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Turkish Journal of Electrical Engineering and Computer Sciences
No abstract provided.
Optimal Location For Shunt Connected Facts Devices In A Series Compensated Long Transmission Line, P.R. Sharma, Ashok Kumar, Narender Kumar
Optimal Location For Shunt Connected Facts Devices In A Series Compensated Long Transmission Line, P.R. Sharma, Ashok Kumar, Narender Kumar
Turkish Journal of Electrical Engineering and Computer Sciences
Shunt FACTS devices are used for controlling transmission voltage, power flow, reducing reactive losses, and damping of power system oscillations for high power transfer levels. In this paper the optimal location of a shunt FACT device is investigated for an actual line model of a transmission line having series compensation at the center. Effect of change in degree of series compensation on the optimal location of the shunt FACTS device to get the highest possible benefit is studied. It is found that the optimal location of the shunt FACTS device varies with the change in the level of series compensation …
A New Relaying Algorithm To Detect Loss Of Excitation Of Synchronous Generators, Ömer Usta, M. H. Musa, M. Bayrak, M.A. Redfern
A New Relaying Algorithm To Detect Loss Of Excitation Of Synchronous Generators, Ömer Usta, M. H. Musa, M. Bayrak, M.A. Redfern
Turkish Journal of Electrical Engineering and Computer Sciences
A new digital relaying algorithm is introduced for the protection of synchronous generators against loss of excitation conditions. The new algorithm is based on measuring of the 3-phase reactive power output of the machines, and monitors the direction and magnitude of leading reactive power at the generator terminal. The protection algorithm is designed such that it can provide reliable protection against loss of field conditions and remains stable during recoverable power system swing conditions. While the new relay produces a trip signal for partial loss of field conditions causing the machine to lose its stability, it remains stable for the …
A Sensitive Ann Based Differential Relay For Transformer Protection With Security Against Ct Saturation And Tap Changer Operation, Hassan Khorashadi Zadeh, Zuyi Li
A Sensitive Ann Based Differential Relay For Transformer Protection With Security Against Ct Saturation And Tap Changer Operation, Hassan Khorashadi Zadeh, Zuyi Li
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents an artificial neural network (ANN) based scheme for fault identification in power transformer protection. The proposed scheme is featured by the application of ANN to identifying system patterns, the unique choice of harmonics of positive sequence differential currents as ANN inputs, the effective handling of current transformer (CT) saturation with an ANN based approach, and the consideration of tap changer position for correcting secondary CT current. Performance of the proposed scheme is studied for a wide variety of operating conditions using data generated from simulation. The results indicate that the proposed scheme provides a fast and sensitive …
Study Of The Warranty Cost Model For Software Reliability With An Imperfect Debugging Phenomenon, D.R. Prince Williams
Study Of The Warranty Cost Model For Software Reliability With An Imperfect Debugging Phenomenon, D.R. Prince Williams
Turkish Journal of Electrical Engineering and Computer Sciences
Software reliability is one of the most important characteristics of software quality. Its measurement and management technologies employed during the software life-cycle are essential for producing and maintaining quality/reliable software systems. Herein, we discuss a modified approach to calculating the delivery cost of a software product, when warranty is to be provided, with an imperfect debugging phenomenon. Unlike existing cost models, here the strategy was to consider maintenance support given to the customer with an imperfect debugging phenomenon. The optimal release time can be calculated for various reliability levels by minimizing the cost. The delivery cost, reliability of the software …
Synthesis And Characterization Of Polyimides Prepared From Optically Active (R,R) And (S,S)-1,3-Bis(P-N,N´-Dimethylaminobenzyl)-Perhydrobenzimidazol-2-Thion, Murat Yi̇ği̇t, Turgay Seçki̇n, Süleyman Köytepe, Engi̇n Çeti̇nkaya
Synthesis And Characterization Of Polyimides Prepared From Optically Active (R,R) And (S,S)-1,3-Bis(P-N,N´-Dimethylaminobenzyl)-Perhydrobenzimidazol-2-Thion, Murat Yi̇ği̇t, Turgay Seçki̇n, Süleyman Köytepe, Engi̇n Çeti̇nkaya
Turkish Journal of Chemistry
This paper presents the synthesis and characterization of polyimides containing a chiral (R,R) or (S,S) 1,3-bis(p-N,N´-dimethylaminobenzyl)-perhydrobenzimidazol-2-thion unit in the backbone. The reactions occur between equimolar amounts of a dianhydride and an aromatic dimethylamine in the presence of the solvent N-methyl-2-pyrollidone (NMP). In this work, the chiral monomer RR and SS -1,3-bis(p-N,N´-dimethylaminobenzyl)-perhydrobenzimidazol- 2-thion were used as diamines. The polyimides obtained were characterized by thermogravimetry (TGA), differential thermal analysis (DTA), differential scanning calorimeter (DSC), infrared spectroscopy (FT-IR), and gel permeation chromatography (GPC). It was found that the composition of the polymer had a significant effect upon the thermal behavior of the material.
