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期刊论文 18

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丙烯 2

Au/Ti双功能催化剂 1

H2有效利用率 1

三元乙丙橡胶 1

丙烯环氧化 1

偕胺肟型螯合树脂 1

催化裂解 1

吉布斯能 1

多不饱和脂肪酸 1

多元醇 1

密度泛函理论 1

异丁烯 1

材料科学 1

核辐射技术 1

橡胶籽油 1

环氧化 1

相平衡计算方法 1

石油化学工业 1

碳化硅陶瓷纤维 1

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Effect of triethylamine treatment of titanium silicalite-1 on propylene epoxidation

Juan XU,Yaquan WANG,Wenping FENG,Yi LIN,Shuhai WANG

《化学科学与工程前沿(英文)》 2014年 第8卷 第4期   页码 478-487 doi: 10.1007/s11705-014-1453-7

摘要: Titanium silicalite-1(TS-1) treated with triethylamine (TEA) solution under different conditions was characterized by X-ray powder diffraction (XRD), Fourier-transform infrared spectrum (FTIR), ultraviolet-visible diffuse reflectance spectrum (UV-Vis), nitrogen physical adsorption and desorption, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The characterization results show that many irregular hollows are generated in the TS-1 crystals due to the random dissolution of framework silicon and the volume of the hollow cavities increase with increasing the TEA concentration, and the treatment temperature and time. The modified TS-1 samples improved in varying degrees the catalyst life for the epoxidation of propylene in a fixed-bed reactor probably due to the generation of the hollows to make it easy for the reactants and products to diffuse out of the channels.

关键词: titanium silicalite-1     triethylamine     hollow cavity     epoxidation of propylene     catalyst life    

Controllable synthesis of a large TS-1 catalyst for clean epoxidation of a C=C double bond under mild

《化学科学与工程前沿(英文)》 2023年 第17卷 第6期   页码 772-783 doi: 10.1007/s11705-022-2280-x

摘要: Development of a titanium silicalite-1 (TS-1) catalyst with good crystallinity and a four-coordinate Ti framework is critical for efficient catalytic oxidation reaction under mild conditions. Herein, a size-controlled TS-1 zeolite (TS-1#0.1ACh (acetylcholine)) was synthesized via steam-assisted crystallization by introducing acetylcholine as a crystal growth modifier in the preparation process, and TS-1#0.1ACh was also employed in epoxidations of different substrates containing C=C double bonds. The crystalline sizes of the as-synthesized TS-1#0.1ACh catalysts were controlled with the acetylcholine content, and characterization results showed that the particle sizes of highly crystalline TS-1#0.1ACh zeolite reached 3.0 μm with a good Ti framework. Throughout the synthetic process, the growth rate of the crystals was accelerated by electrostatic interactions between the connected hydroxyl groups of the acetylcholine modifier and the negatively charged skeleton of the pre-zeolites. Furthermore, the TS-1#0.1ACh catalyst demonstrated maximum catalytic activity, good selectivity and high stability during epoxidation of allyl chloride. Importantly, the TS-1#0.1ACh catalyst was also highly versatile and effective with different unsaturated substrates. These findings may provide novel, easily separable and large TS-1 catalysts for efficient and clean industrial epoxidations of C=C double bonds.

关键词: size-controlled TS-1     crystal modifier     steam-assisted crystallization     epoxidation    

Selective epoxidation of linear terminal olefins with metalloporphyrins under mild conditions

Xiaoguang BAI, Yuanbin SHE

《化学科学与工程前沿(英文)》 2009年 第3卷 第3期   页码 310-313 doi: 10.1007/s11705-009-0168-7

摘要: The epoxidation of linear terminal olefins with metalloporphyrins in the presence of dioxygen and isobutyraldehyde under ambient temperature and atmospheric pressure was investigated. The results show that all olefins could be smoothly converted to epoxides with high selectivities (70%-90%). For the metalloporphyrins with different catalytic activities within 1-hexene epoxidation in the order of Fe>Mn>Co, T( -Cl)PPFe(Ⅲ)Cl was most effective, with a 41.7% yield and 80.2% selectivity of 1,2-epoxyhexane. Various amounts of catalyst were investigated, and it was found that with only 10 ppm catalyst the yield of 1,2-epoxyhexane and turnover number (TON) could reach up to 41.9% and 41859, respectively.

