Catalytic Aquathermolysis Of Heavy Oil Research Articles

ZrO2-MoO3/modified lotus stem biochar catalysts for catalytic aquathermolysis of heavy oil at low-temperature

Aquathermolysis is one of the thermochemical reactions in the heavy oil thermal recovery process. The key issue, i.e., the high temperature required by aquathermolysis, can be reduced by the involvement of catalysts. However, the effective working temperature of catalysts is still above 240 ℃, which needs to be further reduced to enhance energy efficiency. Considering that biochar has a high specific surface area, abundant functional groups, a wide temperature window, and can be easily modified, a series of ZrO2-MoO3-based catalysts loaded on raw or three modified lotus stem biochar were studied to investigate heavy oil catalytic viscosity reduction at low temperatures. Physicochemical properties of catalysts were investigated by a variety of characterization methods. The performance of four kinds of catalysts and the influence of reaction conditions (temperature and time) on aquathermolysis were evaluated. The results showed that silane coupling agent KH570 modified biochar (KH570-MLSB) has a higher specific surface area and more functional groups, which help the loading of active components and the dispersion in heavy oil. ZrO2 can form coordination compounds with S atoms in C-S, which greatly weakens the bond energy of C-S and reduces the activation energy of the aquathermolysis. The coordination bonding energy with S of Mo is weaker than that of Zr. The main role of MoO3 is to inhibit the formation of coke. Therefore, catalyst Ⅳ, which consists of KH570-MLSB, ZrO2, and MoO3, has the best catalytic effect at 200 ℃. In addition, the optimum reaction time of the catalyst is 24 h.

Development of a simple and efficient oil-soluble nanocatalytic system for aquathermolysis upgrading of heavy crude oil

Catalytic aquathermolysis is one of the key and cost-effective chemical method for recovering heavy oil. This process transforms the asphaltene and resin compounds of the oil into lighter fractions. Oil-soluble transition metal-based catalysts have been reported as efficient catalysts that improve the viscosity reduction efficiency of the aquathermolysis process. Previous studies have mainly focused on using long alkyl chains as oil-soluble ligands to prepare the catalysts. However, aromatic ligands that effectively interact with asphaltene and resin fractions have not been extensively studied. In other words, the molecular structure of ligand used in the catalyst synthesis significantly changes its activity in aquathermolysis. This study aims to fill this gap using catechol as a novel ligand to develop oil-soluble catalyst (Ni-OSC), which can interact with heavy oil fractions during aquathermolysis. Ni-OSC decreased the content of resin and asphaltene by 32.1% and 26.5%, respectively, and increased the amounts of saturated and aromatic hydrocarbons by 19.6% and 22.9%, respectively, compared to heavy oil. Moreover, a GC–MS study indicated that low molecular weight hydrocarbons in the composition of heavy oil increased, and the relative content of alkanes raised to 79% in the presence of Ni-OSC. The catalyst also increased the concentration of alkylbenzenes and naphthalenes in the composition of aromatic compounds, improving the quality and recovery of heavy oil. Furthermore, the viscosity of heavy oil was considerably reduced, and a maximum hydrogen to carbon ratio of 2.03 was observed in Ni-OSC system. To the best of our knowledge, this is the highest reported hydrogen-to-carbon ratio for catalytic aquathermolysis of heavy oil using oil-soluble catalysts.

Study on catalytic aquathermolysis of heavy oil by simple synthesis of highly dispersed nickel-loaded nitrogen-doped carbon catalysts

Faced with the increasing energy demand, the extraction of heavy oil is crucial. Efficient catalysts can reduce the viscosity and improve the quality of heavy oil. In this paper, the highly dispersed Ni/NC-6.0 catalyst was prepared by one-pot method and was utilized for the viscosity reduction and upgrading of heavy oil. The results of H2-TPD, SEM, TEM, and XPS demonstrate that the average size of Ni/NC-6.0 is about 200 nm, and the Ni atoms coordinated with N atoms are highly dispersed over the surface of carbon support. The experimental results of catalytic aquathermolysis reveal that highly dispersed Ni/NC-6.0 catalyst showed efficient catalytic performance in reducing the degree of asphaltenes branching and cracking the long chains of resin. It can reduce the viscosity by 82.21% and decrease the heavy components by 13.04% through the occurrence of hydrodesulfurization, hydrodenitrogenation, debranching, dealkylation of long-chain, depolymerization, and cracking. This work makes contributions to viscosity reduction and upgrading of heavy oil.