On-Line Preconcentration And Speciation Of Chromium By An 8-Hydroxyquinoline Microcolumn Immobilized On Surfactant-Coated Alumina And Flow Injection Atomic Absorption Spectrometry, Seyyed Hamid Ahmadi, Ali Mohammad Haji Shabani, Shayessteh Dadfarnia, Masoumeh Taei
On-Line Preconcentration And Speciation Of Chromium By An 8-Hydroxyquinoline Microcolumn Immobilized On Surfactant-Coated Alumina And Flow Injection Atomic Absorption Spectrometry, Seyyed Hamid Ahmadi, Ali Mohammad Haji Shabani, Shayessteh Dadfarnia, Masoumeh Taei
Turkish Journal of Chemistry
An on-line technique for the determination of chromium species with atomic absorption spectrometry is described. The method is based on separation and preconcentration of Cr(III) on a microcolumn of immobilized 8-hydroxyquinoline on surfactant-coated alumina. The adsorbed analyte is then eluted with 400 \mu L of 20% ethanolic solution of 1.5 mol L^{-1} hydrochloric acid and is transported to a flame atomic absorption spectrometer for quantification. The effects of pH, sample and eluent flow rate, sorption capacity, and the presence of various cations and anions on the sorption of Cr(III) were investigated. The sorption was quantitative in the pH 6-8 range, …
Synthesis And Physico-Chemical And Spectroscopic Investigations Of Sodium Dihydrobis(1,2,3-Benzotriazolyl)Borate Ligand And Its Transition Metal Complexes, . Lutfullah, Ahmad Umar, Mohammed Muzibur Rahman, Mohammad Mansoob Khan, Yoon Bong Hahn
Synthesis And Physico-Chemical And Spectroscopic Investigations Of Sodium Dihydrobis(1,2,3-Benzotriazolyl)Borate Ligand And Its Transition Metal Complexes, . Lutfullah, Ahmad Umar, Mohammed Muzibur Rahman, Mohammad Mansoob Khan, Yoon Bong Hahn
Turkish Journal of Chemistry
The title ligand, sodium dihydrobis(1,2,3-benzotriazolyl)borate, Na[H_2B(BTz)_2], was synthesized by refluxing 1 mole of sodium borohydride with 2 moles of 1,2,3- benzotriazole in toluene. The ligand shows ample reactivity towards Cr(III), Mn(II), Fe(III), Fe(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Hg(II) metal ions and forms stable complexes. The ligand and its metal complexes were characterized by physico-chemical and spectroscopic techniques. All the complexes of divalent metal ions are tetrahedral except for Cu(II), which has been proposed to have a square-planar geometry. The complexes of Cr(III) and Fe(III) appear to have an octahedral geometry. The magnitude of molar conductance of 10^{-3} M …
Hydrothermal Synthesis, Characterization And Photocatalytic Activity Of Nanosized Tio_2 Based Catalysts For Rhodamine B Degradation, Funda Sayilkan, Meltem Asi̇ltürk, Şadi̇ye Şener, Sema Erdemoğlu, Murat Erdemoğlu, Hi̇kmet Sayilkan
