Oxidation of Heavy Oil Using Oil-Dispersed Transition Metal Acetylacetonate Catalysts for Enhanced Oil Recovery

Abstract

In this work, several transition metal-based acetylacetonates (Ni, Cu, and Fe) were prepared as oil-dispersed catalysts for heavy oil oxidation. X-ray diffraction (XRD), scanning electron microscopy (SEM), and Mössbauer spectroscopy were used for the characterization of catalysts. The effectivity of catalysts in the oxidation of heavy oil was investigated by a thermogravimetry method coupled with infrared spectroscopy (TG-FTIR) at four different heating rates (4, 6, 8, and 10 °C/min) and self-designed porous medium thermo-effect cell (PMTEC) techniques. The activation energy calculations using three isoconversional methods, Ozawa–Flynn–Wall (OFW), Kissinger–Akahira–Sunose (KAS), and Friedman, were performed based on thermal analysis data. The results showed that the bidentate ligand acetylacetonate (acac) provided good enough distribution of catalysts in heavy oil because in the presence of Cu­(acac)2, Fe­(acac)3, and Ni­(acac)2, the oxidation temperature decreased in both fuel deposition (FD) and high-temperature oxidation (HTO). The activation energy of FD and HTO districts showed that Cu­(acac)2 more efficiently catalyzed the oxidation of heavy oil than Fe­(acac)3 and Ni­(acac)2. The usage of Cu­(acac)2 helped decrease the average activation energy of the in situ combustion process from 177 to 117 kJ/mol, from 187 to 127 kJ/mol, and from 198 to 128 kJ/mol based on OFW, KAS, and Friedman methods, respectively. The in situ transformation of the catalysts in the presence of heavy oil was studied under different isothermal conditions. Based on XRD and SEM data at 400 °C, Cu­(acac)2 and Ni­(acac)2 were transformed to CuO and NiO nanoparticles as the active form of catalysts. For Fe­(acac)3, it was found that at 400 °C, it transformed to magnetite (Fe3O4) species; however, at 500 °C, hematite (α-Fe2O3) and maghemite (γ-Fe2O3) were the most predominant species. The heavy oil oxidation using these low-cost and easy to prepare catalysts could be the best route for improving the efficiency of in situ combustion in field applications.

Effect of Different Water Content and Catalyst on the Performance of Heavy Oil Oxidation in Porous Media for In Situ Upgrading

“…The SARA analysis and viscosity of oil were conducted in accordance with ASTM D 4124 and ASTM D 445, respectively. 49 The initial and upgraded oils were evaluated for elemental composition (C, H, N, and S) using a PerkinElmer 2400 Series II analyzer according to ASTM (P/N 0240-1289). 9 2.2.…”

“…The used heavy crude oil was provided from the Tatarstan oil field (Russia), and its physical and chemical properties are listed in Table The silica gel particles (ACROS 24037) were purchased from TatchemProduct Co. (Russia). The SARA analysis and viscosity of oil were conducted in accordance with ASTM D 4124 and ASTM D 445, respectively . The initial and upgraded oils were evaluated for elemental composition (C, H, N, and S) using a PerkinElmer 2400 Series II analyzer according to ASTM (P/N 0240-1289) …”

“…48 Using metal catalysts with a high valence electronic state and being oil-soluble or oil-dispersed in heavy crude oil in the ISC process dramatically improves stability of the combustion front. 8,21,48,49 Recently, oil-soluble and oildispersed catalysts, due to their high distribution in the crude oil environments, have been considered as an option for oil oxidation in porous media to improve the enhanced oil recovery and reduced the viscosity of the produced oil. 8,21,50−54 Viscosity reduction of heavy oil during recovery is the key aspect for the success of the recovery method.…”

“…Because of these unpleasant aspects of metals, metal oxides, and water-soluble metal salts as a catalyst or a precursor, ISC technology has tended to emphasize the need for other species of catalysts or precursors that are widely distributed and readily soluble in heavy oil continue . Using metal catalysts with a high valence electronic state and being oil-soluble or oil-dispersed in heavy crude oil in the ISC process dramatically improves stability of the combustion front. ,,, Recently, oil-soluble and oil-dispersed catalysts, due to their high distribution in the crude oil environments, have been considered as an option for oil oxidation in porous media to improve the enhanced oil recovery and reduced the viscosity of the produced oil. ,,− Previous work by our group has shown that oil-dispersed iron oxide is highly distributed in heavy oil environments, including both liquid and porous forms, resulting in lower ignition temperatures and oxidation temperatures in both stages of heavy oil combustion (LTO and HTO) …”

Crude Oil Oxidation in an Air Injection Based Enhanced Oil Recovery Process: Chemical Reaction Mechanism and Catalysis

“…Khelkhal et al − also investigated the impact of bimetallic Mn@ Cu tallates, iron tallates, and copper tallates on crude oil combustion. Babapour Golafshani et al synthesized copper, nickel, and iron acetylacetonates and studied their catalytic effects as well as in situ transformation. The results indicated that acetylacetonate made an even dispersion of catalysts in an oil environment, and the catalysts reduced the reaction temperature of FD and HTO.…”