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Thiophene sulfide is difficult to be removed by hydrodesulfurization. In this study, ZnCl2-waste paper fiber activated carbon was used as adsorbent to remove thiophene sulfide from simulated oil by hydrothermal modification. Under the optimum condition of ammonia modification, the adsorption capacity of modified adsorbent to BT is 14.8 mg S/g, 2.98 times that of unmodified. BET, FTIR and Boehm analysis showed that the mesopore volume of ammonia modified adsorbent increased by 96.62% and the mesopore ratio increased from 12.58% to 43.40%, which was conducive to improving the adsorption rate. After modification, the basic groups on the surface of the adsorbent increased by 44.3 times, and –NH3+, –OH and –NH2 enhanced the electron attraction and hydrogen bonding force between the adsorbent and BT molecule. Adsorption isotherms, adsorption kinetics and adsorption thermodynamics show that the adsorption process is spontaneous, entropic and exothermic. The pseudo-second-order kinetic rate constant increases with the increase of adsorption temperature, indicating that the increase of temperature is beneficial to accelerate the adsorption rate. The adsorption desulfurization process follows the mechanism of single and multilayer adsorption mixing. The results of this study can help to reveal more clearly that biobased activated carbon can be modified to adsorb thiophene sulfide. Ammonia modified adsorbents enhance the adsorption capacity for benzothiophene [ABSTRACT FROM AUTHOR]

Nickel nanoparticles was supported on sawdust carbon via a hydrothermal method followed by calcination and used as a catalyst for heavy crude oil upgrading experiment. The performance of catalyst on catalytic pyrolysis of heavy crude oil was studied by laboratory experiments. The experimental results showed that under the reaction conditions of 350 °C, 30 min and 0.1 wt% catalyst, the viscosity reduction ratio of heavy crude oil was 74.50%, the viscosity can be reduced from 16,000 mPa·s (50 °C) to 4080 mPa·s, and the net efficiency of catalyst was 14.37%. Analysis results suggested that the viscosity reduction of heavy crude oil was caused by the destruction of structure of resin in the process of the catalytic pyrolysis reaction. [ABSTRACT FROM AUTHOR]

A transition metal oxide catalyst of copper oxide nanoparticles was synthesized by a conventional non-hydrothermal method. It was studied as a catalyst in thermocatalytic upgrading and viscosity reduction of heavy oil in the laboratory. The experimental results showed that the viscosity of heavy oil may be reduced by 85.75% with 0.2 wt% catalyst at 350 °C for 40 min. With determinations of analyzation, it was found that under the thermocatalytic action of copper oxide nanoparticles, the presence of hydrogen-donor in the reaction could further improve the chemical constitution of resin and asphaltene in heavy oil. [ABSTRACT FROM AUTHOR]

Cr3+ contained sulfuric acid aqueous solution and β-PbO2/Ti anode were prepared for electrochemical oxidation-distillation desulfurization of straight-run gasoline. Strong oxidant (Cr2O72−) was formed and reacted with organic sulfides. The oxidized sulfides were removed by distillation. Under optimal operating conditions, the desulfurization rate of gasoline reached to 99.16%.β-PbO2/Ti electrode were characterized by XRD and SEM. Model oil was analyzed by FTIR and GC-MS and the possible desulfurization mechanism was proposed. The recycling experiments of the electrolyte showed its excellent stability, but the concentration of H+ in electrolyte should be monitored, since the water will be consumed in electrolysis process, and the over-high H+ concentration is not good for the formation of Cr2O72−. [ABSTRACT FROM AUTHOR]

In this paper, choosing the mixed solution of MnSO4solution and H2SO4as electrolyte, with the progressing of electrolysis reaction, Mn3+was generated as intermediate product, combining with water to produce the oxidation agent MnOOH, which was easy to oxidize the sulfur compounds to generate sulfoxide or sulfone. At the optimal electrochemical oxidation desulfurization conditions, the sulfur content of kerosene decreased from 180 µg/g to 8.87 µg/g and the desulfurization efficiency reached to 95.07%. And the cycle of electrolyte and mechanism of electrochemical oxidation desulfurization has been discussed. [ABSTRACT FROM AUTHOR]

A novel high acid site density carbon-based solid acid catalyst was prepared and first applied in the FCC gasoline alkylation desulfurization. The catalyst was synthesized by a facile approach and characterized by X-ray powder diffraction (XRD), Fourier transform infrared (FT-IR), Brunauer–Emmett–Teller analysis (BET) and Gas Chromatography-Mass Spectrometer (GC-MS). The desulfurization performance of this solid acid catalyst was investigated and optimized. [ABSTRACT FROM PUBLISHER]

