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Hydrogenation and Hydrogenolysis of Olefins with Hydrogen

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Hydrogenation and Hydrogenolysis of Olefins with Hydrogen 270 石 油 学 会 誌 Sekiyu Gakkaishi, 28, (3), 270-273 (1985) Hydrogenation and Hydrogenolysis of Olefins with Hydrogen Sulfide over Sulfided Molybdena-Alumina Catalyst Masatoshi SUGIOKA* and Fujimi KIMURA Faculty of Engineering, Hokkaido University, North 13 West 8, Sapporo 060 (Received August 23, 1984) The catalytic reactions of ethylene, propylene and 1,3-butadiene with hydrogen sulfide over sulfided molybdena-alumina catalyst were examined using a closed circulation system. The hydrogenation and hydrogenolysis of ethylene and propylene proceeded in the reaction with hydrogen sulfide at 400℃. In the reaction of 1,3-butadiene with hydrogen sulfide at 200℃, the hydrogenation to form only butene isomers proceeded and the isomerization of formed butenes also occurred during the hydrogenation reaction of 1,3-butadiene. The results were interpreted in terms of hydrogen sulfide acting as hydrogen donating agent for these olefins. 1. Introduction umn and VZ-10 column. 2.2 Catalyst In the hydrodesulfurization process of heavy oil, Molybdena-alumina catalyst (MoO3 content: large amounts of hydrogen sulfide are produced, 12.5wt%) was prepared by impregnation using and these are finally converted into elementary (NH4)6Mo7O24 solution and γ-Al2O3 (JRC-ALO-4). sulfur and water by the Claus process. Since hy- The catalyst was calcined at 500℃ for 16h in air. drogen sulfide formed in the hydrodesulfurization The molybdena-alumina catalyst was evacuated at process is wasted as water, the possibility of effective 10-5 torr at 500℃ for 2h in the reactor followed usage of hydrogen sulfide would become of great by reduction with 50 torr of hydrogen at 450℃ for importance in the future petroleum industry from 2h and then sulfided with 20 torr of hydrogen an economic standpoint. Recently, some attempts sulfide at 450℃ for 2h. The sulfided molybdena- have been made on the recovery of hydrogen by alumina catalyst is represented as Mo(s)/Al2O3 in the decomposition of hydrogen sulfide over various this paper. 0.3g of the catalyst was used for the transition metal sulfides.1)-4) experiments. In this paper, we investigated the catalytic reac- 2.3 Reagents tion of some low molecular weight olefins such as High purity hydrogen(99.99999%) was provided ethylene, propylene and 1,3-butadiene with hydro- from Nippon Oxygen Co. and dried by passage gen sulfide over sulfided molybdena-alumina cat- through molecular sieve 5A cooled with liquid alyst for the purpose of effective usage of hydrogen nitrogen. Hydrogen sulfide(99.99%) was provided sulfide. from Seitetsu Chemical Co. and purified by passage through molecular sieve 5A. All olefins used in 2. Experimental this work were provided from Takachiho Chemical 2.1 Experimental Apparatus and Procedure Co. and purified by vacuum distillation before use. The catalytic reaction of olefins with hydrogen 3. Results and Discussion sulfide over sulfided molybdena-alumina catalyst was carried out in a closed circulation reactor sys- 3.1 Hydrogenation and Hydrogenolysis of tem made from pyrex glass. The dead volume of Olefins with Hydrogen Sulfide the apparatus, including the reaction vessel, was The catalytic reactions of ethylene, propylene and 385ml. The reaction products in the catalytic re- 1,3-butadiene with hydrogen sulfide over Mo(s)/ action of olefins with hydrogen sulfide were analyzed Al2O3 catalyst were examined. Fig. 1 shows the by Hitachi 023 gas chromatograph with flame reaction of ethylene with hydrogen sulfide at 400 ionization detector using propylene carbonate col- ℃. Although the conversion of ethylene was rel- * To whom correspondence should be addressed. atively low, almost equal amounts of ethane and 石 油 学 会 誌 Sekiyu Gakkaishi, Vol. 28, No. 3, 1985 271 C2H4=10 torr, H2S=14 torr 1,3-C4H6=25 torr, H2S=50 torr Fig. 1 Hydrogenation and Hydrogenolysis of Ethylene Fig. 3 Hydrogenation of 1,3-Butadiene with Hydrogen with Hydrogen Sulfide over Sulfided Molybdena- Sulfide over Sulfided Molybdena-Alumina Cat- alyst at 200℃ Alumina Catalyst at 400℃ -△-, -▽-, and -▲- represent the composition C3H6=50 torr, H2S=70 torr of butene isomers at equilibrium at 200℃ Fig. 2 Hydrogenation and Hydrogenolysis of Propylene Fig. 4 Changes in Composition of Butene Isomers in with Hydrogen Sulfide over Sulfided Molybdena- Hydrogenation of 1,3-Butadiene with Hydrogen Alumina Catalyst at 400℃ Sulfide over Sulfided Molybdena-Alumina Cat- alyst methane were formed. This indicates that both hydrogen sulfide at 200℃. The reaction of 1,3- hydrogenation and hydrogenolysis of ethylene occur butadiene with hydrogen sulfide was carried out at in the reaction of ethylene with hydrogen sulfide relatively low temperature, since the decomposition over Mo(s)/Al2O3 catalyst. and self-hydrogenation of 1,3-butadiene occurred at Fig. 2 shows the reaction of propylene with an elevated temperature. It was found that only hydrogen sulfide at 400℃. Substantial amount of