Hydrothermal Synthesis, Characterization And Photocatalytic Activity Of Nanosized Tio_2 Based Catalysts For Rhodamine B Degradation, Funda Sayilkan, Meltem Asi̇ltürk, Şadi̇ye Şener, Sema Erdemoğlu, Murat Erdemoğlu, Hi̇kmet Sayilkan
Turkish Journal of Chemistry
Nanosize crystalline TiO_2 and SiO_2/TiO_2 mixed oxide particles as a photocatalyst for rhodamine B dye (RB) degradation in aqueous media were synthesized by a hydrothermal process at 200 °C. They were characterized using XRD, SEM, FT-IR, UV/VIS and BET analysis. The effects of silica content on the crystallinity and photocatalytic activity of TiO_2 were investigated. Photocatalytic activity of the nano-TiO_2 was compared with that of SiO_2/TiO_2 mixed oxides at the same conditions for degradation of RB, and mixed oxide catalysts showed more effective catalytic activity than the TiO_2. The results revealed that photodegradation of RB proceeds by pseudo-first-order reaction kinetics …
Template-Free Synthesis Of Zsm-5 Type Zeolite Layers On Porous Alumina Disks, Hali̇l Kalipçilar, Ali̇ Çulfaz
Template-Free Synthesis Of Zsm-5 Type Zeolite Layers On Porous Alumina Disks, Hali̇l Kalipçilar, Ali̇ Çulfaz
Turkish Journal of Chemistry
ZSM-5 crystals were synthesized from template-free batches on macroporous \alpha-alumina disks. The SiO_2/Al_2O_3 ratio of the synthesis gel influenced the crystal morphology, surface coverage and intergrowth among the crystals. Prismatic ZSM-5 crystals covered the disk surface when the SiO_2/Al_2O_3 ratio of the batch was higher than 100, whereas spherical polycrystalline particles of ZSM-5 were obtained from batches with a SiO_2/Al_2O_3 ratio of 80. Mordenite type zeolite was formed on the disk surface due to the incorporation of alumina dissolved from the disk when the time of crystallization was extended. The effects of silica source and seeding of the support surface …
A New Approach To Furan-Containing Macrolactones, Christoph Schmidt, Ruth Messmer, Franz Bracher, Jurgen Krauss
A New Approach To Furan-Containing Macrolactones, Christoph Schmidt, Ruth Messmer, Franz Bracher, Jurgen Krauss
Turkish Journal of Chemistry
Furan and tetrahydrofuran heterocycles are part of many natural products, like the Galerucella pheromone, furano epothilones, bipinnatin, and amphidinolides. This paper describes a short and efficient synthetic approach to furan-containing macrolactones in 4 steps, including as key steps a Sonogashira reaction and an olefin metathesis. The resulting compounds were tested at the National Cancer Institute for their cytotoxicity, but did not exhibit significant cytotoxicity in the human tumour cell line screen.