In this work we proposed a novel preparation-adsorption desulfurization method for dibenzothiophene over sawdust-derived nickel/activated carbon prepared by 400°C one step carbonization-activation-modified process. The adsorbent was characterized by X-ray Diffraction (XRD), Boehm titration method, Scanning Electron Microscope (SEM) and N2adsorption-desorption technology. The result show that 30% HNO3aqueous solution and calcination 2 h for the 30%-NiO/AC adsorbent trend to better desulfurization performance with NiO active adsorption sites and surface oxygen-containing functional groups. After high temperature adsorption desulfurization, the sawdust-derived nickel/activated carbon occurred activation and reaming again, both the specific surface and the microspore volume have been great changed. [ABSTRACT FROM PUBLISHER]

A highly efficient extractive desulfurization system with dicarboxylic acid-based deep eutectic solvents (DESs) as extractants has been developed. A series of dicarboxylic acid-based DESs were synthesized by mixing n-butylpyridinium bromide ([BPY]Br) with different dicarboxylic acids. The extraction desulfurization performance of these DESs was investigated and optimized. [ABSTRACT FROM PUBLISHER]

In situ prepared hydrophobic CuO nanoparticles, about 84.3 nm in mean diameter, was synthesized and used to catalyze heavy oil low-temperature oxidation (LTO) reaction. Experimental results showed the average oxygen consumption rate with CuO nanoparticles addition increased by 1.4 times, and the residue oxygen content in tail gas in autoclave was decreased from 8.76% to 3.9% compared to the blank experiment (without CuO nanoparticles). In addition, the CuO nanoparticles could facilitate the cleavage reaction during LTO. This study can provide guidelines to improve effectively the safety of air flooding technology in the heavy oil. [ABSTRACT FROM PUBLISHER]

Diesel with S content 624.4 µg/g was directly used, and a constant current of 500 mA was proposed in this work. Emulsification as an enhancement method was used to enhance the interphase mass transfer. After emulsifying electrochemical oxidation–extraction, the sulfur content of diesel decreased to 8.1 µg/g and the desulfurization efficiency reached 98.71 %. On comparingwith the non-emulsifying electrochemical oxidation–extraction, it has a highly efficient deep desulfurization. The analysis also found that the effect of emulsion and non-emulsion extraction desulfurization process on electrochemical oxidation has great difference under the same operating conditions, and parameters such as the order, reaction rate and activation energy of the two kinds of oxidation desulfurization reaction were studied. The results showed the oxidative desulfurization reaction is the first reaction. When the temperature reachedT2, the oxidation rate constant of the emulsion/non-emulsion system was 0.0199 min−1and 0.0179 min−1, respectively. When the temperature reachedT1, the oxidation rate constant of the emulsion/non-emulsion system was 0.0375 min−1and 0.0346 min−1, respectively. According to Arrhenius' law, the apparent activation energy of sulfur compounds in the raw oil isEa(emulsion) = 6.9783 kJ/mol andEa(non-emulsion) = 9.1826 kJ/mol, respectively. [ABSTRACT FROM AUTHOR]

Air-assisted steam flooding is a new promoting technique for enhanced oil recovery compared to the other traditional thermal recovery methods. In this study, five experiments, including one steam flooding experiment, three combined steam–air flooding experiments, and one combined steam–N2flooding experiment were studied, under the conditions of 180 °C and back-pressure valve of 8 MPa, with sand-packed model. The volume fraction of mixed gas in these four combined steam–air (or N2) flooding experiments were 80% steam+20% air, 60% steam+40% air, 40% steam+60% air, and 60% steam+40% N2, respectively. The experimental results showed that air-assisted steam flooding could enhance the oil displacement efficiency when the volume fraction of air and steam was in a certain number, and the optimal condition is 60% steam+40% air. Furthermore, water cut curves and saturate, aromatic, resin, and asphaltene (SARA) analysis results also demonstrate that the low-temperature oxidation reaction in air-assisted steam flooding process advantageous to profile control of generating high viscosity “PLUG” to seal high-permeability channel in reservoir. [ABSTRACT FROM AUTHOR]

An electrochemical oxidation−distillation method with constant current 500 mA was proposed to reduce the sulfur content in gasoline in this work. After electrochemical oxidation−distillation, the sulfur content of gasoline decreased from 514.65 to 10.20 μg/g. On the basis of these experimental results, an oxidation mechanism of electrochemical oxidative desulfurization for gasoline was proposed. [ABSTRACT FROM PUBLISHER]