关键词: metalloporphyrins     olefins     dioxygen     epoxidation    

Deactivation and regeneration of TS-1/SiO

Hainan SHI, Yaquan WANG, Guoqiang WU, Wenping FENG, Yi Lin, Teng ZHANG, Xing JIN, Shuhai WANG, Xiaoxue WU, Pengxu YAO

《化学科学与工程前沿(英文)》 2013年 第7卷 第2期   页码 202-209 doi: 10.1007/s11705-013-1328-3

摘要: TS-1/SiO catalyst for the epoxidation of propylene with hydrogen peroxide in a fixed-bed reactor has been investigated. The catalyst activity decreases gradually with the online reaction time, but the selectivity of propylene epoxide is kept at about 93%. The fresh, deactivated and regenerated catalysts were characterized with X-ray diffraction, Fourier transform infrared spectroscopy, ultra-violet-visible diffuse reflectance, Brunner-Emmett-Teller method and thermogravimetric analysis, and the deactivated catalyst was regenerated with H O /methanol solution. Compared with the fresh catalyst, both the framework structure and the content of titanium in the framework of the deactivated and regenerated TS-1/SiO catalysts were not changed. The major reason of the catalyst deactivation was the blockage of the channels of the catalyst by bulky organic by-products, which covered the active centers of titanium in TS-1. The deposited materials on the deactivated TS-1/SiO catalyst could be removed by treatment with hydrogen peroxide/methanol solution or pure methanol; the higher the treatment temperature and the higher the concentration of H O in methanol, the higher the extent of the regeneration. The regeneration treatment did not influence the product selectivity in the propylene epoxidation.

关键词: TS-1/SiO2     epoxidation of propylene     fixed-bed reactor     deactivation     regeneration    

Alkylation of benzene with propylene catalyzed by FeCl3-chloropyridine ionic liquid

SUN Xuewen, ZHAO Suoqi, LI Hui

《化学科学与工程前沿(英文)》 2007年 第1卷 第3期   页码 292-295 doi: 10.1007/s11705-007-0053-1

摘要: Alkylation of benzene with propylene was carried out with FeCl3-chloro-butyl-pyridine (FeCl-[bpc]) ionic liquid as catalyst to obtain cumene. Significant improvements in propylene conversion and cumene selectivity under mild reaction conditions were attained by modification of the catalyst with HCl. Under 20ºC, 0.1 MPa, reaction time 5 min, mole ratio of benzene to propylene 10:1 and mass ratio of FeCl-[bpc] to benzene 1:100, conversion of propylene can increase from 83.60% to 100.00% and selectivity of cumene can increase from 90.86% to 98.47%. If reaction is carried out in following two stages, the result will be very good. At the initial stage of the reaction, alkylation is the main reaction and a higher conversion of propylene is obtained at a lower temperature. At the later stage of the reaction, transalkylation is the main reaction and selectivity to cumene can be increased by appropriately raising the reaction temperature.

Polyethylene glycol-supported ionic liquid as a highly efficient catalyst for the synthesis of propylene

Rui YAO, Hua WANG, Jinyu HAN

《化学科学与工程前沿(英文)》 2012年 第6卷 第3期   页码 239-245 doi: 10.1007/s11705-012-1297-y

摘要: The coupling reaction of propylene and CO to form propylene carbonate (PC) was promoted by an ionic liquid (IL) covalently bound to polyethylene glycol (PEG). The supported ionic liquid, which has both acidic and basic components, proved to be an active catalyst for PC synthesis under mild conditions. The effects of different cations and anions, reaction temperature, CO pressure, and reaction time were investigated. It was demonstrated that the acid group in the catalyst plays an important role in the reaction. With this system, a high PC yield (95%) was achieved under mild conditions (3.0 MPa, 120°C and 4 h) without a co-solvent. In addition, the catalyst was readily recovered and reused. Based on the experimental results, a plausible mechanism for the catalyst was proposed.

