Virgin light cycle oil (LCO) derived from the FCC process containing 6090 mass ppm sulfur and 76.1 mass% aromatics, and with cetane index of 26 was refined by hydrotreatment over Ni-Mo supported catalysts in a down flow fixed-bed reactor, and the resulting LCO was hydrotreated over Pt-Pd supported catalyst in a down flow fixed-bed reactor. Ni-Mo supported silica-alumina (Ni-Mo/SA) and Ni-Mo supported alumina containing USY zeolite (Ni-Mo/USY-Al₂O₃) were used for the first hydrotreatment reaction. The double layer system of Ni-Mo/SA and Ni-Mo/USY-Al₂O₃ showed slightly better nitrogen removal activity and cetane index improvement activity at the same sulfur removal activity than the single layer system of Ni-Mo/SA, so the double layer system of Ni-Mo/SA and Ni-Mo/USY-Al₂O₃ was used for the first hydrotreatment reaction. Hydrotreated LCO using the double layer system which contained 137 mass ppm sulfur and cetane index of 32 underwent hydrotreatment over Pt-Pd supported alumina containing USY zeolite (Pt-Pd/USY-Al₂O₃). The second hydrotreatment over Pt-Pd/USY-Al₂O₃ resulted in 5 mass ppm sulfur and cetane index of 47 at hydrogen pressure 4.9 MPa, LHSV 1.0 h⁻¹, hydrogen/oil ratio 400 Nl/l and reaction temperature 320°C, which confirmed the high hydrotreatment ability of Pt-Pd/USY-Al₂O₃. Catalytic life of Pt-Pd/USY-Al₂O₃ was tested for 266 days using first hydrotreated LCO containing 137 mass ppm sulfur and cetane index of 32. Throughout the life test, sulfur content were around 10 mass ppm and and cetane index was 40. Under the same reaction conditions as the life test, another test for 42 days was carried out to examine coke deposition on Pt-Pd/USY-Al₂O₃. Coke deposition on the catalyst greatly increased towards the reactor outlet, mainly due to hydrogen reduction.

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When a matrix is saturated by a non-wetting phase, and the wetting phase fills the fracture network, capillary imbibition may occur. Capillary imbibition can be an effective recovery mechanism in water wet naturally fractured reservoirs (NFRs) where most of the oil is stored in tight matrix blocks.
This paper presents the results and analysis of the laboratory experiments with variable parameters such as oil type, rock composition, temperature, permeability, porosity and fluid that invades the matrix. To investigate temperature effect on the efficiency of capillary imbibition mechanism, capillary imbibition tests were conducted under static conditions and at different temperatures, namely 22, 50 and 80°C by using crude oils and carbonate samples taken from the same reservoirs. Also variable core sizes were used to study the block size effect on the oil recovery.
The results of static imbibition experiments show that rock and oil properties are the dominant parameters in capillary imbibition. Furthermore, increasing the operational temperature also has a positive role in the process. Therefore, in thermal EOR methods, oil recovery increases due to the enhancement of the imbibition mechanism. Also the lighter oil show high sensitivity to capillary imbibition mechanism than the heavier one and using brine instead of pure water decreased the amount of oil recovery through capillary imbibition.