Studies On The Anion Recognition Properties Of Synthesized Receptors Iii: A Novel Thiourea-Based Receptor Constructed By Benzo-15-Crown-5 For Sensing Anions In A Strong Polar Solvent, You-Ming Zhang, Hai-Xian Ren, Yan-Qing Zhou, Rong Luo, Wei-Xia Xu, Tai-Bao Wei
Studies On The Anion Recognition Properties Of Synthesized Receptors Iii: A Novel Thiourea-Based Receptor Constructed By Benzo-15-Crown-5 For Sensing Anions In A Strong Polar Solvent, You-Ming Zhang, Hai-Xian Ren, Yan-Qing Zhou, Rong Luo, Wei-Xia Xu, Tai-Bao Wei
Turkish Journal of Chemistry
A new series of receptors were designed and synthesized, and their interactions with anions, such as F^-, Cl^-, Br^-, I^-, CH_3COO^-, HSO_4^-, and NO_3^-, in DMSO solvent were investigated using UV-Vis absorption spectroscopy. The results showed that hydrogen-bonding complexes were formed between the receptors and the tested anions, such as CH_3COO^- and F^-. It was also found that the selectivity of the receptors for anions could be efficiently tuned by changing the place of the substituent group at the N-phenyl moiety. The recognition mechanism and binding mode are discussed. These findings were expected to be of significance for designing and …
Pvc-Membrane Electrodes Based On 18-Crown-6 And Dibenzo-18-Crown-6 Ethers For Determination Of Silver, Mohsen Mousa Zareh, Magda A. Akl, Ahmd Khlil Gohneim, Mohmed Hussin Abd El-Aziz
Pvc-Membrane Electrodes Based On 18-Crown-6 And Dibenzo-18-Crown-6 Ethers For Determination Of Silver, Mohsen Mousa Zareh, Magda A. Akl, Ahmd Khlil Gohneim, Mohmed Hussin Abd El-Aziz
Turkish Journal of Chemistry
PVC-membrane electrodes for Ag^+ based on either 18-crown-6 (I) or di-benzo-18-crown-6 ether (II) were applied for the first time. The effect of solvent mediator on the electrode performance was discussed. Nernstian slope values were 59 and 58.9 mV/decade for both I and II electrode types, respectively. The linear concentration range was 10^{-5}-10^{-1}M. The detection limit was 7.9 \times 10^{-6} M. The working pH ranges were 5-9 or 4-9, depending on the concentration of Ag^+ ion. The electrodes showed good selectivity towards most of the common alkali, alkaline earths, and transition metal cations. The electrodes were applied successfully for the determination …
A Novel Degradable Adsorbent Of The Hyperbranched Aliphatic Polyester Grafted Cellulose For Heavy Metal Ions, Peng Liu
Turkish Journal of Chemistry
A novel degradable adsorbent for the removal of heavy metal ions from waste water, a hyperbranched aliphatic polyester grafted cellulose (HAPE-Cell), was successfully prepared by the simple one-pot method for the first time. The hyperbranched aliphatic polyester was grafted from the surface hydroxyl groups of natural cotton fibers via the solution polycondensation of the AB_2 monomer, 2, 2-bis(hydroxymethyl)propionic acid (bis-MPA), with the catalysis of p-toluenesulfonic acid (p-TSA). The HAPE-Cell was characterized by elemental analysis, Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM). The adsorption properties of the HAPE-Cell towards the heavy metal ions (Cu(II), Hg(II), …
Activation Of Light Alkanes On Pure And Fe And Al Doped Silica Clusters: A Density Functional And Oniom Study, Mehmet Ferdi̇ Fellah, Işik Önal
Activation Of Light Alkanes On Pure And Fe And Al Doped Silica Clusters: A Density Functional And Oniom Study, Mehmet Ferdi̇ Fellah, Işik Önal
Turkish Journal of Chemistry
C-H bond activation was studied by use of density functional theory (DFT) and ONIOM calculations as implemented in Gaussian 2003 at the B3LYP level utilising 6-31G* as the basis set for Si, Al, and Fe atoms and 3-21G** as the basis set for O and H atoms. Relative energy profiles were determined for pure silica modeled by a Si_7O_{21} cluster and Fe and Al doped silica clusters via coordinate driving calculations. The activation barriers for C-H bond activation of methane and ethane decrease with the substitution of Fe on the silica surface, which theoretically demonstrates a favorable effect of Fe …