hydrogenation of 1,3-butadiene to form various bu- propane and small amounts of methane and ethane tene isomers occurred at 200℃, and butane was not were formed, indicating that the main reaction of formed even after all 1,3-butadiene in gas phase propylene with hydrogen sulfide was hydrogena- had been completely consumed, which is a unique tion of propylene. After the reaction of ethylene phenomenon in the hydrogenation of 1,3-butadiene and propylene with hydrogen sulfide over Mo(s)/ with hydrogen sulfide. Fig. 4 shows the relation- Al2O3 catalyst at 400℃, the deposit of elementary ship between the conversion of 1,3-butadiene and sulfur was observed around the outlet of the reac- the composition of butene isomers formed. The tion vessel. This implies that the decomposition of composition of butene isomers depended on the hydrogen sulfide occurs during the course of the conversion of 1,3-butadiene and it attained equilib- catalytic reaction of ethylene and propylene with rium at high conversion of 1,3-butadiene, indicat- hydrogen sulfide at an elevated temperature. ing that the isomerization of butenes formed, par- Fig. 3 shows the reaction of 1,3-butadiene with ticularly, from 1-butene to trans-2-butene, also pro- 石 油 学 会 誌 Sekiyu Gakkaishi, Vol. 28, No. 3, 1985 272 ceeds during the hydrogenation of 1,3-butadiene site for the hydrogenation of olefins with hydrogen with hydrogen sulfide. sulfide over sulfided molybdena-alumina catalyst, From the experimental results in the reaction of and the hydrogenation reaction of olefins proceeds olefins with hydrogen sulfide, it was found that hy- according to the following mechanism: drogen sulfide acts as a hydrogen donating agent On the other hand, the hydrogenolysis of ethylene and the order of reactivity of olefins employed in and propylene also proceeded in the reaction of this work in the hydrogenation with hydrogen sul- these olefins with hydrogen sulfide over Mo(s)/ fide over Mo(s)/Al2O3 catalyst was ethylene<pro- Al2O3 catalyst at 400℃. It is supposed that the pylene<1,3-butadiene. 1,3-Butadiene showed the hydrogenolysis of these olefins at an elevated tem- highest reactivity in the hydrogenation with hy- perature is attributed to the attack of hydrogen drogen sulfide. This cause may be attributed to radical7) or "active hydrogen"8) formed by the de- high adsorptive ability of 1,3-butadiene in the pres- composition of hydrogen sulfide over MoS2 surface, ence of Mo(s)/Al2O3 catalyst. as the case in the liquefaction of coal with hydrogen 3.2 Catalyst Active Site and Reaction Mech- sulfide over iron sulfide catalyst.9) anism in Hydrogenation of Olefins with Hydrogen Sulfide 4. Conclusion It is generally accepted that molybdenum oxide The catalytic reactions of ethylene, propylene in the molybdena-alumina catalyst is converted into and 1,3-butadiene with hydrogen sulfide were ex- molybdenum disulfide after molybdena-alumina cat- amined over sulfided molybdena-alumina catalyst. alyst was sulfided with hydrogen sulfided5) There- The hydrogenation and hydrogenolysis of these ole- fore, it would be reasonable to assume that the fins proceeded on the sulfided molybdena-alumina reaction of olefins with hydrogen sulfide over Mo catalyst. It was concluded that hydrogen sulfide (s)/Al2O3 catalyst proceeded over MoS2 surface. acts as hydrogen donating agent in the catalytic Tanaka, et al. clarified that various coordinatively reaction with these olefins. There would be a pos- unsaturated sites exist on MoS2 surface and these sibility of the usage of hydrogen sulfide as hydrogen sites play important roles in the hydrogenation donating agent for catalytic hydrogenation and hy- and isomerization of unsaturated hydrocarbons.6) drogenolysis of other unsaturated hydrocarbons. In the previous paper4), one of the authors reported that the coordinatively unsaturated site on MoS2 References surface also serves as the active site for the catalytic 1) Fukuda, K., Dokiya, M., Kameyama, T., Kotera, Y., decomposition of hydrogen sulfide over MoS2. Ind. Eng. Chem., Fundam., 17, 243 (1978). Thus, we inferred that the coordinatively un- 2) Chivers, T., Hyne, J. B., Lau, C., Intern. J. Hydrogen Energy, 5, 499 (1980). saturated site on MoS2 surface serves as the active 3) Kiuchi, H., Iwasaki, T., Nakamura, I., Tanaka, T., ACS SymposiumSeries, No. 116, 349 (1980). 4) Sugioka, M., Aomura, K., Intern. J. Hydrogen Energy, 9, 891 (1984). 5) Gates, B. C., Katzer, J. R., Schuit, G. C. A., "Chemistry of Catalytic Process" Chap. 5 (1979), McGraw-Hill, New York. 6) Tanaka, K., Okuhara, T., Catalysis Reviews, 15, 249 (1977). 7) Stenberg, V. I., Ogawa, T., Willson, W. G., Miller, D., Fuel, 62, 1487 (1983). 8) Okutani, T., Yokoyama, S., Maekawa, Y., Furuichi, R., Ishii. T., Ind. Eng. Chem., Fundam., 22, 306 (1983). 9) Baldwin, R. M., Vinciguerra, S., Fuel, 62, 498 (1983). 石 油 学 会 誌 Sekiyu Gakkaishi, Vol. 28, No. 3, 1985 273 要 旨 硫化処理 モ リブデ ナ-ア ル ミナ触 媒上での硫化 水素によ るオ レフィンの水素化 および水素化分解 杉岡 正敏, 木村富士 巳 北海道大学工学部, 060札 幌市北区北13条 西8丁 目 硫 化 処 理 した モ リブデ ナ-ア ル ミナ 触 媒 上 で の エ チ レ ン ・プ が 生 成 す る 水 素 化 が 起 こ り, ブ タ ンは 生成 しな か った (Fig.
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