CIMS论文的天地_其他论文_免费提供学术论文全文

由于此栏目中论文数量过多，不方便查找，所以本站将其进行了分类，点击查看其他分类论文。

局部加热对重质油加氢裂化的影响
（下载论文全文请点击上面的链接）
注意：本论文已在《石油化工》2002,31（11）:871-874发表
使用者请注明论文出处

常杰1，椿范立2，藤元薰2
(1．中国科学院广州能源研究所，广东广州 5l0070；2．日本东京大学，东京113-8656)

摘要：采用间歇式高压釜反应器研究了加拿大油砂沥青和沙特重质减压渣油及其模型化合物十二烷基苯的加氢裂化反应，实验条件为5.0MPa、410—430℃、0-60min。以微小电热丝在反应器中很小的区域制造了局部高温，考察了其对加氢裂化的影响。结果表明，该方法促进了反应物中自由基的形成，提高了重质油及其模型化合物的转化率和中间馏分油的收率
关键词：重质油；加氢裂化；自由基

Effect of Local Heating on Hydrocracking of Heavy Oils

CHANG Jie1, TSUBAKI Noritasu2,FUJIMOTO Kaoru
（1.Guanghou Institute of Energy Conversion, Chiese Academy of Sciences, Guangzhou Guangdong, 510070,China 2.Department of Applied Chemistry, University of Tokyo, Tokyo 113-8656, Japan）

Abstract: Hydrocracking tests of Canadian oil sand bitumen, Saudi Arabian heavy vacuum residue and model compound 1 -pheny1 dodecane (PhDD) were carried out in a batch autoclave reactor. The reaction conditions were as follows: pressure 5.0 MPa, temperature 410-430℃, reaction time 0-60 min. The heating with a fine inside filament produced small local high temperature zone in the reaction, its effect on the hydrocracking was investigated. Results show that this method accelerates the formation of free radicals, improves the conversion of heavy oil and its model compound, and increases the yield of the middle fraction oil.
Key Words: heavy oil; hydrocracking; free radical

Jie Chang（常杰）, Noritatsu Tsubaki, Kaoru Fujimoto
（Department of Applied Chemistry, School of Engineering, The University of Tokyo, Hongo 7-3-1, Tokyo 113-8656, Japan）

Abstract: The effect of element sulfur on the conversion of residue for catalytic hydrocracking of Arabian heavy vacuum residue was tested using an autoclave reactor. The reaction condition was 703K and 0.5MPa of hydrogen partial pressure. Adding only a small amount of sulfur increased the conversion of residue from 64 to 80 wt%, as well as the yield of middle distillate from 23 to 31 wt%. This should be attributed to the free-radical initiation effect of sulfur. Sulfur promoted the decomposition of residue at the catalytic hydrocracking condition.
Key Words: Sulfur; Hydrocracking; Conversion; Vacuum residue

Kinetics of resid hydrotreating reactions
（下载英语论文全文请点击上面的链接）
注意：本论文已在《Catalysis Today》1998,43:233-239发表
使用者请注明论文出处

Jie Chang*（常杰）, Jiansheng Liu, Dadong Li
Research Institute of Petroleum Processing (PIPP) P.O. Box 914-17, Beijing, 100083, China

Abstract: Five resids from the Middle East and China have been hydrotreated in a pilot plant, which has three Æxed-bed reactors in series. Six commercial catalysts were tested. The process conditions were 12.0±16.8 MPa, 370±405℃, LHSVof 0.15±1.0 hˇ1, H2/oil ratio of 400±1000 nm3 mˇ3. The feedstocks included the following Chinese resids Shengli, Xinjiang and Liaohe. Kinetic parameters of resid hydrotreating reactions were calculated in terms of pore diffusion resistance and were correlated with some special properties of oils and catalysts. This study supplies important basic data for the selection of catalysts, for the design of composite catalyst beds and for the optimization of process conditions.
Keywords: Kinetics; Reaction; Hydrotreating; Resid

生物质废弃物制氢技术
（下载论文全文请点击上面的链接）
注意：本论文已在《环境保护
吕鹏梅，常杰，熊祖鸿，吴创之，陈勇
(中国科学院广州能源研究所，广州 510070)

摘要：本文介绍了利用生物质废弃物和微生物制氢的几种技术，分析了每种技术的制氢原理、制氢效益和发展状况；并提出生物质催化气化制氢是实现能源结构转变及环境保护的有效手段，是很有前景的一种生物质废弃物制氢方法。
关键词：生物质制氢催化气化