A Mechanistic Approach To Elucidate Ethanol Electro-Oxidation, Ni̇yazi̇ Alper Tapan
A Mechanistic Approach To Elucidate Ethanol Electro-Oxidation, Ni̇yazi̇ Alper Tapan
Turkish Journal of Chemistry
In order to elucidate the mechanism of ethanol oxidation, a simple cylindrical diffusion-surface reaction was developed on a platinum disk electrode. An ethanol electro-oxidation mechanism was proposed, in which electrochemical reactions proceed without adsorption of any electro-oxidation products (C2 type) on the surface. After the simulation of the proposed mechanism, it was seen that the model can explain ethanol electro-oxidation behavior without any surface CO formation. The simulation of the mechanism indicated that the formation of acetaldehyde through the oxidation of bulk ethanol is the rate determining step between 0.6 and 0.75 V vs. RHE. After 0.75 V vs. RHE, …
Low Temperature Co Oxidation Kinetics Over Activated Carbon Supported Pt-Sno_X Catalysts, Fatma Soyal Baltacioğlu, Berri̇n Gülyüz, Ahmet Erhan Aksoylu, Zeynep İlsen Önsan
Low Temperature Co Oxidation Kinetics Over Activated Carbon Supported Pt-Sno_X Catalysts, Fatma Soyal Baltacioğlu, Berri̇n Gülyüz, Ahmet Erhan Aksoylu, Zeynep İlsen Önsan
Turkish Journal of Chemistry
The kinetics of low temperature CO oxidation were studied over sequentially impregnated 1wt%Pt-0.25wt%SnO_x supported on HNO_3-oxidized activated carbon (AC3) using a wide range of CO (1-10 mol%) and O_2 (1-4 mol%) concentrations. Intrinsic kinetic data were obtained in the initial rates region at 383 K in the absence and presence of 5-45 mol% H_2 in the feed. A power-function rate expression with positive dependence on CO (0.96) and negative dependence on oxygen (--0.31) was obtained for the low temperature oxidation of CO. The effect of H_2 on CO oxidation rates was also investigated under similar conditions.
Characterization And Co Oxidation Activity Studies Of Co-Based Catalysts, Fi̇li̇z Balikçi, Çi̇ğdem Güldür
Characterization And Co Oxidation Activity Studies Of Co-Based Catalysts, Fi̇li̇z Balikçi, Çi̇ğdem Güldür
Turkish Journal of Chemistry
Cobalt oxide based catalysts were developed for carbon monoxide oxidation at low temperature. The catalysts were prepared by co-precipitation and calcined at 200 °C. Several techniques were used to characterize the catalysts, such as X-ray diffractometer system, N_2 physisorption measurements, scanning electron microscope (SEM), and X-ray photoelectron spectroscopy. Carbon monoxide oxidation studies were carried out to investigate the relation between the characteristic properties of the catalysts and the catalytic activity. Catalytic activity measurements were studied from room temperature to 200 °C, using a feed composition of 1% CO, 21% O_2, and remaining He. X-ray studies showed that the catalysts have …
Direct Hydrothermal Synthesis Of Palladium-Incorporated Silicate-Structured Mesoporous Catalysts, Canan Şener, Ti̇mur Doğu, Gülşen Doğu
Direct Hydrothermal Synthesis Of Palladium-Incorporated Silicate-Structured Mesoporous Catalysts, Canan Şener, Ti̇mur Doğu, Gülşen Doğu
Turkish Journal of Chemistry
Pd-Si-structured novel mesoporous nanocomposite catalytic materials, having quite high Pd/Si ratios, were synthesized by an acidic direct hydrothermal synthesis route. The nanocomposite catalytic materials were then characterized by XRD, XPS, EDS, nitrogen adsorption, and SEM techniques. Unlike MCM-41, the XRD patterns indicated a rather wide d_{(100)} band at a 2\theta value of about 1.9. The materials, with very high Pd/Si wt ratios between 1.43 and 2.66, were synthesized and had BJH surface area values between 600 and 200 m^2/g. The pore size distributions of these materials were also quite narrow, indicating pores between 2 and 7 nm.