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The catalytic performances of noble metals (Pt, Rh, Pd, Ru) supported on mesoporous silica MCM-41 were investigated for the hydrodesulfurization (HDS) of benzothiophene (BT). The order of HDS activities of noble metal/MCM-41 catalysts was Pt>Rh>Pd>>Ru. Pt/MCM-41 catalyst showed high HDS activity, which was higher than that of commercial CoMo/Al₂O₃ catalyst. The supported noble metal catalysts were characterized by TEM, XRD, hydrogen adsorption and benzene hydrogenation. The order of dispersion of noble metal on MCM-41 was Rh>Pt>Pd>>Ru, which was not the same as that of HDS activities. On the other hand, the order of the activities of noble metal/MCM-41 catalysts for benzene hydrogenation was Pt>Rh>Pd>Ru. The hydrogenation activity of Pt/MCM-41 catalyst was regenerated after H₂S treatment, but the activities of other catalysts were not regenerated. Thus, high hydrogenation activity and sulfur tolerance are important factors to prepare highly active noble metal/MCM-41 catalysts. Pt/MCM-41 catalyst showed remarkably high and stable activity for the HDS of BT, but Pt/SiO₂ catalyst, with similar Pt dispersion on MCM-41, showed low activity which decreased with time on stream. Since MCM-41 showed higher acidity than SiO₂, hydrogenation activity and sulfur tolerance of Pt/MCM-41 catalyst were higher than those of Pt/SiO₂ catalyst. The results of FT-IR analysis indicated that the strength of interaction between BT and MCM-41 was stronger than that of SiO₂, suggesting that both acid sites of MCM-41 and Pt particles in the Pt/MCM-41 catalyst act as active sites for the HDS of BT. Furthermore, FT-IR spectra of BT adsorbed on Pt/MCM-41 revealed that BT interacts with the silanol group on the MCM-41 surface rather than the Pt surface. Therefore, we concluded that the high HDS activity of Pt/MCM-41 catalyst could be attributed to the high hydrogenation activity of Pt and the acidity of the support.

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We aimed at precision control of the basicity of hydroxyapatite (Ca₁₀(PO₄)₆(OH)₂; HAP) and paid attention to four key factors in the synthesizing process—the solution's Ca/P ratio, pH, temperature and stirring time—and compared their influence on the Ca/P ratio and basicity of HAP. Among them, solution pH had the greatest influence on Ca/P ratio within the bulk of the catalyst. This was followed in order of influence by the Ca/P ratio of the solution (the ratio of raw materials), solution temperature and stirring time. In addition, we found that samples of HAP with the same Ca/P ratio had almost the same basic site density, even if they were synthesized using different combinations of preparation factors. This indicates that the basic site density of HAP prepared by the precipitation method depends only on the Ca/P ratio within the bulk of the catalyst.

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Selective reduction of NO using fatty acid methyl esters (FAMEs) as the reducing agents was investigated over 3 wt% Ag/Al₂O₃ catalyst. NO reduction with C₆-C₁₄ saturated FAMEs showed volcano-type temperature dependence, as NO reduction started at around 250°C, reached the maximum at around 400°C, and then decreased at higher temperatures. NO reduction efficiency increased slightly as the fatty acid chain length decreased. The efficiency of saturated FAME for selective catalytic reduction is superior to that of the corresponding unsaturated FAME. The catalysts showed stable activity at temperatures above 350°C, but deactivated with time due to coking below 300°C. The performance of selective NO reduction with saturated FAME was roughly equal to that with n-decane and n-hexadecane.

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Preparation conditions of Co-MgO catalyst for methane dry reforming were optimized to maximize the CO yield. Response surface method, composed of design of experiment and regression method, was applied. For the best regression, genetic programing, radial basis function network, and polynomial equation were compared. As a result, genetic programing succeeded to express explicitly the non-linear relationship between catalyst preparation parameters and catalyst performance, and the prediction error was the least. Genetic programing modifies and optimizes many functions by genetic algorithm to fit the experimental results. Radial basis function network could express the non-linear relationship, but the complexity of the function hindered the understanding of the importance of catalytic parameters. While polynomial equation proposed the explicit equation, the accuracy was not sufficient to show the non-linear relationship. Genetic programing is the most suitable regression method of response surface for the catalyst development.

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Catalytic degradation of low density polyethylene (LDPE) including small amounts of poly(vinyl chloride) (PVC) has been carried out to develop a chlorine tolerant catalyst for chemical recycling of waste plastics. H-galloaluminosilicate has been found to be highly active as a catalyst for converting LDPE into aromatic hydrocarbons in the presence of hydrogen chloride.

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