检索结果-南通市图书馆

Journal of Natural Gas Chemistry 2011年第1期20卷 65-71页

作者： Shohreh Tehrani Mohamad Irani Ahmad Tavasoli Yadollah Mortazavi Abbas A. Khodadadi Ali nakhaei Pour Research Institute of Petroleum Industry Department of Chemical Engineering College of Engineering University of Tehran School of Chemistry College of Science University of Tehran

Accelerated deactivation of ruthenium-promoted alumina-supported alkalized cobalt （K-Ru-Co/γ-Al 2 O 3 ） fischer-Tropsch （fT） synthesis catalyst along the catalytic bed over 120 h of time-on-stream （TOS） was investigated. Catalytic bed was divided into three parts and structural changes of the spent catalysts collected from each catalytic bed after fT synthesis were studied using different techniques. Rapid deactivation was observed during the reaction due to high reaction temperature and low feed flow rates. The physico-chemical properties of the catalyst charged in the Bed #1 of the reactor did not change significantly. Interaction of cobalt with alumina and the formation of CoAl 2 O 4 increased along the catalytic bed. Reducibility percentage decreased by 4.5%, 7.5% and 12.9% for the catalysts in the Beds #1, #2 and #3, respectively. Dispersion decreased by 8.8%, 14.4% and 26.6% for the catalysts in the Beds #1, #2 and #3, respectively. Particle diameter increased by 0.6%, 2.4% and 10.4% for the catalysts in the Beds #1, #2 and #3, respectively, suggesting higher rate of sintering at the last catalytic bed. The amount of coke at the last catalytic bed was significantly higher than those of Beds #1 and #2.

关键词： fischer-Tropsch synthesis cobalt accelerated deactivation sintering coke formation

A Wide Neighborhood Interior-Point Algorithm for Convex Quadratic Semidefinite Optimization

在线全文

学校读者我要写书评

暂无评论

Journal of the Operations Research Society of China 2020年第1期8卷 145-164页

作者： Mohammad Pirhaji Maryam Zangiabadi Hossien Mansouri Ali nakhaei Ali Shojaeifard Department of Mathematics and Statistics Imam Hossein Comprehensive UniversityTehranIran Department of Applied Mathematics Shahrekord UniversityShahrekordIran

In this paper,we propose an interior-point algorithm based on a wide neighborhood for convex quadratic semidefinite optimization *** the Nesterov–Todd direction as the search direction,we prove the convergence analysis and obtain the polynomial complexity bound of the proposed *** the algorithm belongs to the class of large-step interior-point algorithms,its complexity coincides with the best iteration bound for short-step interior-point *** algorithm is also implemented to demonstrate that it is efficient.

关键词： Convex quadratic semidefinite optimization feasible interior-point method Wide neighborhood Polynomial complexity

Partial oxidation of methane in Ba_(0.5)Sr_(0.5)Co_(0.8)fe_(0.1)Ni_(0.1)O_(3-δ) ceramic membrane reactor

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Natural Gas Chemistry 2012年第5期21卷 519-525页

作者： Ensieh Ganji Babakhani Jafar Towfighi Zahra Taheri Ali nakhaei Pour Majid Zekordi Ali Taheri Gas Department Research Institute of Petroleum Industry(RIPI)14665-137TehranIran Chemical Engineering Department Engineering FacultyUniversity of Tarbiat Modares14115-111TehranIran Chemistry and petrochemical Department Research Institute of Petroleum Industry(RIPI)14665-137TehranIran

Ba0.5Sr0.5Co0.8fe0.1Ni0.1O3δ（BSCfNiO） perovskite oxides were synthesized using a combined EDTA-citrate complexation method,and then pressed into disk and applied in a membrane *** performance of the BSCfNiO membrane reactor was studied for partial oxidation of methane over Ni/α-Al 2 O 3 *** time dependence of oxygen permeation rate and catalytic performance of BSCfNiO membrane during the catalyst initiation stage were investigated at 850 *** unsteady state,oxygen permeation rate,methane conversion and CO selectivity were closely related to the state of the *** 300 min from the initial time,the reaction condition reached to steady state and oxygen permeation rate were obtained about 11.7cm 3 cm 2 min ***,the performance of membrane reactor was studied at the temperatures between 750 and 950 *** results demonstrated good performance for the membrane reactor,as CH 4 conversion and CO selectivity permeation rate reached 98% and 97.5%,respectively,and oxygen permeation rate was about 14.5 cm 3 cm 2 min 1 which was 6.8 times higher than that of air-helium *** of membrane surface by SEM after reaction showed that the original grains disappeared on both surfaces exposed to the air and reaction side,but XRD profile of the polished surface membrane indicated that the membrane bulk preserved the perovskite structure.