Direct Formation Of H_2o_2 From H_2 And O_2, Meltem Yildiz, Ayşe Ni̇lgün Akin
Direct Formation Of H_2o_2 From H_2 And O_2, Meltem Yildiz, Ayşe Ni̇lgün Akin
Turkish Journal of Chemistry
The direct combination of hydrogen and oxygen to form hydrogen peroxide in liquid media with prepared catalysts was carried out in a slurry reactor at atmospheric pressure and room temperature. An O_2/H_2 ratio of 2:1 with a 50 mL/min flow rate was used in these experiments. Catalyst activity measurements were tested by the iodometric titration method using KMnO_4. The results are discussed based on the effects of support material, catalyst preparation method, reaction time, and medium (type of halide and acid) on hydrogen peroxide yield in direct oxidation of hydrogen to produce hydrogen peroxide. Our results showed that the catalytic …
Kinetics Of Synthesis Of Isobutyl Propionate Over Amberlyst-15, Ali̇me İzci̇, Hali̇t Levent Hoşgün
Kinetics Of Synthesis Of Isobutyl Propionate Over Amberlyst-15, Ali̇me İzci̇, Hali̇t Levent Hoşgün
Turkish Journal of Chemistry
The esterification of propionic acid with isobutanol in the presence of Amberlyst-15 as a catalyst was studied. Isobutyl propionate synthesized in this reaction has the fragrance of rum and is used in the food industry. The experiments were carried out in a stirred batch reactor at temperatures from 318 K to 348 K. As a solvent, 1,4 dioxan was used. The effects of the amount of catalyst used, the reaction time, the stirring speed, and the reaction temperature on the synthesis of isobutyl propionate were investigated. It was observed that solid-liquid external mass transfer resistance resulting from various stirring speeds …
Preparation And Morphological Characterization Of A Catalytic Soot Oxidation Sic Foam Filter, Başar Çağlar, Deni̇z Üner
Preparation And Morphological Characterization Of A Catalytic Soot Oxidation Sic Foam Filter, Başar Çağlar, Deni̇z Üner
Turkish Journal of Chemistry
The coating characteristics of Pb-Co mixed metal oxide soot oxidation catalysts over a SiC foam filter were studied. The coating was done via incipient wetness impregnation of a slurry with Pb/Co weight ratio = 2. The coating was accomplished by 3 consecutive impregnation-drying-calcination cycles. After each cycle surface structure and composition were monitored by scanning electron microscope (SEM). SEM analysis revealed that the surface composition of Pb was high on the high porosity region and surface composition of Co was high on the low porosity region inside the filter. These overlayers were tested for their soot oxidation ability by depositing …
Preparation And Characterization Of Ordered Tio_2 Photocatalysts: Films And Mesoporous Structures, Orçun Ergün, Osman Karslioğlu, Ayşen Yilmaz, Deni̇z Üner
Preparation And Characterization Of Ordered Tio_2 Photocatalysts: Films And Mesoporous Structures, Orçun Ergün, Osman Karslioğlu, Ayşen Yilmaz, Deni̇z Üner
Turkish Journal of Chemistry
Two different ordered TiO_2 structures were prepared as sol-gel films coated on glass and as mesoporous structures in order to study the effect, in 2-D or in 3-D, of bulk size on photocatalytic activity. Multilayer TiO_2 films were coated on glass by the sol-gel dip coating method. The UV-VIS characteristics of the films, with respect to the number of coating layers, were monitored. UV-VIS measurements implied an ordered TiO_2 structure grown on ITO glass. The second approach involved loading TiO_2 in mesoporous SBA-15 powder. Ti-SBA-15 with Ti/Si (mole/mole) ratios between 0.05 and 0.30 were prepared and characterized by XRD and …
Investigation Of Biodiesel Production From Canola Oil Using Mg-Al Hydrotalcite Catalysts, Oğuzhan İlgen, İsmai̇l Di̇nçer, Meltem Yildiz, Ertan Alpteki̇n, Nezahat Boz, Mustafa Çanakçi, Ayşe Ni̇lgün Akin