Jie Chang（常杰）, Li Fan and Kaoru Fujimoto
Department of Applied Chemistry, School of Engineering, The University of Tokyo

Introduction
　　With growing worldwide demand for transport fuels and other middle distillates, much attention has been paid to the upgrading of heavy oil feedstock. It was forecasted that up to early 2000, the petroleum product slate will continue to shift from fuel oil to transportation fuels, distillate and jet will be the products with the strongest growth, and the conversion will be increased worldwide to meet this trend (Sonnemans, 1995).　 Based on cracking mechanism, there are three main industrial processes to produce middle distillate from resid, thermal cracking, catalytic cracking and hydrocracking. Hydro-thermal cracking, the combination of thermal cracking and catalytic hydrogenating, is a novel method developed by Fujimoto laboratory to upgrade resids aiming at maximum middle distillate (Fujimoto et al., 1988; Aimoto et al., 1991; Yang et al., 1998). The following elementary steps are important during hydro-thermal cracking reactions: (1) Initiation free radical (homolytic cleavage of a hydrocarbon molecule into two free radicals). (2) Free radical dissociation (βscission). (3) Hydrogen transfer (between H2, radical and hydrocarbon). H transfer from H2 to radical may suppress the secondary cracking of hydrocarbon. It was supposed that some effective initiators could probably enhance the conversion of resids by increasing the concentration of free radicals. Much research has been carried out on catalyst development, reaction mechanism, process design and optimization in the above refinery processes in the last half century. But the issue of adding initiators in the cracking of resids was very rarely addressed. The present work showed the promotional effect of initiators in hydro-thermal cracking of resids and its model compound.

Jie Chang（常杰）, Li Fan, and Kaoru Fujimoto
Department of Applied Chemistry, School of Engineering, The University of Tokyo

ABSTRACT: The conversions of heavy oil and its model compound were remarkably enhanced by adding peroxide during hydro-thermal cracking. The reaction mechanism on model compound, n-dodecylbenzene, suggested that the hydrogen in hydrocarbon was easily abstracted by free radical formed from decomposition of peroxide and the chain reactions were readily initiated. Therefore, the conversion was obviously increased even at lower temperature.

HYDROTHERMAL CRACKING OF RESIDUAL OILS
（下载英语论文全文请点击上面的链接）
注意：本论文已在《Sekiyu Gakkaishi (J. Japan Petrol. Inst.)》 43 (1), pp.25. 发表
使用者请注明论文出处

Noritatsu TSUBAKI, Jie CHANG（常杰）, and Kaoru FUJIMOTO
Department of Applied Chemistry, School of Engineering, The University of Tokyo
7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, JAPAN

INTRODUCTION
With the growing demand for high quality transportation fuels and middle distillate products, to obtain high conversion from heavy oil and bitumen is becoming the predominant research target of resid upgrading processes. Hydrothermal cracking has been developed to obtain maximum middle distillate yield (kerosene + gas oil) from residual oil [1-3]. It involves free radical chain reactions and catalytic hydrogenation reactions: (1) C-C and C-X (heteroatom) bonds rupture to produce free radicals; (2) free radical dissociation to produce low-boiling products; (3) catalytic hydrogenation to terminate radicals, remove heteroelements and saturate C-C bonds such as olefin and aromatic etc [4-5].
The decomposition of resid is thermodynamically favored at high reaction temperature. With the increase of temperature, the selectivity of by-products, coke and gaseous hydrocarbon, will be increased, and therefore the selectivity of middle distillate will be lowered. How to obtain high conversion at low reaction temperature is the key point to resolve this contradiction. According to the mechanism of free radical chain reactions, some effective initiators may enhance the conversion of residue by increasing the concentration of free radicals. The present work showed the effect of the addition of free radical initiators, di-tert-butyl-peroxide (DTBP) and sulfur, on the decomposition of resids and model compound. Both remarkably enhanced the conversion of heavy oil.

