study the effect of temperature and catalyst to oil ratio on the dis tribution of the basic products of oil catalytic cracking on the bizeolite and industrial LUX catalysts. The bizeolite catalyst contains ZSM 5 and ultrastable Y zeolites in equivalent amounts, while the LUX catalyst contains 18 wt % of Y zeolite in the HRE form. As shown by the results of our tests, the yield of C 2 -C 4 olefins and gasoline in the deep catalytic cracking of hydrotreated vacuum gasoil on the bizeolite catalyst within a range of catalyst to oil ratios of 5-7 and temperatures of 540-560°C reaches 32-36 and nearly 30 wt %, respectively. In cracking on the LUX catalyst under similar conditions, the yield of light olefins and gasoline is 12-16 and 37-45 wt %, respectively. The distribution of target products in the deep catalytic cracking of different hydrocarbon fractions (vacuum gasoil, gas condensate, its fraction distilled from the cut boiling below 216°C, and the hydrocracking heavy residue) on the bizeolite catalyst is studied. It is shown that the fractions of gas condensate and hydroc racking residue can serve as an additional source of hydrocarbon raw materials in the production of olefins.

Two-Step Thermal Cracking of an Extra-Heavy Fuel Oil: Experimental Evaluation, Characterization, and Kinetics

“…Notably, the maximum yield of 74.7 wt % olefins based on the HCO feedstock (55.1 wt % based on the initial HFO) was obtained from thermal cracking of HCO at 800 °C. This is an outstanding amount when compared to the values reported in the literature even with lighter feedstocks or even in the catalytic cracking routes. ,,− At the same time, however, the methane-to-olefins (M/O) selectivity factor was maximized at 800 °C, indicating that the cracking severity was also maximized at this temperature. The remarkably high olefin yields obtained here indicated that although the feedstock at hand was an extra-heavy hydrocarbon fraction, it contained amenable components and structures in its composition that could be cracked to astonishing yields of light olefins at temperatures common in industrial olefin plants using a proper two-step process.…”

Mathematical modelling of catalytic cracking riser reactor

“…The operating efficiency of catalytic cracking units is determined by a broad range of operation indicators of non-stationary conjugate "riser-regenerator" system [1][2][3][4]. The quality and the yield of the light fractions in the catalytic cracking depend on the feedstock composition, the process conditions of the reactor and regenerator unit, the type and activity of the catalyst circulated continuously between the reactor and regenerator, etc.…”

Propylene production technology: Today and tomorrow

“…In Among the Russian developers of cracking pro cesses and catalysts, OOO Avtotekhproekt is worth noting, whose experts proposed an original version of two stage cracking of vacuum gasoil using a bizeolite catalyst [42,43]. The Institute of Hydrocarbons Pro cessing, Siberian Branch, Russian Academy of Sci ences, patented a catalyst for deep cracking of heavy oil fractions, which can provide an overall yield of C 2 -C 4 alkenes of up to 36-42 wt %, including 15.0-19.7 wt % propylene [44,45]. The catalyst contains the ultrast able zeolite Y (10-30 wt %) and zeolite HZSM 5 (10-30 wt %).…”