Catalytic upgrading evaluation under steam injection conditions with spectroscopy 1H-NMR

Steam injection has mainly been applied due to its physical recovery mechanisms. However, a chemical process could arise and is called aquathermolysis. These reactions could be favored by the addition of a catalyst, which acts on cracking reactions of some heavy compounds. Therefore, an experimental evaluation of catalytic aquathermolysis of heavy oil was carried out in a microreactor batch. The experiments were performed at three different reaction times (24 h–62 h) and temperatures between 240 °C–300 °C. Iron naphthenate, molybdenum naphthenate, and nickel naphthenate were the catalysts used. Oil upgrading was measured by changes in the physical property, and the identification of reactive molecules by nuclear magnetic resonance 1H-NMR technique to obtain average molecular parameters. The average number of carbons in alkyl chains was determined to simplify the samples’ compositional analysis, as well as the number of substituted rings and the aromaticity factor. The experimental results showed an increase in the viscosity reduction efficiency as Mo < Ni < Fe. In addition, the catalysts increased the API° gravity and decreased the viscosity by 10° and 79%, respectively. Furthermore, naphtha and kerosene production increased the conversion of the 300 °C + fraction up to 8%. Finally, upgraded oils showed a smaller difference in alkyl chains length.

Study on Catalytic Aquathermolysis of Heavy Oil by Simple Synthesis of Highly Dispersed Nickel Loaded Carbon-Doped Nitrogen Catalysts

Study on Catalytic Aquathermolysis of Heavy Oil by Simple Synthesis of Highly Dispersed Nickel Loaded Carbon-Doped Nitrogen Catalysts

Influence of reservoir minerals and ethanol on catalytic aquathermolysis of heavy oil

In this paper, the effect of different types of minerals and alcohols as hydrogen donors on the catalytic aquathermolysis of heavy oil was investigated. The best catalytic effect showed sodium clay. Methanol was demonstrated as the most suitable to enhance viscosity reduction efficiency. Under the optimal conditions of the catalytic aquathermolysis, the viscosity reduction rate can reach 87.32% in comparison with the original oil. Differential scanning calorimetry (DSC), Fourier Transform Infrared Spectrometry (FTIR), Thermogravimetric Analysis (TGA), Elemental analysis, and Gas chromatography-mass spectrometry (GC–MS) were used to study the changes occurring during the catalytic aquathermolysis of crude oil. In addition, several different model compounds (1-octene, thiophene, phenol, pyridine, quinoline, benzothiophene, and nonylphenol) were selected to simulate the chemical changes of crude oil components and to propose the reaction mechanisms.

Synthesis and Characterization of Mechanically Alloyed, Nanostructured Cubic MoW Carbide

Carbides are used extensively as cutting tools, forming dies, and recently in catalysis applications, among other industrial applications. In this work, the synthesis and characterization of a nanostructured MoW bimetallic carbide were carried out by mechanical alloying with a mixture of elemental powders with a nominal composition of W1.5Mo6C2.5 at different grinding times as follows: 25, 50, and 75 h in a low-energy ball mill at a speed of 500 rpm and 125 and 150 h in a high-energy ball mill at a speed of 1500 rpm. The formation of a solid solution was observed at 150 h of milling; the nanostructured bcc MoW carbide corresponded to the main phase in the sample, besides the presence of the nanostructured MoW alloy as a secondary phase with an average crystal size of 40.8 nm. The phases and morphology at every stage of milling were studied by: X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), and Vickers hardness. As the milling time increased, the hardness of these particles increased from 10.5 to 31.48 GPa for the powder particles milled for 150 h. The samples obtained at 125 and 150 h of milling were evaluated during catalytic aqua-thermolysis of heavy oil to analyze fuel desulfurization properties by Fourier transform infrared (FTIR) techniques. The results showed the breaking of S-S bonds, indicating the existence of a desulfurization reaction of heavy oil.

Water-Soluble Complexes Catalyzed Coupling Aquathermolysis of Water-Heavy Oil-Methanol at Low Temperature

A series of complex was synthesized using phenyl hydroxamic acid and metallic chloride, and used for catalytic aquathermolysis of heavy oil at low temperatures for the first time. The effects of water content and catalyst concentration on aquathermolysis were investigated. And then a tri-component coupling aquathermolysis of water-heavy oil-methanol was designed and the reaction conditions were investigated. With the catalyst and methanol, the reaction occurred at temperatures as low as 180°C. The viscosity of the product was also substantially reduced by the decomposition of the large hydrocarbon molecules.

Zn(II) Complex Catalyzed Coupling Aquathermolysis of Water-Heavy Oil-Methanol at Low Temperature

A Zn(II) coordination complex was synthesized, characterized, and used for catalytic aquathermolysis of heavy oil at low temperatures for the first time. The effects of water content and catalyst concentration on aquathermolysis were investigated. And then a tri-component coupling aquathermolysis of waterheavy oil-methanol was designed and the reaction conditions were investigated. With the catalyst and methanol, the reaction occurred at temperatures as low as 180°C. The viscosity of the product was also substantially reduced from around 24 400 to 6420 mPa s by the decomposition of the large hydrocarbon molecules.

