Aquathermolysis of heavy oil in the presence of bimetallic catalyst that form in-situ from the mixture of oil-soluble iron and cobalt precursors

Abstract

The design of highly efficient catalysts of cracking reactions for intensification of thermal enhanced oil recovery technologies is a relevant task. Moreover, the cost-effective industrial synthesis of such catalysts is very important. In this paper, we discuss the efficiency of bimetallic catalyst, which forms in-situ from the mixture of oil-soluble iron and cobalt precursors, on the processes of upgrading heavy oil in the reservoir of Tatarstan Republic (Russia). A simulation of aquathermolysis was carried out in a high-pressure reactor – autoclave at 150-250оС. The treatment time varied from 6 to 24 hours and the share of catalyst and hydrogen donor was 2 %wt. each. The phase composition of the active form of binary catalyst was estimated from the result of X-ray diffraction measurement. It is characterized by the presence of individual (Fe3O4 and Fe2O3) and mixed oxides with ideal stoichiometry – СоFe2O4. The formation of cobalt sulfide (CoS2) was observed, which indicates the destruction of C-S bonds in high-molecular components of oil. According to the results of SARA-analysis and rheology behavior, the catalyst intensifies destructive processes of resinous compounds (their content reduces more than 45%). This provides an increase in the content of saturated hydrocarbons by 16% and redistribution of aromatic fragments in hydrocarbons with hybrid structure. Thus, the reduction of dynamic viscosity by 32% was succeeded.

Catalytic Aquathermolysis of Boca de Jaruco Heavy Oil with Nickel-Based Oil-Soluble Catalyst

“…Many studies have been published on the application of catalysts during steam treatment of heavy hydrocarbons. Research results show that catalysts stimulate hydrogenation, hydrogenolysis, hydrolysis, and cracking reactions, which result in the enhancement of the physical and chemical, as well as rheological, properties of crude oil [7][8][9]. The authors imply that in the presence of catalysts the content of saturates and aromatics were increased, while the content of solid n-alkanes, resins, and asphaltenes were reduced.…”

Experimental Considerations for Proper Development of Aquathermolysis Tests in Batch Reactor Systems

“…Figure 2 shows the reaction mechanism of hydrogen formation from tetralin and decalin. 34,38 As a result, the concentration of free radicals in the reaction system decreases, inhibiting coke formation. However, there are still some limitations of these solvents during their application in field tests due to effects of toxicity, corrosion, combustion, volatility, and considerable cost.…”

“…To provide a higher hydrogen amount in the reaction system and saturate the generated free radicals, some solvents with hydrogen donation capacity, such as organic acids or functionalized cyclic hydrocarbons, have been deeply studied to bring about enhancement of viscosity reduction. These hydrogen donors, among which are tetralin, − decalin, glycerol, , cyclohexane, and some alcohols, , work better when incorporated with catalysts, controlling the increase in the molecular weight of heavy compounds and the viscosity regression. Liu and Fan studied the effect of tetralin as a hydrogen donor on the viscosity of Liaohe heavy crude oil at 240 °C and a period of 24 h with 20 wt % water in the steam stimulation process.…”

Catalytic Hydrothermal Conversion of Heavy Oil in the Porous Media

“…This creates certain problems for further transportation and refinery of heavy crude oil. , The complex geological and geochemical burial conditions in Permian deposits make thermal heavy oil recovery more complicated, because it is related to significant technical and environmental problems. − One has to note that the most explored heavy oil and natural bitumen reservoirs in sandstone rocks of Sheshminsky horizon of Permian deposits are located among localities at shallow depths, on the border of fresh and saline waters. In this regard, one of the most promising directions is a research dedicated to the transformation of heavy oil and natural bitumen into light hydrocarbons under reservoir conditions, aiming to reduce their viscosity. ,,, In the literature, modeling the thermal and catalytic conversion of crude oil and organic matter (OM) under the influence of steam is considered as one of the methods for studying the hydrocarbon generation processes and their subsequent transformation in sediments. − Recently, there are many works devoted to the application of oil-soluble catalysts containing variable valence metals to improve the efficiency of heavy oil production. In refs, − ,,− the activity of nickel, copper, iron, and manganese naphthenates during the upgrading of heavy oil sample from Luccin (China) at a temperature of 365 °C with a duration of 40 min was investigated, which were formed from oil-soluble precursors.…”

“…Recently, there were many research works, wherein authors propose the use of compositions with various metals. In ref, the catalytic aquathermolysis at 180 °C using an oil-soluble cobalt precursor reduced the amount of resins, while the iron-based catalyst at 200 °C intensified the destruction of C–C bonds, mainly in asphaltene molecules. In ref, a new catalyst based on Ni–Co–Mo was employed for the aquathermolysis of heavy oil from the Oman field at 280 and 300 °C.…”