关键词: ionic liquid     PEG-supported ionic liquid     carbon dioxide     propylene carbonate    

Methanol to propylene: the effect of iridium and iron incorporation on the HZSM-5 catalyst

Alireza MOHAMMADREZAEI, Sadegh PAPARI, Mousa ASADI, Abas NADERIFAR, Reza GOLHOSSEINI

《化学科学与工程前沿(英文)》 2012年 第6卷 第3期   页码 253-258 doi: 10.1007/s11705-012-0902-4

摘要: The effect of iridium and iron impregnation of HZSM-5 zeolite on the methanol to propylene reaction (MTP) was investigated. The selectivities of propylene and other hydrocarbons, and the conversion of methanol were compared by performing MTP in a small pilot plant. The results indicate that HZSM-5 zeolite modified by iron and iridium increased propylene selectivity by 6.3% and 8%, respectively. The selectivity of propylene was higher for Ir/H-ZSM-5 than for Fe/H-ZSM-5, where Fe/H-ZSM-5 was more stable than Ir/H-ZSM-5. Analytic techniques, including X-ray diffraction, BET surface area, temperature-programmed desorption of ammonia, and inductively coupled plasma atomic emission spectroscopy, were used to characterize the modified zeolites as well as the parent zeolites.

关键词: HZSM-5     promoter     iridium     iron     MTP    

Synthesis of magnetic Pb/Fe

Hualiang AN, Xinqiang ZHAO, Zhiguang JIA, Changcheng WU, Yanji WANG

《化学科学与工程前沿(英文)》 2009年 第3卷 第2期   页码 215-218 doi: 10.1007/s11705-009-0055-2

摘要: To facilitate the recovery of Pb/SiO catalyst, magnetic Pb/Fe O /SiO samples were prepared separately by emulsification, sol-gel and incipient impregnation methods. The catalyst samples were characterized by means of X-ray diffraction and N adsorption-desorption, and their catalytic activity was investigated in the reaction for synthesizing propylene carbonate from urea and 1,2-propylene glycol. When the gelatin was applied in the preparation of Fe O at 60°C and the pH value was controlled at 4 in the preparation of Fe O /SiO , the Pb/Fe O /SiO sample shows good catalytic activity and magnetism. Under the reaction conditions of a reaction temperature of 180°C, reaction time of 2 h, catalyst percentage of 1.7 wt-% and a molar ratio of urea to PG of 1∶4, the yield of propylene carbonate attained was 87.7%.

关键词: Pb/Fe3O4/SiO2 magnetic particle     urea     1     2-propylene glycol     propylene carbonate    

Poly(vinylidene fluoride--hexafluoro propylene) membranes prepared via thermally induced phase separation

《化学科学与工程前沿(英文)》 2022年 第16卷 第5期   页码 720-730 doi: 10.1007/s11705-021-2098-y

摘要: A non-toxic and environmentally safe diluent, acetyl tributyl citrate, was employed to prepare poly(vinylidene fluoride)-co-hexafluoropropylene membranes via thermally induced phase separation. Effects of the polymer concentration on the phase diagram, membrane morphology, hydrophobicity, pore size, porosity and mechanical properties (tensile stress and elongation at break) were investigated. The results showed that the pore size and porosity tended to decrease with increasing polymer concentration, whereas the contact angle, liquid entry pressure and mechanical properties showed the opposite trend. In direct contact membrane distillation operation with 3.5 wt-% sodium chloride solution as the feed solution, the prepared membranes performed high salt rejection (>99.9%). Furthermore, the prepared membranes retained excellent performance in long-term stability tests regarding the permeate flux and salt rejection.

关键词: poly(vinylidene fluoride)-co-hexafluoropropylene     thermally induced phase separation     non-toxic diluent     direct contact membrane distillation    

Impact of dimethyl ether on engine seal materials

WU Ning, ZHANG Wugao, HUANG Zhen

《能源前沿(英文)》 2008年 第2卷 第3期   页码 279-284 doi: 10.1007/s11708-008-0042-1

摘要: The resistance of many kinds of rubber materials to dimethyl ether (DME) was studied. Both the mass and volume change of rubber materials, which were put in DME and then exposed to the air for different periods of time were measured. The results show that fluorine rubber (FKM), silicone rubber (SIR), and nitrile rubber (NBR) are unsuitable as seal materials for DME engines. Common polyvinylchloride (PVC) dissolved completely in DME, which has almost no impact on vulcanizing nylon material. The constitution of ethylene propylene terpolymer rubber (EPDM) has a major impact on its resistance to DME. A kind of EPDM with good resistance to DME was found, whose reliability was validated by 100 hours of DME engine operation.

