Yihong Liu

Reaction Kinetics of Transesterification between Vegetable Oil and Methanol under Supercritical Conditions

Abstract The dynamic transesterification reaction of peanut oil in supercritical methanol media was investigated. The reaction temperature and pressure were in the range of 250°C–310°C and 10.0 MPa–16.0 Mpa, respectively. The molar ratio of peanut oil to methanol was 1:30. It was found that the yield of methyl esters was higher than 90% under the supercritical methanol. The apparent reaction order and activation energy of transesterification was 1.5 and 7.472 kJ/mol, respectively. In this method, the reaction time was shorter and the processing was simpler than that of the common acid catalysis transesterification.

Removal of Naphthenic Acids of a Second Vacuum Fraction by Catalytic Esterification

Abstract This article introduces a catalytic esterification process to reduce the acid number of a high acid content petroleum fraction. The fraction was treated with methanol under conditions sufficient to form the naphthenic acid esters. In this way, the acid number of the petroleum fraction could be lowered. SnO could accelerate petroleum oil esterification. The acid removal ratio was much higher in the presence of SnO than without it. The optimal reaction conditions were: reaction temperature 300°C, the quantity of methanol in oil was 5.0 wt%, the quantity of catalyst SnO was 4.0 wt%, and a longer reaction time was preferable.

Adsorption Desulphurization of Gasoline by Silver Loaded onto Modified Activated Carbons

The removal of organosulphur from gasoline by adsorption onto commercial carbon samples loaded with different amounts of silver nitrate was investigated. The pore structures of the samples were characterized by nitrogen adsorption studies, while the structure and chemical property of the samples before and after adsorption were examined and analyzed by XRD, FT-IR and SEM methods, respectively. The results showed that silver formed π-complexes with organic sulphides; the higher the silver loading, the greater the amount adsorbed. However, the adsorption selectivity was poor.

Hydrocracking Gudao Residual Oil Using Supercritical Water-Syngas as Hydrogen Source in Suspension Bed. Part III: Water-Gas Shift Reaction

Abstract The catalytic hydroconversion of Gudao residue in supercritical water-syngas system is a heavy oil upgrading technology. The hydrogen derived from water-gas shift reaction can be used for residue hydrocracking, so, it is important for studying the water-gas shift reaction that takes place in the hydrocracking system. Here, the water-gas shift reaction in the supercritical water-syngas system was investigated. The results showed that the water-gas shift reaction could be effectively increased with dispersed catalysts, and more than 80% CO was conversed in the initial processes.

The Mechanism of Diesel Hydrogenation Using Supercritical Water-Syngas

Abstract Many reactions were involved in the diesel hydrorefining processes in the supercritical water-syngas system, as the mechanism of diesel hydrogenation using supercritical water-syngas was investigated by using isotopic D2. The 2H-NMR results of hydrogenated products revealed that the supercritical water-syngas could be used as an alternative hydrogen source for diesel hydrotreating because much higher deuterium content appeared in the products. The results also indicated that the hydrogen derived from supercritical water-syngas could exchange the sulfur, so hydrogen was added to the diesel molecule.

Adsorption of Methylene Blue in Acoustic and Magnetic Fields by Porous Carbon Derived from Sewage Sludge

After KOH activation, the pyrolysis residues of sewage sludge could be converted to a porous carbon with a pore size situated mainly in the 0.6–1.5 nm range. The adsorption rate and capacity of the porous carbon towards Methylene Blue could be improved by the use of acoustic and magnetic fields. The best adsorption behaviour was displayed when the acoustic field frequency was 50 Hz and the magnetic field strength was 485 mT.

The Pyrolysis of Buton Oil Sands and Its Kinetics

Abstract In this article, the pyrolysis characteristics and kinetics of oil sands from Buton, Indonesia were investigated. The results show that Buton oil sand has high oil content, analyzed by Fischer assay analysis and Dean-Stark extraction, and a retorting temperature of which should be controlled at 480–500°C. Differential thermal analysis was used to investigate pyrolysis kinetics and weight loss occurring mainly from 280 to 480°C, which is similar to that of Fischer assay analysis. The apparent activation energy, E, of samples is about 190 kJ·mol−1, which is calculated by the maximum pyrolysis rate method. Researches show that Buton oil sands application is a good prospect.

Regeneration of Used Lubricating Oils by Supercritical Fluid Extraction

Abstract Regeneration of used lubricating oils by supercritical fluid extraction were investigated. The broken-down additives and impurities were removed by the high selectivity of supercritical fluid, and high-quality lube oil was obtained. Corrosion and waste-disposal problems produced by older acid-clay process have been lessened.

Extraction of Sulfur-containing Compounds from Diesel by 1-Ethyl-3-methylimidazolium Diethyl Phosphate in a Lab-scale Extractive Column

Desulfurization of diesel using 1-ethyl-3-methylimidazolium diethyl phosphate in a lab-scale extractive column was investigated to explore a deep desulfurization process that could be used as a supplemental technology to hydrodesulfurization. The results showed that the dibenzothiophene derivatives could be removed by extraction with 1-ethyl-3-methylimidazolium diethyl phosphate, the extraction sulfur-containing components increase with the mass ratio of 1-ethyl-3-methylimidazolium diethyl phosphate to diesel, and lower viscosity could also result in the higher desulfurization result. Optimum feed rate and an appropriate extraction temperature were needed to ensure the desulfurization effect. Extraction yield of sulfur-containing compounds followed the order of C2-DBT > DBT > C1-DBT > 4-MDBT > 4,6-DMDBT > -C2-BT > C2-BT > C3-BT.