Jie CHANG（常杰）, Noritatsu TSUBAKI*, and Kaoru FUJIMOTO
Department of Applied Chemistry, School of Engineering, The University of Tokyo,
Hongo 7-3-1, Bunkyo-ku, Tokyo, 113-8656, Japan

Abstract: Hydrothermal cracking of Canadian Athabasca bitumen was performed over Ni/SiO2 and Ni/Al2O3 catalysts under 703 K and 5.0 MPa of hydrogen pressure in a batch reactor. Comparing with thermal cracking under the same reaction conditions, hydrothermal cracking process obviously suppressed the formation of coke from 5.5wt% to 3.5wt% (Ni/SiO2) and to 3.0wt% (Ni/Al2O3), and the formation of gaseous hydrocarbon products. To decrease coke formation further, a small amount of potassium was impregnated in the catalysts. The spectroscopy of NH3-TPD showed that the amount of acidic sites in both catalysts, Ni/Al2O3 and Ni/SiO2, was dramatically decreased by K2O modification. The acid-catalyzed polymerization of residuum induced by acidic sites in the catalyst, that might result in the formation of coke, was suppressed by neutralization of the acidic sites. Adding 3% of potassium onto Ni/SiO2 decreased the yield of coke from 3.5wt% to 2.1wt%.
Keywords: Hydrothermal process, Catalyst modification, Acidity, TPD

Jie Chang（常杰）, Noritatsu Tsubaki* and Kaoru Fujimoto
Department of Applied Chemistry, School of Engineering, The University of Tokyo,

Masao Yoshimoto Petroleum Energy Center of Japan, KSP R&D Build. D-12-1237, 3-2-1, Sakado, Takatsu-ku, Kawasaki, Kanagawa, 213-0012, Japan

The upgrading of heavy oils is attracting growing interest as a means of producing premium quality transportation fuels and other middle distillate products. Hydro-thermal cracking is one of the promising processes to obtain maximum middle distillate (kerosene + gas oil) from residual oils. This process and its reaction mechanism have been described elsewhere.1,2 Hydro-thermal cracking of resid, which is the combination of thermal cracking and catalytic hydrogenation, is composed of the following elementary steps: (1) formation of free radicals proceeding via cleavage of C-C or C-X (heteroatom) bond;3,4 (2) production of middle distillate proceeding via β-scission of free radicals;5 (3) termination of free radical reactions and saturation of C=C bonds proceeding via catalytic hydrogenation.
High reaction temperature can simply accelerate the conversion of resid, but the selectivities of gaseous hydrocarbons and coke will be increased tremendously. We have demonstrated that adding some initiators, such as element sulfur and di- tert-butyl-peroxide, which might produce free radicals even at lower temperature, promoted the conversion of resids and increased the yield of distillate.2,6 This paper presents our results on another initiation method, local heating by inside filament. The in situ measurement of free radical concentration during hydro-thermal cracking of Kuwait AR was carried out by ESR and reported elsewhere.7 The in situ spin concentration (at g = 2.0035, which shows the signal of hydrocarbon free radical) was detected by using a quartz tube containing Kuwait AR at 2.0 MPa of hydrogen pressure and heating it at 5 K/min. The results showed that the spin concentration of free radicals increased with the increasing temperature probably due to the cleavage of C-C and C-S bond and leveled off at about 480 K, then it slightly decreased, and again increased very quickly at above 680 K. According to this trend, an inside filament was employed to realize higher-temperature zone at some limited space inside the reactor to initiate the formation of free radicals at lower reaction temperature. The experiment results proved that local heating effectively promoted the conversion of Canadian oil sand bitumen and Arabian VR.

注意：本论文已在《Sekiyu Gakkaishi (J. Japan Petrol. Inst.) 》 43 (6), pp. 414. 发表
使用者请注明论文出处

Jie CHANG†1)（常杰）, Noritatsu TSUBAKI†1)*, Kaoru FUJIMOTO†1) and Masao YOSHIMOTO†2)
†1) Dept. of Applied Chemistry, School of Engineering, The University of Tokyo,
Hongo 7-3-1, Bunkyo-ku, Tokyo, 113-8656, JAPAN
†2) Petroleum Energy Center of Japan, KSP R&D Build. D-12-1237, 3-2-1, Sakado,
Takatsu-ku, Kawasaki, Kanagawa, 213-0012, JAPAN

During the hydrothermal cracking of hydrocarbon and heavy oil catalyzed by Ni/Al2O3, the conversions of hydrocarbon and heavy oil were remarkably enhanced by heating with a small inside filament. The experiment facts suggested that the heating with inside filament might realize higher temperature zone at local space in the reactor, which was responsible for an increase of the concentration of free radicals, and enhanced the conversion of hydrocarbons even at lower temperature.
Keywords: Hydrothermal process, Hydrocarbon, Heavy oil, Initiation, Filament