关键词: impact     Common polyvinylchloride     different     constitution     ethylene propylene    

橡胶籽油中多不饱和脂肪酸的分离及其环氧化反应研究

黄元波,杨晓琴,杨静,郑云武,郑志锋

《中国工程科学》 2014年 第16卷 第4期   页码 74-78

摘要:

对橡胶籽油(rubber seed oil,RSO)中的多不饱和脂肪酸(polyunsaturated fatty acid,PUFA)进行了分离纯化,以此为原料,采用过氧乙酸原位法合成了环氧化多不饱和脂肪酸并进行了红外分析,探讨了30 %过氧化氢(H2O2)的用量、冰乙酸的用量、反应时间和反应温度对环氧化反应的影响。结果表明,当原料与30 % H2O2用量比为1∶2.5(质量比)、与冰乙酸的用量比为1∶0.9(质量比),在65 ℃下反应3 h,环氧化程度最高,产物环氧值可达8.28 mol/100 g,相对环氧转化率为82 %,双键转化率为97 %。

关键词: 橡胶籽油     多不饱和脂肪酸     环氧化     多元醇    

, phase morphologic, thermal and mechanical properties of poly(trimethylene terephthalate)/ethylene propylene

RUN Mingtao, SONG Hongzan, WANG Yingjin, YAO Chenguang, GAO Jungang

《化学科学与工程前沿(英文)》 2007年 第1卷 第3期   页码 238-245 doi: 10.1007/s11705-007-0043-3

摘要: The rheological, phase morphologic, thermal and mechanical properties of poly(trimethylene terephthalate)/metallocene polyethylene (PTT/mPE) blends in the presence of ethylene propylene diene monomer copolymer grafted with maleic anhydride (EPDM--MAH) as compatibilizer are studied by means of a capillary rheometer, scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and thermogravimetric analyzer (TGA). Results suggest that the compatibility of PTT/mPE blends is improved greatly after the addition of a compatibilizer. The radius of the dispersed phase in the system decreases greatly when the compatibilizer is added into the blend. When the amount of compatibilizer exceeds 8 wt-%, the size of dispersed phase becomes larger again. This phenomena could be attributed to the higher viscosity of the EPDM--MAH phase, which is dispersed more difficulty in the PTT phase of lower viscosity, thus the mixing efficiency is apparently decreased during the melt blending process. Moreover, the melt viscosity of the blend reaches the maximal value in case of 4 wt-% compatibilizer content, above which it would decrease again. This result is associated with the generation of more and bigger dispersed phase inside the bulk phase, thus the grafting efficiency at the interface is decreased, which could result in lower viscosity. The DSC results suggest that the mPE component shows a nucleating effect, and could increase the overall degree and rate of PTT crystallization, while the addition of a compatibilizer might slightly diminish these effects. In addition, the blend with 4 wt-% compatibilizer shows the best thermal stability. Furthermore, the Izod impact strength and the tensile strength at room temperature of the blend are also markedly improved by the addition of a 4 8 wt-% compatibilizer.

关键词: /metallocene polyethylene     presence     rheological     phenomena     trimethylene terephthalate    

Application of metal magnetic memory test in failure analysis and safety evaluation of vessels

Yiliang ZHANG, Song YANG, Xuedong XU

《机械工程前沿(英文)》 2009年 第4卷 第1期   页码 40-48 doi: 10.1007/s11465-009-0003-3

摘要: Metal magnetic memory test (MMMT), which is a new subject in the field of nondestructive examination, can determine regions of stress concentration by testing the distribution of the magnetic field of metal structures so as to effectively diagnose premature defects. MMMT and other test methods are applied in the study to put a propylene purifier of a temperature-jump accident and a leaked ammonia vessel through safety evaluation. Results are as follows: The margin of safety declines after the purifier is overburnt; several stress concentrations are observed within the overburnt area and the level of stress concentration rises after one-month operation; and overpressure operation of the purifier must be strictly avoided and carefully monitored during later operation. Cracks are observed on the ammonia vessel after one year’s service. Extremely high residual stress is the primary cause of cracks. After four years in service, the residual stresses existing in the area of the base metal and weld zone are still greater than 0.5 , which results in numerous cracks due to stress corrosion. From the MMMT result of the ammonia vessel’s defects, it can be seen that the derivative of magnetic density (d p/d ) is an important reference variable. Within the 31 leakage points, 67.7% of them whose dHp/dx values are more than 10, and 96.8% of them whose dHp/dx values are more than 8.