关键词： perovskite membrane reactor partial oxidation of methane

Deactivation studies of bifunctional fe-HZSM5 catalyst in fischer-Tropsch process

在线全文

学校读者我要写书评

暂无评论

Journal of Natural Gas Chemistry 2008年第3期17卷 242-248页

作者： Ali nakhaei Pour Seyed Mehdi Kamali Shahri Yahya Zamani Mohammad Irani Shohreh Tehrani Research Institute of Petroleum Industry National Iranian Oil Company

A physical mixture of alkali-promoted iron catalyst with binder based on fischer-Tropsch synthesis and an acidic co-catalyst （HZSM5） for syngas conversion to hydrocarbons was studied in a fixed bed micro reactor. Deactivation data were obtained during the synthesis over a 1400 h period. The deactivation studies on iron catalyst showed that this trend followed the phase transformation fe2.2C （ ε′） → fe5C2 （χ） → fe3C （θ）, and the final predominant phase of the catalyst was fe3C （θ）. Deactivation of zeolite component in bifunctional catalyst may be caused by coking over the zeolitic component, dealumination of zeolite crystals, and migration of alkali promoters from iron catalyst under synthesis conditions. The deactivation rate of iron catalyst was also obtained.

关键词： catalyst deactivation fischer-Tropsch synthesis iron catalyst HZSM5 zeolite

Kinetics of the water-gas shift reaction in fischer-Tropsch synthesis over a nano-structured iron catalyst

在线全文

学校读者我要写书评

暂无评论

Journal of Natural Gas Chemistry 2010年第4期19卷 362-368页

作者： Ali nakhaei Pour Mohammad Reza Housaindokht Sayyed faramarz Tayyari Jamshid Zarkesh Department of Chemistry Ferdowsi university of Mashhad Research Institute of Petroleum Industry of National Iranian Oil Company

Based on formate and direct oxidation mechanisms,three Langmuir-Hinshelwood-Hougen-Watson （LHHW） kinetic models of the water-gasshift （WGS） reaction over a nano-structured iron catalyst under fischer-Tropsch synthesis （fTS） reaction conditions were derived and compared with those over the conventional *** conventional and nanostructured fe/Cu/La/Si catalysts were prepared by co-precipitation of fe and Cu nitrates in aqueous media and water-oil micro-emulsion,*** WGS kinetic data were measured by experiments over a wide range of reaction conditions and comparisons were also made for various rate *** rate expressions based on the formate mechanism with the assumption that the formation of formate is rate determining step were found to be the best.

关键词： kinetics water-gas-shift reaction iron catalyst fischer-Tropsch synthesis

Keplerate巨型纳米多孔聚氧钼酸盐作为可重复使用催化剂用于合成1,2,4,5-四取代咪唑(英文)

在线全文

学校读者我要写书评

暂无评论

催化学报 2014年第10期35卷 1761-1767页

作者： Ahmad nakhaei Abolghasem Davoodnia Department of Chemistry Mashhad Branch Islamic Azad University

The Keplerate‐type giant nanoporous isopolyoxomolybdate (NH4)42[MoVI72MoV60O372‐(CH3COO)30(H2O)72], denoted {Mo132}, has been used as a catalyst for the synthesis of1,2,4,5‐tetrasubstituted imidazoles by the one‐pot, four‐component thermal reaction of benzil with aromatic aldehydes, primary amines, and ammonium acetate under solvent‐free conditions. The catalyst was prepared according to a previously published literature procedure using inexpensive and readily available starting materials, and subsequently characterized by fT‐IR, UV and X‐ray diffraction spectroscopy, as well as microanalysis. The results showed that {Mo132} exhibited high catalytic activity towards the synthesis of 1,2,4,5‐tetrasubstituted imidazoles, with the desired products being formed in good to high yields. furthermore, the catalyst was recyclable and could be reused at least three times without any discernible loss in its catalytic activity. Overall, this new catalytic method for the synthesis of 1,2,4,5‐tetrasubstituted imidazoles provides rapid access to the desired compounds following a simple work‐up procedure, and avoids the use of harmful organic solvents. This method therefore represents a significant improvement over the methods currently available for the synthesis of tetrasubstituted imidazoles.

