Intensified Viscosity Reduction of Heavy Oil by Using Reservoir Minerals and Chemical Agents in Aquathermolysis

Through laboratory experiments with samples from Daqing and Liaohe oilfields, the effects of reservoir mineral,NiSO4 and tetrahydronaphthalene (THN) were investigated in the aquathermolysis (AT) of heavy oi1. The results indicate that, in contrast with simple AT, the addition of reservoir minerals leads to lower average molecular weight, higher contents of saturated and aromatic hydrocarbon and lower contents of resin and asphalting, and the viscosity reduction ratio of the two oi1 samples increases from 7.41% and 12.95% to 16.05% and 25.29% respectively, which means that reservoir minerals can catalyze the AT of heavy oi1.With the addition of NiSO4 and THN into the reaction system, the average molecular weight of the reaction products decreases further, the contents of saturated and aromatic hydrocarbon increase and the contents of resin and asphalting decrease further, the viscosity decreases greatly with a reduction ratio as high as 84.39%.

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Fabrication of Magnetic Catalyst Fe3O4-SiO2-V3 and Its Application on Lignin Extraction from Corncob in Deep Eutectic Solvent

Polymers ◽

10.3390/polym13101545 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1545

Author(s):

Maonan Yuan ◽

Zhen Wang ◽

Yu Liu ◽

Guihua Yang

Keyword(s):

Molecular Weight ◽

Choline Chloride ◽

Average Molecular Weight ◽

Deep Eutectic Solvent ◽

Reaction System ◽

2D Nmr ◽

Number Average Molecular Weight ◽

Batch Experiments ◽

Weight Average Molecular Weight ◽

Lignin Extraction

Fe3O4-SiO2-V3 was prepared by deposited H6PMo9V3O40 on Fe3O4-SiO2 and employed as a catalyst to extract lignin from corncob in deep eutectic solvent (choline chloride/lactic acid = 1/10). Batch experiments were conducted in an autoclave under the conditions of 500 kPa, 90–130 °C and 15 h, while the dosage of the catalyst was set as a variable. Results indicated that the catalyst could effectively improve the qualities of the lignin, while the characteristics of the lignin showed prominent changes with the participation of the catalyst: the extraction rate increased from 71.65% to 98.13%, the purity was improved from 85.62% to 97.09%, and both the number average molecular weight and the weight average molecular weight also decreased significantly. Besides, the molecular distribution of the lignin achieved from the CC-LA-Fe-Si-V3 reaction system was found to be more highly concentrated (Polydispersity index = 1.746). Results from 2D NMR HSQC analysis indicated that lignin fractions achieved from the CC-LA-Fe-Si-V3 system showed distinct destruction involving C2-H2 in guaiacyl units (G), C5-H5 in guaiacyl units (G), and the Cγ-Hγ in γ-hydroxylated β-O-4′ substructures, but little changes in the Cγ-Hγ in phenylcoumaran substructures.

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A Preliminary Investigation Into the Characterization of Asphaltenes Extracted From an Oil Sand and Two Vacuum Residues From Petroleum Refining Using Nuclear Magnetic Resonance, DEPT, and MALDI-TOF

Journal of Energy Resources Technology ◽

10.1115/1.4035746 ◽

2017 ◽

Vol 139 (3) ◽

Cited By ~ 9

Author(s):

Ce Zheng ◽

Mingming Zhu ◽

Wenxu Zhou ◽

Dongke Zhang

Keyword(s):

Molecular Weight ◽

Nuclear Magnetic Resonance ◽

Magnetic Resonance ◽

Polycyclic Aromatic Hydrocarbon ◽

Aromatic Hydrocarbon ◽

Average Molecular Weight ◽

Molecular Structures ◽

Oil Sand ◽

Maldi Tof ◽

Polycyclic Aromatic

This paper reports the findings of an investigation into the molecular structures and properties of three asphaltene samples, namely, an asphaltene sample extracted from Buton Oil Sand (Indonesia), and two asphaltene samples extracted from vacuum residues from Liaohe Refinery (China) and Vene Refinery (Venezuela), respectively. The average molecular structural parameters, including the average polycyclic aromatic hydrocarbon (PAH) size, average side chain length, and average molecular weight (AMW), of the three asphaltene samples were estimated using data from nuclear magnetic resonance (NMR) in combination with distortionless enhancement by polarization transfer (DEPT), and then compared against each other. The molecular weight distributions (MWDs) of the three asphaltene samples were measured using a matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. The results indicated that the island molecular architecture predominated in all three asphaltenes and the average polycyclic aromatic hydrocarbon size was found to be six rings. The average molecular weight of the Buton asphaltene sample was found to be ca. 800 Da while those of the two petroleum asphaltene samples were approximately 600 Da. In comparison, the Buton asphaltene sample contained a much higher level of oxygen and sulfur, but a lower aromaticity than those of the two petroleum asphaltene samples. The use of liquid NMR in combination with DEPT was shown to provide an effective method for characterization and estimation of the molecular structures of asphaltenes, supported by MALDI-TOF mass spectra.