关键词: Metal magnetic memory test (MMMT)     nondestructive testing (NDT)     residual stress     propylene purifier     ammonia vessel    

催化裂解架起了炼油与化工之间的桥梁

李再婷

《中国工程科学》 1999年 第1卷 第2期   页码 67-71

摘要:

催化裂解是以石油中的重油为原料,用催化方法生产丙烯等基本有机化工原料的技术。在世界上我国首先研究开发了此新工艺及催化剂,并于1990年成功进行了工业示范。迄今,国内外已有七套应用该技术的工业装置建成并投产。生产的丙烯等化工原料已分别用来合成了高质量的聚丙烯、聚乙烯及丙烯腈等化学品。目前催化裂解已可应用更重质的原料,如常压渣油,并开发出能适合不同原料的多种催化剂。文中重点介绍了应用该技术在泰国建成的一套催化裂解装置的生产情况。

关键词: 催化裂解     石油化学工业     丙烯     异丁烯    

局部面积搜索法在高压相平衡中的应用

郭继志,刘涛,袁渭康

《中国工程科学》 2001年 第3卷 第3期   页码 56-60

摘要:

用最小Gibbs 能曲线积分的正面积最大方法(AM)进行相平衡的计算和预测,可以比传统的闪蒸计算法更好地计算高压下和近临界区的相平衡组成。但是这一方法由于使用了在全组成范围的"穷举"方法搜索最大正面积对应的相平衡组成,使得收敛速度慢,计算和搜索时间过长;将其修改成多次局部面积搜索法(LSAM),极大提高了收敛速度和减少了计算时间,并利用所测定的苯与丙烯高压平衡数据对其进行了有效性检验。

关键词: 吉布斯能     高压汽液平衡     相平衡计算方法         丙烯    

标题 作者 时间 类型 操作

Effect of triethylamine treatment of titanium silicalite-1 on propylene epoxidation

Juan XU,Yaquan WANG,Wenping FENG,Yi LIN,Shuhai WANG

期刊论文

Controllable synthesis of a large TS-1 catalyst for clean epoxidation of a C=C double bond under mild

期刊论文

Selective epoxidation of linear terminal olefins with metalloporphyrins under mild conditions

Xiaoguang BAI, Yuanbin SHE

期刊论文

Deactivation and regeneration of TS-1/SiO

Hainan SHI, Yaquan WANG, Guoqiang WU, Wenping FENG, Yi Lin, Teng ZHANG, Xing JIN, Shuhai WANG, Xiaoxue WU, Pengxu YAO

期刊论文

Alkylation of benzene with propylene catalyzed by FeCl3-chloropyridine ionic liquid

SUN Xuewen, ZHAO Suoqi, LI Hui

期刊论文

Polyethylene glycol-supported ionic liquid as a highly efficient catalyst for the synthesis of propylene

Rui YAO, Hua WANG, Jinyu HAN

期刊论文

Methanol to propylene: the effect of iridium and iron incorporation on the HZSM-5 catalyst

Alireza MOHAMMADREZAEI, Sadegh PAPARI, Mousa ASADI, Abas NADERIFAR, Reza GOLHOSSEINI

期刊论文

Synthesis of magnetic Pb/Fe

Hualiang AN, Xinqiang ZHAO, Zhiguang JIA, Changcheng WU, Yanji WANG

期刊论文

Poly(vinylidene fluoride--hexafluoro propylene) membranes prepared via thermally induced phase separation

期刊论文

Impact of dimethyl ether on engine seal materials

WU Ning, ZHANG Wugao, HUANG Zhen

期刊论文

橡胶籽油中多不饱和脂肪酸的分离及其环氧化反应研究

黄元波,杨晓琴,杨静,郑云武,郑志锋

期刊论文

, phase morphologic, thermal and mechanical properties of poly(trimethylene terephthalate)/ethylene propylene

RUN Mingtao, SONG Hongzan, WANG Yingjin, YAO Chenguang, GAO Jungang

期刊论文

Application of metal magnetic memory test in failure analysis and safety evaluation of vessels

Yiliang ZHANG, Song YANG, Xuedong XU

期刊论文

催化裂解架起了炼油与化工之间的桥梁

李再婷

期刊论文

局部面积搜索法在高压相平衡中的应用

郭继志,刘涛,袁渭康

期刊论文