scholarly journals Effect of a modified 13X zeolite support in Pd-based catalysts for hydrogen oxidation at room temperature

RSC Advances ◽  
2021 ◽  
Vol 11 (60) ◽  
pp. 38047-38053
Author(s):  
Younghee Jang ◽  
Sang Moon Lee ◽  
Sung Su Kim
Keyword(s):  
Room Temperature ◽  
Zeolite Catalyst ◽  
Hydrogen Oxidation ◽  
13X Zeolite ◽  
Zeolite Support ◽  
Oxidation Of Hydrogen

This study investigated the effect of a modified 13X zeolite to Pd/zeolite catalyst on the oxidation of hydrogen to ensure safety from hydrogen leakage.

Catalothermionic Power Generator Based on Internal Electron Emission in Ni/SiC Heterojunction Nanostructures

2009 ◽  
Author(s):  
Eduard G. Karpov ◽  
Ievgen I. Nedrygailov
Keyword(s):  
Energy Transfer ◽  
Electron Emission ◽  
Oxidation Reaction ◽  
Hydrogen Oxidation ◽  
Schottky Barriers ◽  
Gas Mixture ◽  
Hydrogen Oxidation Reaction ◽  
Power Generator ◽  
Oxidation Of Hydrogen ◽  
Internal Electron

We report on the unusual properties of single-faced SiC metal-semiconductor heterojunction nanostructures manifested by the ability to atalyze the hydrogen oxidation reaction, and also maintain internal electron emission over the Schottky barriers. As a result a stationary current has been detected in the preheated nanostructure when exposed to the oxyhydrogen gas mixture flux. The structures maintain both the non-adiabatic and electron-phonon channels of energy transfer, and the results of studies indicate the possibility for a very efficient conversion of chemical energy released in the catalytic oxidation of hydrogen into electricity.

scholarly journals Ionophore-Assisted Electrochemistry of Neutral Molecules: Oxidation of Hydrogen in an Ionic Liquid Electrolyte

2019 ◽  
Author(s):  
Johannes Wandt ◽  
Junqiao Lee ◽  
Damien Arrigan ◽  
Debbie Silvester
Keyword(s):  
Ionic Liquid ◽  
Room Temperature ◽  
Electrochemical Sensors ◽  
Liquid Electrolyte ◽  
Ion Binding ◽  
Ionic Liquid Electrolyte ◽  
Neutral Gas ◽  
Oxidation Of Hydrogen ◽  
Gas Molecules ◽  
Novel Concept

<p>The electrochemical properties of gas molecules are of great interest for both fundamental and applied research. In this study, we introduce a novel concept to systematically alter the electrochemical behavior and, in particular, the redox potential of neutral gas molecules. The concept is based on the use of an ion-binding agent, or ‘ionophore’, to bind and stabilize the ionic electrochemical reaction product. We demonstrate that the ionophore-assisted electrochemical oxidation of hydrogen in a room temperature ionic liquid electrolyte is shifted by almost 1 V towards more negative potentials in comparison to an ionophore-free electrolyte. The altered electrochemical response in the presence of the ionophore not only yields insights into the reaction mechanism but can be used also to determine the diffusion coefficient of the ionophore species. This ionophore-modulated electrochemistry of neutral gas molecules opens up new avenues for the development of highly selective electrochemical sensors.</p>

scholarly journals The role of Praseodymium oxide-Impregnated Clinoptilolite Zeolite Catalyst to Increase Octane Number in Gasoline

2018 ◽  
Vol 67 ◽  
pp. 03051
Author(s):  
Eny Kusrini ◽  
Yan Mulders Togar ◽  
Vino Hasyim ◽  
Anwar Usman
Keyword(s):  
Octane Number ◽  
Room Temperature ◽  
Zeolite Catalyst ◽  
Nitrate Hexahydrate ◽  
Impregnation Method ◽  
Praseodymium Oxide ◽  
Organic Impurities ◽  
Activity Performance ◽  
Clinoptilolite Zeolite

In the present work, the role of praseodymium oxide as a promotor of active site in zeolite base as catalyst for increasing the octance number in gasoline were investigated. In this study, we used three types of catalyst, namely the activated clipnotilolite zeolite (catalyst 1), Pr6O11-impregnated clinoptilolite zeolite 0.01 (w/w%) (catalyst 2) and Pr6O11-impregnated clinoptilolite zeolite 0.1 (w/w%) (catalyst 3). Both catalyst 2 and 3 were prepared by impregnation method. The calcination temperature for all of catalysts was set at 500°C for 2 hours to remove the organic impurities and stabilize the structure of catalyst. The Si/Al ratio increased from 5.1 to 5.85 with prasedymium nitrate hexahydrate percentage in catalysts 2 and 3 were 0.14 and 0.05%, respectively. The surface area of catalysts 1 - 3 are 19.42, 18.09 and 15.22 m2/g, respectively. The activity performance of catalyst 3 with 1 and 3 % loading at 27.7°C for 2 min have increased the octane number of 0.1. Increasing octane number of 0.1 was also confirmed by GC-MS data which showed the presence of decreasing C4-C11 hydrocarbon compounds and increasing of aromatic compounds. Pr6O11-impregnated clinoptilolite zeolite catalyst is potential for application in fuel system to increase octane number at room temperature (27.7°C).

