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مدیر دپارتمان شیمی کاربردی

[ 1 ] - تعیین سینتیک ذاتی واکنش فیشر- تروپش بر روی کاتالیست کبالت - رنیوم بر پایه ترکیبی گاما آلومینا- زیرکونیا

سینتیک ذاتی فرآیند فیشر- تروپش شامل تبدیل گاز سنتز به هیدروکربن‌های مایع و محصولات میان‌تقطیر با استفاده از کاتالیست Co-Re/Zr-Al2O3 در یک راکتور بستر ثابت به روشTaguchi مطالعه شد. تست‌های راکتوری در محدوده دمای 240-200 فشار 30-15 بار و نسبت H2/CO در محدوده 5/2-1 و میزان WHSV برابر با nL/g Cat.hr 5/1-5/0 انجام شدند. جهت ارائه مدل سینتیکی مناسب مصرف واکنش‌دهنده‌ها، نخست تعدادی مکانیسم‌ که به عنوا...

[ 2 ] - تأثیر اندازه ذرات بر عملکرد کاتالیست مولیبدن دی‌سولفید قلیایی موثر در تولید اتانول و الکل‌های سنگین از گاز سنتز

کاتالیست‌های مولیبدن قلیایی با درصد مولیبدن 5/2 ، 5، 10، 15 و 20 و نسبت مولیبدن به پتاسیم 875/1 بر روی نانو لوله‌کربنی جهت بررسی عملکرد کاتالیست با تغییر اندازه ذرات به روش تلقیح سنتزشدند. کاتالیست‌ها در oC 330و 18 بار در حضور هیدروژن و مونوکسیدکربن (نسبت 2 به1)، جهت سنتز الکل‌ها تست شدند. محصولات جمع‌آوری شده توسط دستگاه کروماتوگرافی گازی آنالیز شدند. کاتالیست‌ها با روش‌های BET ، TPR، XRD ، H2...

[ 3 ] - سنتزو بکارگیری نانو کاتالیزورPt-Re/Al2O3موثردر فرایند رفورمینگ نفتا

اثر روش سنتز نانوکاتالیست بر خواص شیمی-فیزیکی و عملکرد ¬نانوکاتالیست دوفلزی پلاتین-رنیم بر پایه آلومینا بررسی شد. نمونه های نانوکاتالیست با استفاده از روش میکروامولسیون سنتز شده وکارایی آنها با کاتالیست ساخته شده به روش تلقیح در رفورمینگ نرمال هپتان در دمای°C 500 و فشارatm1مقایسه گردید. خواص فیزیکی و شیمیایی کاتالیستها با روش¬های جذب و واجذب نیتروژن، ICP واحیای برنامه¬ریزی¬شده دمایی (TPR) تعیین...

[ 4 ] - Molybdenum Loading Effects on the Physico-Chemical Properties and Performance of Carbon Nanotubes Supported Alkalized MoS2 Catalysts for Higher Alcohols Synthesis

An extensive study of Higher Alcohols Synthesis (HAS) from syngas using alkalized MoS2 catalysts supported on Carbon Nanotubes (CNTs) is reported. Up to 30wt.% of Mo and 8wt.% K are added to the CNTs by impregnation method. The catalysts were characterized by different methods and the performance of the catalysts was assessed in a micro-reactor. TEM images showed that mo...

[ 5 ] - Cobalt Loading Effects on the Physico-Chemical Properties and Performance of Co Promoted Alkalized MoS2/CNTs Catalysts for Higher Alcohols Synthesis

An extensive study of Higher Alcohol Synthesis (HAS) from synthesis gas using cobalt (Co) promoted alkalized MoS2 catalysts supported on Carbon NanoTubes (CNTs) is reported. Up to  5wt.% of Co is added to the 15wt.% Mo-wt.%K/ CNTs by incipient wetness impregnation method. Most of the metal particles were homogeneously distributed inside the tubes and the rest on the oute...

[ 6 ] - Deactivation Behavior of Carbon Nanotubes Supported Cobalt Catalysts in Fischer-Tropsch Synthesis

The effects of electronic properties of inner and outer surfaces of Carbon Nano Tubes (CNTs) on the deactivation of cobalt Fischer-Tropsch (FT) catalysts were studied. The comparative characterization of the fresh and used catalysts by TEM, XRD, TPR, BET and H2 chemisorption showed that cobalt re-oxidation, cobalt-support interactions and sintering are the main sources o...

[ 7 ] - Effects of Confinement in Carbon Nanotubes on the Performance and Lifetime of Fischer-Tropsch Iron Nano Catalysts

The effects of confinement in carbon nanotubes on Fischer-Tropsch (FT) activity, selectivity and lifetime of Carbon NanoTubes (CNTs) supported iron catalysts are reported. A method was developed to control the position of the catalytic sites on either inner or outer surface of carbon nanotubes. TEM analyses revealed that more than 80% of iron oxide particles can be controlled to be position...

[ 8 ] - Investigating the Effects of Mass Transfer and Mixture Non-Ideality on Multiphase Flow Hydrodynamics Using CFD Methods

A numerical framework has been proposed to model the interacting effects of mixture non-ideality and mass transfer on hydrodynamics of a multiphase system using CFD methods.Mass transfer during condensation and vaporization is modeled by chemical potential at the liquid-vapor interface. Species mass transfers are related to the diffusion at the interface which in turn is related to the conc...