关键词：取代咪唑合成方法可重复使用纳米多孔催化剂 e型应用催化活性

Kinetics studies of nano-structured iron catalyst in fischer-Tropsch synthesis

在线全文

学校读者我要写书评

暂无评论

Journal of Natural Gas Chemistry 2010年第4期19卷 441-445页

Kinetic parameters of nano-structured iron catalyst in fischer-Tropsch synthesis （fTS） were studied in a wide range of synthesis gas conversions and compared with conventional *** conventional fe/Cu/La catalyst was prepared by co-precipitation of fe and Cu nitrates in aqueous media and fe/Cu/La nanostructure catalyst was prepared by co-precipitation in a water-in-oil ***-structured iron catalyst shows higher fTS *** results indicated that in fTS rate expression,the rate constant （k） increased and adsorption parameter （b） decreased by decreasing the catalyst particle size from conventional to *** increasing in the rate constant and decreasing in the adsorption parameter affected the fTS rate in parallel direction,the particle size of catalyst showed complicated effects on kinetic parameters of fTS reaction.

关键词： fischer-Tropsch synthesis iron-based catalyst kinetics parameters

Support effects on the chemical property and catalytic activity of Co-Mo HDS catalyst in sulfur recovery

在线全文

学校读者我要写书评

暂无评论

Journal of Natural Gas Chemistry 2010年第1期19卷 91-95页

作者： Ali nakhaei Pour Ali Morad Rashidi Kherolah Jafari Jozani Ali Mohajeri Payman Khorami Research Institute of Petroleum Industry of National Iranian Oil Company P. O. Box 114665-137 Tehran Iran

Effects of carbon nanotubes （CNT） and alumina （γ-Al2O3） supports on the catalytic activities of hydrodesulfurization （HDS） process over Co- Mo catalyst have been studied. XRD results indicated that the main active phases in CNT and γ-Al2O3 supported Co-Mo catalysts are MoO2 and MOO3, respectively. The TPR results reveal that the reduction peak temperatures of the active species on CNT supported Co-Mo catalyst is lower than those on alumina supported Co-Mo catalyst, indicating that the CNT supports favor the reduction of active species. Catalytic evaluation results displayed that the sulfur content in the reaction products on the CNT supported Co-Mo catalyst is lower than that on the alumina supported Co-Mo catalyst if the HDS reaction was carried out at a temperature above 583 K.

关键词： sulfur recovery Co-Mo catalyst carbon nanotubes HDS process

fischer-Tropsch synthesis over ruthenium-promoted Co/Al_2O_3 catalyst with different reduction procedures

在线全文

学校读者我要写书评

暂无评论

Journal of Natural Gas Chemistry 2010年第5期19卷 503-508页

作者： Ali Karimi Ali nakhaei Pour farshad Torabi Behnam Hatami Ahmad Tavasoli Mohammad Reza Alaei Mohammad Irani Research Institute of Petroleum Industry (RIPI) Gas Research Division

The effect of reduction procedure on catalyst properties, activity and products selectivity of ruthenium-promoted Co/γ-Al2O3 catalyst in fischer-Tropsch synthesis （fTS） was investigated. Catalyst samples were reduced with different reduction gas compositions and passivated before being characterized by TPR and XRD techniques. Different activity and product selectivity analyses were also performed. These results showed that the catalyst dispersion, particle size, and the degree of reduction changed with different reduction gas compositions, which were resulted from the water partial pressures in reduction process that give varying degrees of interaction with the support. It has been suggested that the fTS activity of cobalt catalyst was directly dependent on the catalyst reducibility. A reduction gas with a molar ratio of H2Prle = 1 was used to prevent the formation of Co-support compound during catalyst reduction.

关键词： fischer-Tropsch synthesis cobalt reducibility activity C5+ selectivity

Hydrocarbon production rates in fischer-Tropsch synthesis over a fe/Cu/La/Si catalyst

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2013年第1期22卷 119-129页

作者： Ali nakhaei Pour farshad Riyahi Mohammad Reza Housaindokht Mohammad Irani Seyed Mehdi Kamali Shahri Behnam Hatami Department of Chemistry Ferdowsi University of Mashhad Department of Chemical Engineering Petroleum University of Technology (PUT) Research Institute of Petroleum Industry of National Iranian Oil Company Chemical Engineering Department Penn State University University Park

The detailed kinetics of fischer-Tropsch synthesis over an industrial fe/Cu/La/Si catalyst was studied in a continuous spinning basket re- actor under the conditions relevant to industrial operations. Reaction rate equations were derived on the basis of Langmuir-Hinshelwood- Hougen-Watson type models for fischer-Tropsch synthesis based on possible reactions sets originated from the carbide, enolic and combined enol/carbide mechanisms. Kinetic model candidates were evaluated by the global optimization of kinetic parameters, which were realized by first minimization of multi-response objective functions with conventional Levenberg-Marquardt method. It was found that an enolic mech- anism based model could produce a good fit of the experimental data. The activation energy for paraffin formation is 95 ***1-1 which is smaller than that for olefin formation （121 ***-1）.

关键词： fischer-Tropsch synthesis kinetics iron catalysts catalysts selectivity