Zirconia-Based Nanocatalysts in Heavy Oil Upgrading: A Mini Review

Two main limitations in heavy oil are the recovery and upgrading process, which emphasizes aquathermolysis as an alternative approach to reduce viscosity and increase oil quality simultaneously. In addition to facilitating solubilization of asphaltene, hot water (subcritical and supercritical) injected into the heavy oil reservoir also serves as a hydrogen donor. The main purpose of this article is to review catalytic aquathermolysis of heavy oil over zirconia, which is a robust oxide. Zirconia-based nanocatalysts are promising due to their high oxygen storage capacity, acidity, and stability in sub- and supercritical water. The article also elaborates on various methods to fabricate nanosized zirconia with different shapes and sizes by sol–gel, spray pyrolysis, electrospinning, and hydrothermal techniques.

Mechanism of Underground Heavy Oil Catalytic Aquathermolysis

Field tests carried out in Shengli oi lfield showed that underground catalytic aquathermolysis can reduce heavy oil viscosity by about 70-80% with a long-term effect, contributing greatly to oil production increase. Experimental results proved that average molecular weight and contents of heavy components and heteroatoms of heavy oil decrease after the treatment and that H/C ratio and the content of light fractions increase due to reactions, such as hydrogenation, ring opening, desulfurization, etc. initiated by the catalyst, high-temperature water, and reservoir minerals. The study results suggest that in-situ catalytic aquathermolysis of heavy oil is technically feasible.

Catalytic aquathermolysis of heavy oil by coordination complex at relatively low temperature

A series of Mannich base-transition metal coordination complex was synthesized and used for the catalytic aquathermolysis of heavy oil, among which we found that the Ni(II) complex is the most effective one. After reacted under a relative low temperature, 180°C, for 24 h, the viscosity of the heavy oil was decreased by 75.2% using 0.5 wt % Ni(II) complex. The results showed that the content of resin and asphaltenes was decreased, while the content of saturate and aromatic were increased after aquathermolysis reaction. Besides, the catalytic aquathermolysis could both decrease the viscosity of heavy oil, and reduce the content of heteroatoms, resulting in flow properties enhanced and the quality upgraded.

The use of a tartaric–Co(II) complex in the catalytic aquathermolysis of heavy oil

ABSTRACTA tartaric–Co(II) complex was synthesized and then used in aquathermolysis of heavy oil as a catalyst at relatively low temperature, 180°C. The effects of water amount and catalyst concentration on aquathermolysis were investigated in this work. The crude oil before and after aquathermolysis was fully characterized, and the mechanism of viscosity reduction was discussed at last. The results show that heavy oil can undergo aquathermolysis in the present of water and the tartaric–Co(II) complex at low temperature. Besides, the catalytic aquathermolysis could not only decrease the viscosity of heavy oil, but also remove some heteroatoms, finally making the flow properties better and the quality upgraded.

Clean aquathermolysis of heavy oil catalyzed by Fe(III) complex at relatively low temperature

ABSTRACTIn order to develop a clean catalyst for aquathermolysis of heavy oil at relatively low temperature, a series of water-soluble Fe(III) complexes were prepared as the catalysts for the catalytic aquathermolysis of heavy oil. Under the optimized condition, the adding amount of Fe-3 (a complex of Fe(III) and citrate) is 0.1%, the reaction temperature is 180°C, and the reaction time is 24 h, the heavy oil viscosity reduction ratio reaches to 80.1% (40°C). Results of the composition analysis show that the contents of resin and asphaltene decrease and the saturated hydrocarbon and aromatic increase. GC analysis shows that the light components increase remarkably after the aquathermolysis.

Viscosity reduction of citric-Fe(III) in catalytic aquathermolysis of heavy oil at low temperature

A Fe(III) coordination complex was synthesized, characterized, and then used in aquathermolysis of heavy oil as catalyst at relatively low temperature, 180°C. The effects of water amount, catalyst concentration on aquat hermolysis were investigated in this work. The crude oil before and after aquathermolysis was fully characterized, and the mechanism of viscosity reduction was discussed in detail. The results show that heavy oil can undergo aquathermolysis in the present of water and citric-F e(III) complex at low temperature. Besides, the catalytic aquathermolysis could not only decrease the viscosity of heavy oil, but also remove some heteroatoms, finally make the flow properties better and the quality upgraded.