[ 9 ] - Preparation of a Novel Super Active Fischer-Tropsch Cobalt Catalyst Supported on Carbon Nanotubes

The potential of carbon nanotubes (CNT) supported cobalt catalysts for Fischer-Tropsch (FT) reaction is shown. Using the wet impregnation method cobalt on carbon nanotubes catalysts were prepared with cobalt loading varying from 15 to 45 wt. %. The catalysts are characterized by different methods including: BET physisorption, X-ray diffraction, hydrogen chemisorption, and temperature-progra...

[ 10 ] - Raising Distillate Selectivity and Catalyst Life Time in Fischer-Tropsch Synthesis by Using a Novel Dual-Bed Reactor

In a novel dual bed reactor Fischer-Tropsch synthesis was studied by using two diffrent cobalt catalysts. An alkali-promoted cobalt catalyst was used in the first bed of a fixed-bed reactor followed by a Rutenuim promoted cobalt catalyst in the second bed. The activity, product selectivity and accelerated deactivation of the system were assessed and compared with a conventional single bed r...

[ 11 ] - Cobalt Loading Effects on the Structure and Activity for Fischer-Tropsch and Water-Gas Shift Reactions of Co/Al2O3 Catalysts

An extensive study of Fischer-Tropsch synthesis (FTS) on alumina-supported cobalt catalysts with different amounts of cobalt is reported. Up to 40 wt % of cobalt, is added to the catalysts by impregnation method. The effect of the cobalt loading on the reducibility of the cobalt oxide species, dispersion of the cobalt, average clusters size, water-gas shift (WGS) activity and activity and s...

[ 12 ] - Accelerated Deactivation and Activity Recovery Studies of Ruthenium and Rhenium Promoted Cobalt Catalysts in Fischer-Tropsch Synthesis

Accelerated deactivation of Co/Al2O3 catalysts in Fischer-Tropsch synthesis and the effect of Re and Ru as the catalytic promoters are reported. 15wt% Co/Al2O3 catalyst and 1wt% Ru and 1.4wt% Re  promoted cobalt catalysts have been formulated and extensively characterized. The deactivation of the unpromoted cobalt catalyst and those promoted with ...

[ 13 ] - Effects of Different Loadings of Ru and Re on Physico-Chemical Properties and Performance of 15% Co/Al2O3 FTS Catalysts

An extensive study of Fischer-Tropsch synthesis (FTS) on alumina-supported cobalt catalysts promoted with different amounts of ruthenium and rhenium is reported. Up to 2 wt% of promoters, are added to the catalyst by coimpregnation. The catalysts are characterized by different methods including: BET physisorption, X-ray diffraction, hydrogen chemisorption, and temperature-programmed reducti...

[ 14 ] - Production of Hydrogen and Synthesis gas via Cu-Ni/Al2O3 catalyzed gasification of bagasse in supercritical water media

Bagasse as a real biomass was converted to hydrogen rich gas via catalytic supercritical water gasification process. To find the effect of Cu on selectivity of products, Cu promoted Ni-γAl2O3 catalysts were prepared with 1 to 20wt% Ni and 0.5 to 10wt% Cu loadings via impregnation method. Catalysts were characterized by ICP, BET, XRD, H2 chemisorption and TEM technique as well CHNS analysis was ...

[ 15 ] - Surface chemistry improvement of carbon nanotube (CNT) supported Fischer–Tropsch nanocatalysts

Functionalization of carbon nanotube (CNT) was performed, during preparation of Fischer–Tropsch synthesis (FTS) via cobalt nanocatalysts, to modify the surface properties of CNT support. Common and functionalized CNT supported cobalt nanocatalysts were prepared using impregnation wetness method with cobalt loading of 15 wt.%. The catalysts were characterized by Brunauer–Emmett–Teller (BET), Fou...

[ 16 ] - Size-dependent Kinetics Determination of MoS2-K2O/CNTS Nanocatalyst in the Synthesis of Alcohols from Syngas

The influence of Mo particle size on the catalytic activity and product selectivity of alkalized MoS2 nanocatalysts has been investigated. Nanocatalysts are prepared using a microemulsion technique with water-to-surfactant ratios of 1-12. Three different techniques, including XRD, TEM, and hydrogen chemisorption were used to determine the molybdenum average particle size and their activity and ...

[ 17 ] - بهینه سازی عملکرد و پایداری کاتالیست کبالت بر پایه نانو ورقه های گرافنی در سنتز فیشر تروپش

کاتالیست کبالت بر پایه نانو ورقه های گرافنی در سنتز فیشر تروپش استفاده شده است. ساخت کاتالیست به روش تلقیح مرطوب با میزان بارگذاری 15% از فلز کبالت انجام شده است.خواص شیمیایی و فیزیکی کاتالیست با تست های ویژگی سنجی مختلف از جمله TPR, TPD, XRD, TEM, BET و غیره مورد بررسی قرار گرفت. عملکرد کاتالیست در میکرو راکتور بستر ثابت در دمای 220 درجه سانتی گراد و فشار 18 بار و نسبت H2/CO برابر با 2 بررسی ش...

[ 18 ] - بررسی اثر بهبود دهنده ها و هم افزایی آن ها در نانوکاتالیست کبالت برپایه نانولوله های کربنی جهت کاربرد در واکنش فیشرتروپش

کاتالیست های کبالت بر پایه‏ ی CNT با بهبود دهنده ­های Ca، Ce،KوZr ساخته شد.  سپس افزودن همزمان این بهبود دهنده ­ها به صورت Ca/Ce  وK/Zr  با روش تلقیح صورت گرفت و اثر هم ­افزایی یک بهبود دهنده‏ ی قلیایی، قلیایی خاکی با یک بهبود دهند...