检索结果-南通市图书馆

Modeling of microreactor for syngas production by catalytic partial oxidation of methane

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6期19卷 660-668页

作者： akbar zamaniyan Alireza Behroozsarand Hamid Mehdizadeh Hussein Ali Ghadirian Department of Natural Gas Conversion Gas Research DivisionResearch Institute of Petroleum Industry (RIPI)Tehran 14665-1998Iran Department of Chemical Engineering Islamic Azad UniversityIlkhchi BranchIlkhchiTabriz 53581-1148Iran Department of Chemical Engineering NTNUTrondheimNO-7491Norway

Fixed-bed reactors for the catalytic partial oxidation of methane （CPOM） to produce synthesis gas still pose hot spots *** is a good alternative reactor proposed to resolve these *** this paper,synthesis gas （hydrogen and carbon monoxide） production was investigated by a two-dimensional numerical model of single *** fluid dynamic （CFD） modeling with detailed chemistry was conducted to understand the CPOM on platinum （Pt） *** inlet velocity,microchannel pressure,and fuel to air ratio （F/A） are selected as the effective parameters on microchannel *** results show that Reynolds number has considerable effect on methane conversion,hydrogen to carbon monoxide ratio （H2/CO）,and product *** gas inlet velocity causes all the above parameters to *** is noted that increasing microchannel pressure and decreasing the ratio of fuel to air cause the decrease of the H2/CO ratio.

关键词： synthesis gas microchannel catalytic partial oxidation of methane reynolds number

Effect of Sintering Temperature on Microstructure and Hydrogen Permeation Properties of Perovskite Membrane

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2013年第2期29卷 137-141页

作者： Marzieh Heidari akbar zamaniyan Aliakbar SafeKordi Ensieh Ganji Babakhani Mahdi Amanipour Chemical Engineering Department Sharif University of Technology Gas Department Research Institute of Petroleum Industry

The BaCe0.9Y0.1O3-δ （BCY） perovskite membrane was successfully synthesized by liquid citrate method. The phase structure of the powder was characterized by X-ray diffraction （XRD）. Scanning electron microscopy （SEM） was used to characterize microstructures of the membrane sintered under various conditions. Sintering temperatures and dwell time during sintering influence the final microstructure of the ceramic. Results showed that increasing sintering temperature resulted in a dense membrane with clear grains. An increase of dwell time was favorable to produce membranes with larger grains in the sintered ceramics. A density of 5.87 g/cm3 was reached for the membrane after sintering at 1200 ℃ with dwell time of 10 h. This resulted in the formation of dense membranes with clear structure and average grain size of 0.27 μm. The influence of microstructure on the hydrogen permeation flux through BCY was observed by measuring the hydrogen permeation flux, and the results showed that hydrogen permeation flux increases with increasing the average grain size of the membrane. From H2 permeation rates, it was found that bulk diffusion rather than surface reaction played the dominant role in H2 transport.

关键词： Ceramic membrane Perovskite Sintering Microstructure Hydrogen permeation

Structure Stability and Oxygen Permeability of Perovskite-type Oxides of Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.1)R_(0.1)O_ (3-δ)(R=Al,Mn,Fe,Ce,Cr,Ni,Co)

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2012年第2期28卷 177-183页

作者： Ensieh Ganji Babakhani Jafar Towfighi Laleh Shirazi Ali Nakhaeipour akbar zamaniyan Zahra Shafiei Gas Department Research Institute of Petroleum Industry (RIPI) Chemical Engineering Department Engineering FacultyUniversity of Tarbiat Modares

Perovskite-type a0.5Sr0.5Co0.8Fe0.1R0.1O3-δ （R=Al, Mn, Fe, Ce, Cr, Ni, Co） oxide membranes were ex- ploited and synthesized. Oxygen behavior, order-disorder transition and phase stability of these composite oxides were investigated by combined analysis of X-ray diffraction （XRD）, temperature programmed desorp- tion （TPD）, thermogravimetric-differential thermal analysis （TG-DTA）. Oxygen permeation through these membranes was studied by the gas chromatography （GC） method using a high-temperature permeation cell in a wide temperature range from 700 to 950℃. High permeation fluxes were observed for these materials. The high permeation flux was about 3.19 ***-2 under air/He gradients at 950℃, which was achieved for a0.5Sr0.5Co0.8Fe0.1R0.1O3-δ（BSCFNiO） membrane. The results of analysis showed no phase transition for BSCFNiO oxide with increasing temperature and XRD pattern of this material after O2-TPD indicated to sustain a pure perovskite structure after oxygen permeation process.

关键词： Perovskite Ceramic membrane Oxygen separation Phase stability

Effect of mass transfer limitations on catalyst performance during reduction and carburization of iron based Fischer-Tropsch synthesis catalysts

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2013年第5期22卷 795-803页

作者： akbar zamaniyan Yadollah Mortazavi Abbas Ali Khodadadi Ali Nakhaei Pour Department of Natural Gas Conversion Gas Research Division Research Institute of Petroleum Industry (RIPI) School of Chemical Engineering University College of Engineering University of Tehran

Existence of intraparticle mass transfer limitations under typical Fischer-Tropsch synthesis has been reported previously,but there is no suitable study on the existence of intraparticle diffusion limitations under pretreatment steps (reduction and activation) and their effect on catalytic performance for iron based *** this study,Fe-Cu-La-SiO2 catalysts were prepared by co-precipitation *** investigate the intraparticle mass transfer limitation under reduction,activation and reaction steps,and its effect on catalytic performance,catalyst pellets with different sizes of 6,3,1 and 0.5 mm have been *** catalysts were calcined,pretreated and tested under similar *** catalysts were activated in hydrogen (5%H2in N2) at 450℃ for 3 h and exposed to syngas (H2/CO=1) at 270℃ and atmospheric pressure for 40 ***,FTS reaction tests were performed for approximately 120 h to reach steady state conditions at 290℃,17 bar and a feed flow (syngas H2/CO=1) rate of 3 L/h (STP).Using small pellets resulted in higher CO conversion,FT reaction rate and C5+ productivity as compared with larger *** small pellets reached steady state conditions just 20 h after starting the *** for larger pellets,CO conversion,FT reaction rate and C5+ productivity increased gradually,and reached steady state and maximum values after 120 h of *** results illustrate that mass transfer limitations exist not only for FTS reaction but also for the reduction and carburization steps which lead to various phase formation through catalyst *** the results indicate that some effects of mass transfer limitations in activation step,can be compensated in the reaction *** results can be used for better design of iron based catalyst to improve the process economy.

关键词： Fischer-Tropsch mass transfer limitation activation catalyst GTL