Methanol enhanced catalytic viscosity-reduction of heavy oil by transition metal-Mannich base complex under low temperature

A series of transition metal-Mannich base complex was synthesized and screened for catalytic aquathermolysis of heavy oil and the results showed that the Ni(II)-Mannich base complex is the most effective one. The structure of catalyst was characterized by Fourier transform infrared (FTIR), ultraviolet and visible spectrophotometer (UV), and the group compositions C/H/N elemental analysis (EL), and thermogravimetric analysis (TGA) of the heavy oil were also conducted. The viscosity of the heavy oil can be decreased by 82.6% using 1.0 wt % catalyst with 15 wt % methanol in a reaction under 180°С for 24 h, and the composition analysis shows that 9.0% asphaltene is converted to resin and saturated HC. The group composition and the element content of the heavy oil before and after the aquathermolysis reaction were tested and analyzed.

Catalytic aquathermolysis of Shengli heavy crude oil with an amphiphilic cobalt catalyst

An interfacially active cobalt complex, cobalt dodecylbenzenesulfonate, was synthesized. Elemental analysis, atomic absorption spectroscopy, Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis, and surface/interfacial tension determination were performed to investigate the properties of the catalyst. Results showed that the synthesized catalyst showed active interfacial behavior, decreasing the surface tension and interfacial tension between heavy oil and liquid phase to below 30 and 1.5 mN/m, respectively. The catalyst was not thermally degraded at a temperature of 400 °C, indicating its high thermal stability. Catalytic performance of the catalyst was evaluated by carrying out aquathermolysis. The viscosity determination showed that the viscosity of the heavy oil decreased by 38 %. The average molecular weight, group compositions, and average molecular structure of various samples were analyzed using elemental analysis, FT-IR, electrospray ionization Fourier transform ion cyclotron resonance (ESI FT-ICR MS), and 1H nuclear magnetic resonance. Results indicated that the catalyst could attack the sulfur- and O2-type heteroatomic compounds in asphaltene and resin, especially the compounds with aromatic structure, leading to a decrease in the molecular weight and then the reduction in the viscosity of heavy oil. Therefore, the synthesized catalyst might find an application in catalytic aquathermolysis of heavy oil, especially for the high-aromaticity heavy oil with high oxygen content.

Catalytic Aquathermolysis of Heavy Oil With Oil-soluble Multicomponent Acrylic Copolymers Combined With Cu2+

A kind of oil-soluble multicomponent acrylic copolymer combined with Cu2+ was synthesized and used for catalytic aquathermolysis of heavy oil. This work showed this copper-bearing copolymer led to 84.52% viscosity reduction for the Lukeqin heavy oil at 513.15 K, and converted 10.01% of the resin fraction and 2.85% of the asphaltene fraction into light oil content. After aquathermolysis with this catalyst, some parts of the long-chain saturated hydrocarbons were broken into short-chain ones, and the aromaticity and aromaticity condensation of the resin and asphaltene decreased.

Synthesis of Fe&lt;sub&gt;3&lt;/sub&gt;O&lt;sub&gt;4 &lt;/sub&gt;Nanoparticles Using the Co-Precipitation Method and its Development into Nanofluids as a Catalyst in Aquathermolysis Reactions

Catalytic aquathermolysis is proposed as one of the potential methods which functions to reduce the viscosity of heavy oil for ease of extraction. In this research, we have developed a solution dispersed catalyst of Fe3O4 nanoparticles through a co-precipitation method. FeCl3·6H2O and FeCl2·4H2O were used to serve as an Fe source, with NaOH as a co-precipitator. The as-synthesized nanoparticles were characterized by X-ray diffraction (XRD) to verify materials. In order to be able to be used in the reservoir, the prepared powder was further dispersed into a base fluid with the addition of a dispersant by an ultrasonication for 2 hours. The stable nanofluid was achieved using the ratio of ethylene glycol/water mixture of 20%:80%. Dynamic light scattering (DLS) characterization results showed that the average size of the particle was about 309 nm, which is small enough to ensure its ability to pass through rock pores. Catalytic aquathermolysis of heavy oil in laboratory scale was employed under the addition of stable nanofluid at 200°C for 6 hours. The viscosity of heavy oil after the reaction could be reduced up to 71.3%.

Study of catalytic aquathermolysis of heavy oil in the presence of a hydrogen donor

We have studied the effect of catalytic aquathermolysis of heavy oil in the presence of a hydrogen donor (formic acid) on the viscosity of Liaohe extra-heavy oil. The paraffinic/naphthenic and aromatic hydrocarbon content of the oil as well as the H:C ratio of the oil increase after aquathermolysis in the presence of a hydrogen donor, while the sulfur, resin, and asphaltene content decreases dramatically. We use the thermogravimetric method to show that with aquathermolysis in the presence of formic acid, a substantial portion of the asphaltenes in the heavy oil is converted to paraffins. Accelerating the aquathermolysis reaction results in a synergistic effect between the catalyst and the hydrogen donor.