Investigation Of Biodiesel Production From Canola Oil Using Mg-Al Hydrotalcite Catalysts, Oğuzhan İlgen, İsmai̇l Di̇nçer, Meltem Yildiz, Ertan Alpteki̇n, Nezahat Boz, Mustafa Çanakçi, Ayşe Ni̇lgün Akin
Turkish Journal of Chemistry
Biodiesel produced by the transesterification of vegetable oils is a promising alternative fuel to diesel because of limited fossil fuel resources and environmental concerns. The use of heterogeneous catalysts greatly simplifies the technological process by facilitating the separation of the post-reaction mixture. The purpose of the present work was to examine a heterogeneous catalyst, in particular, Mg-Al hydrotalcites, to produce methyl esters of canola oil. In this study, the transesterification of canola oil with methanol was studied in a heterogeneous system, using Mg-Al hydrotalcites as solid base catalysts. The results showed that methanol is the best alcohol for this reaction …
Deactivation Of A Co-Precipitated Co/Al_2o_3 Catalyst, Meltem Yildiz, Ayşe Ni̇lgün Akin
Deactivation Of A Co-Precipitated Co/Al_2o_3 Catalyst, Meltem Yildiz, Ayşe Ni̇lgün Akin
Turkish Journal of Chemistry
The effects of reaction temperature, feed ratio, space time, and CO percentage in feed on the deactivation conditions of a co-precipitated 36 wt% Co/Al_2O_3 catalyst in CO hydrogenation were investigated. Environmental-SEM-EDX and temperature-programmed reduction (TPR) studies were performed on used catalysts to investigate the effect of reaction conditions on catalyst deactivation. Intensive coke deposition on the catalyst was observed at a reaction temperature of about 573 K. Increasing the H_2/CO ratio also increased the catalyst activity. Methane formed as the main product at high H_2/CO ratios. Although catalyst activity did not change significantly during the 9-h reaction period at all …
Catalytic Processes For Clean Hydrogen Production From Hydrocarbons, Zeynep İlsen Önsan
Catalytic Processes For Clean Hydrogen Production From Hydrocarbons, Zeynep İlsen Önsan
Turkish Journal of Chemistry
Conversion of hydrocarbon fuels to hydrogen with a high degree of purity acceptable for fuel cell operation presents interesting challenges for the design of new selective catalysts and catalytic processes. Natural gas, LPG, gasoline, and diesel are regarded as promising hydrocarbon fuels. Methanol has received attention despite its toxicity, and ethanol has recently become of interest as a much less toxic and renewable resource. Selective catalytic processes considered for commercial use are based on steam reforming and partial oxidation of these fuels. Autothermal reforming (ATR) or indirect partial oxidation (IPOX) combines total oxidation (TOX), steam reforming (SR), and water-gas shift …
Alcohols As Alternatives To Petroleum For Environmentally Clean Fuels And Petrochemicals, Ti̇mur Doğu, Di̇lek Varişli
Alcohols As Alternatives To Petroleum For Environmentally Clean Fuels And Petrochemicals, Ti̇mur Doğu, Di̇lek Varişli
Turkish Journal of Chemistry
In this review article, some of the challenging research areas related to the development of novel catalysts and catalytic processes for the chemical fixation of CO_2 by converting it to alcohols and ethers, and for the conversion of alcohols to olefins and other hydrocarbons are reviewed. Ethanol, methanol, and the ethers derived from them, such as DEE and DME, have good burning characteristics and may be considered attractive transportation fuel alternates. New processes for catalytic selective oxidation and dehydration of alcohols may open up new pathways for the production of olefins and other petrochemicals from non-petroleum feedstock. Developments in CO_2 …