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Synthesis and Molecular Dynamics Simulation of Amphiphilic Low Molecular Weight Polymer Viscosity Reducer for Heavy Oil Cold Recovery

Energies ◽

10.3390/en14216856 ◽

2021 ◽

Vol 14 (21) ◽

pp. 6856

Author(s):

Chao Ma ◽

Xingyu Liu ◽

Longlong Xie ◽

Yan Chen ◽

Wendong Ren ◽

...

Keyword(s):

Molecular Dynamics ◽

Molecular Weight ◽

Molecular Dynamics Simulation ◽

Potential Energy ◽

Network Structure ◽

Heavy Oil ◽

Dynamics Simulation ◽

Viscosity Reduction ◽

Low Molecular Weight ◽

Viscosity Reducer

In order to reduce the viscosity of heavy oil, the performance of emulsifying viscosity reducers is limited. In this study, a new kind of amphiphilic low molecular weight viscosity reducer was prepared by emulsion copolymerization of acrylamide (AM), acrylic acid (AA), 2-acrylamido-2-methylpropanesulfonic acid (AMPS), and Butene benzene (PB). The synthesis feasibility and viscosity reduction mechanism of viscosity reducer in heavy oil were explored using Materials Studio software from the perspective of molecular dynamics. The results of the molecular dynamics simulation revealed that the addition of viscosity reducer into heavy oil varied the potential energy, non-potential energy, density and hydrogen bond distribution of heavy oil. Benefiting from its structure, the benzene ring in PB was well embedded in the interlayer structure of asphaltene, contributing to weaken the network structure of the heavy oil. Moreover, the two strong polar groups (COO− and SO3−) of AA and AMPS, which constituted the branched chains of the viscosity reducer’s molecular structure, gradually disassembled the network structure from the ‘inward’ to the ‘outward’ of the heavy oil network structure, thereby driving heavy oil viscosity reduction (as clarified by molecular dynamics). Owing to its temperature resistance, this kind of new amphiphilic low molecular copolymer could be an effective viscosity reducer for heavy oil cold recovery at elevated temperatures.

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Enhanced Swelling Effect and Viscosity Reduction of Solvent(s)/CO2/Heavy-Oil Systems

SPE Journal ◽

10.2118/150168-pa ◽

2013 ◽

Vol 18 (04) ◽

pp. 695-707 ◽

Cited By ~ 88

Author(s):

Huazhou Li ◽

Sixu Zheng ◽

Daoyong Yang

Keyword(s):

Molecular Weight ◽

Oil Recovery ◽

Heavy Oil ◽

Good Accuracy ◽

Saturation Pressure ◽

Viscosity Reduction ◽

Binary Interaction ◽

Binary Interaction Parameter ◽

Reduction Of Co2 ◽

Swelling Factor

Summary In this paper, techniques have been developed to examine the enhanced swelling effect and viscosity reduction of CO2-saturated heavy oil with the addition of either solvent C3H8 or solvent n-C4H10. Experimentally, pressure/volume/temperature (PVT) tests are conducted to measure the saturation pressure, swelling factor, and viscosity of the C3H8/heavy-oil system, the C3H8/CO2/heavy-oil system, and the n-C4H10/CO2/heavy-oil system, respectively, in the overall temperature range of 280.45 to 391.55 K. It has been found that an increased swelling effect of heavy oil is obtained by adding the gas solvent C3H8 or n-C4H10 into the CO2 stream. An enhanced viscosity reduction of the CO2/heavy-oil system is also achieved in the presence of either C3H8 or n-C4H10. The enhanced swelling effect and viscosity reduction caused by adding either C3H8 or n-C4H10 into the CO2 stream are particularly favorable for achieving a higher heavy-oil recovery compared with pure-CO2 processes. Theoretically, three binary-interaction-parameter (BIP) correlations in the Peng-Robinson (PR) equation of state (EOS) (PR-EOS) method have been proposed for respectively characterizing CO2/heavy-oil binaries, C3H8/heavy-oil binaries, and n-C4H10/heavy-oil binaries by treating each oil sample as a single pseudocomponent with its molecular weight (MW) and specific gravity (SG). The BIP correlations (together with the PR-EOS) can be used to predict the saturation pressures and swelling factors of the C3H8/CO2/heavy-oil system and the n-C4H10/CO2/heavy-oil system with a generally good accuracy.

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The Structure of Radiation Cross-Linked Poly (ethylene oxide) Gels

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100064438 ◽

1971 ◽

Vol 29 ◽

pp. 76-77

Author(s):

C. E. Cluthe ◽

G. G. Cocks

Keyword(s):

Molecular Weight ◽

Ethylene Oxide ◽

Parallel Plate ◽

Average Molecular Weight ◽

Radical Reaction ◽

Free Radical Reaction ◽

Nitrogen Gas ◽

Poly Ethylene Oxide ◽

Poly Ethylene ◽

Initial Viscosity

Aqueous solutions of a 1 weight-per cent poly (ethylene oxide) (PEO) were degassed under vacuum, transferred to a parallel plate viscometer under a nitrogen gas blanket, and exposed to Co60 gamma radiation. The Co60 source was rated at 4000 curies, and the dose ratewas 3.8x105 rads/hr. The poly (ethylene oxide) employed in the irradiations had an initial viscosity average molecular weight of 2.1 x 106.The solutions were gelled by a free radical reaction with dosages ranging from 5x104 rads to 4.8x106 rads.

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