Prediction of the effects of asphaltene deposition on oil reservoir parameters during water flooding was investigated in two scenarios of oil production wells with controlled oil rate and controlled bottomhole flow pressure of the producer well. The effects of asphaltene deposition on average reservoir pressure, cumulative oil production, and water breakthrough in the first scenario were predicted. Then the effects of asphaltene deposition on average reservoir pressure, bottomhole pressure in the oil production well, and water breakthrough in the second scenario were assessed. The network model results were incorporated into a three-dimensional, three-phase black oil simulator, BOAST, from the US Department of Energy. The asphaltene deposition effect on oil reservoir performance was evaluated using reported experimental data including oil and water relative permeability and the calculated network modeling results including capillary pressure during imbibition. The experimental data were related to the actual conditions of reservoir fluids, and flow through actual carbonate cores under similar reservoir conditions of temperature and pressure. Three different asphaltene contents of crude oil from the UAE were investigated.

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The organic hydride method utilizes the reversible hydrogenation-dehydrogenation cycle of aromatic hydrocarbons for the storage and transportation of hydrogen. If low-grade hydrogen containing CO impurity is used in the hydrogenation process, storage and purification of hydrogen can be attained simultaneously. This study investigated the effect of Pd on SiO₂, Al₂O₃ and SiO₂-Al₂O₃ catalyst supports on the hydrogenation of naphthalene in the presence of CO. Pd/Al₂O₃ catalyst had the highest activity for hydrogenation using pure hydrogen. However, Pd/SiO₂-Al₂O₃ showed the highest activity using 2%CO/H₂. All catalysts allowed only the hydrogenation of naphthalene to proceed and no CO hydrogenation was observed. CO probe FT-IR spectra were observed at elevated temperatures. Desorption behavior was dependent on the catalysts and, especially on the lower wavenumber side, strongly adsorbed CO changed more significantly with the catalyst. CO desorption behavior of Pd/SiO₂-Al₂O₃ indicated weak Pd-CO bond. Deconvolution of the IR spectra showed that the acidity of the SiO₂-Al₂O₃ support decreased the electron density of Pd, resulting in weakening of the Pd-CO bond, which promoted the high hydrogenation activity in the presence of CO.

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Fischer-Tropsch syntheses were carried out in a slurry phase over Mn-modified Ru/carbon nanotube (CNT) catalysts using hexadecane as a solvent. CO conversion and C₅₊ selectivity were dependent on the Ru and Mn concentrations as well as the reaction temperature. The activity of the catalyst containing optimized amounts of Ru and Mn was very similar to that of Ru-Mn/γ-Al₂O₃, although the initial activity of CNT-based catalysts after 3 h was about 10% lower than that of Al₂O₃-based catalyst. Presumably removal of chloride from RuCl₃ to form active metallic ruthenium species on the CNT catalyst was enhanced by the addition of manganese.

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Adsorption of sulfur oxide is one of the key techniques for producing extra-low-sulfur content naphtha during oxidative desulfurization. Reactivation and repeated use of adsorbent are quite important for practical and economic reasons. The reactive performance of silica gel (SIL), an excellent adsorbent for the adsorption of benzothiophene-1,1-dioxide (BTDO), a model sulfur oxide, was evaluated using toluene and dimethyl ether (DME) by multicycle adsorption-reactivation tests. In an 8-cycle adsorption-reactivation test using toluene as a reactivation agent, the breakthrough amount after 8 cycles was reduced to 68% of the first cycle. Using DME, the breakthrough amount was reduced to 87% at the second run based on the first run, but this level was maintained throughout the remaining cycles. Three types of naphtha, Naphtha A, hydrotreated naphtha (Naphtha B), and a 50% mixture, were tested in 8-cycle tests using DME as a reactivation agent. The breakthrough amount of SIL was as high as 1300-1700 g/g-SIL for Naphtha A, and 500-1000 g/g-SIL for Naphtha B containing 13 wt% of aromatics. The breakthrough amount for the mixture was almost the same as for Naphtha A. These results suggest that SIL is suitable for naphtha containing up to 7 wt% of aromatics. A 25-cycle adsorption-reactivation test was performed using Naphtha A by limiting the throughput to 1300 g/g-SIL. During the 25 cycles, no significant amount of BTDO was observed in any of the treated naphtha products.

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[Additions]
Fig.1 ⁷⁾, Fig.2 ⁷⁾, Fig.3 ⁷⁾, Fig.4 ⁷⁾, Fig.5 ⁷⁾, Fig.6 ⁷⁾
Fig.7 ¹⁰⁾, Fig.8 ¹⁰⁾, Fig.9 ¹⁰⁾, Fig.10 ¹⁰⁾, Fig.11 ¹⁰⁾
Fig.12 ¹³⁾, Fig.13 ¹³⁾, Fig.14 ¹³⁾, Fig.15 ¹³⁾, Fig.16 ¹³⁾
Fig.17 ¹⁵⁾, Fig.18 ¹⁵⁾, Fig.19 ¹⁵⁾, Fig.20 ¹⁵⁾
Fig.21 ¹⁶⁾, Fig.22 ¹⁶⁾, Fig.23 ¹⁶⁾, Fig.24 ¹⁶⁾, Fig.25 ¹⁶⁾
Fig.26 ¹⁸⁾

[Corrections]
(wrong) Table 9 ¹⁷⁾ (correct) Table 9 ¹⁸⁾
(wrong) Table 10 ¹⁷⁾ (correct) Table 10 ¹⁸⁾

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