scholarly journals Catalytic activity of Pd-Ni in the oxidation of hydrogen for the safety of nuclear power plant

2016 ◽  
Vol 18 (1) ◽  
pp. 15-18
Author(s):  
Dariusz Łomot ◽  
Zbigniew Karpiński
Keyword(s):  
Bimetallic Catalysts ◽  
Nuclear Power ◽  
Power Plants ◽  
Hydrogen Oxidation ◽  
Precious Metals ◽  
Oxidation Of Hydrogen ◽  
Different Temperatures ◽  
Flowing System ◽  
Over Time ◽  
Excellent Stability

Abstract Pd-Ni/Al2O3 systems were investigated in the reaction of hydrogen oxidation in terms of their possible application as catalysts used in passive autocatalytic recombiners (PARs) used in nuclear power plants. Testing experiments were carried out in a flowing system at different temperatures and humidity of the reaction mixture. The bimetallic catalysts exhibited higher response to the increase of temperature and higher resistance to inhibit water than the monometallic palladium catalyst. They showed excellent stability during a few tens of hours, similarly, like their monometallic counterpart. Our bimetallic catalysts of hydrogen oxidation can be used as cheaper alternatives to catalysts based on the precious metals in the hydrogen oxidation without loss of their activity over time.

Room-Temperature Reactor Packed with Hydrophobic Catalysts for the Oxidation of Hydrogen Isotopes Released in a Nuclear Facility

2011 ◽  
Vol 48 (8) ◽  
pp. 1184-1192 ◽  
Author(s):  
Yasunori IWAI ◽  
Katsumi SATO ◽  
Junichi TANIUCHI ◽  
Hiroshi NOGUCHI ◽  
Hitoshi KUBO ◽  
...  
Keyword(s):  
Room Temperature ◽  
Hydrogen Isotopes ◽  
Nuclear Facility ◽  
Oxidation Of Hydrogen

scholarly journals Ionophore-Assisted Electrochemistry of Neutral Molecules: Oxidation of Hydrogen in an Ionic Liquid Electrolyte

2019 ◽  
Author(s):  
Debbie Silvester ◽  
Johannes Wandt ◽  
Junqiao Lee ◽  
Damien Arrigan
Keyword(s):  
Ionic Liquid ◽  
Room Temperature ◽  
Applied Research ◽  
Electrochemical Sensors ◽  
Liquid Electrolyte ◽  
Ionic Liquid Electrolyte ◽  
Neutral Gas ◽  
Oxidation Of Hydrogen ◽  
Gas Molecules ◽  
Novel Concept

The electrochemical properties of gas molecules are of high interest for both fundamental and applied research. In this study, we introduce a novel concept to systematically alter the electrochemical behavior and, in particular, the redox potential of neutral gas molecules. The concept is based on the use of an ionophore to bind and stabilize the ionic electrochemical reaction product. We demonstrate that the ionophore-assisted electrochemical oxidation of hydrogen in a room temperature ionic liquid electrolyte is shifted by almost 1 V towards more negative potentials in comparison to an ionophore-free electrolyte. The altered electrochemical response in the presence of the ionophore yields insights into the reaction mechanism and can be used to determine the diffusion coefficient of the ionophore species. The ionophore-modulated electrochemistry of neutral gas molecules opens new avenues for the development of selective electrochemical sensors with reduced cross-sensitivity.

Catalytic Oxidation of Toluene with Ozone Over the Ru-Mn/Desilicated Nanoporous H-Zeolite Socony Mobil-5 at Room Temperature

2021 ◽  
Vol 21 (7) ◽  
pp. 3868-3871
Author(s):  
Jihee Kim ◽  
Jung Eun Lee ◽  
Abid Farooq ◽  
Sang Chai Kim ◽  
Sang-Chul Jung ◽  
...  
Keyword(s):  
Pore Size ◽  
Catalytic Oxidation ◽  
Surface Area ◽  
Removal Efficiency ◽  
Pore Volume ◽  
Bimetallic Catalysts ◽  
Room Temperature ◽  
Average Pore Size ◽  
Average Pore ◽  
Zeolite Support

In this study, the effect of Ru-Mn bimetallic catalysts in combination with a zeolite support on the removal of toluene in the presence of ozone at room temperature was investigated. Desili-cated HZSM-5 (DZSM) was fabricated and applied as a Ru-Mn support for the removal of toluene (100 ppm) in the presence of ozone (1000 ppm) at room temperature. The surface area, pore volume, and average pore size of Ru-Mn with a DZSM support (RuMn/DZSM) were measured and compared with those of Ru-Mn/HZSM-5 (RuMn/HZSM). The pore size of RuMn/DZSM (69 Å) was much larger than that of RuMn/HZSM-5 (5.5 Å). In addition, the pore volumes of RuMn/DZSM and RuMn/HZSM were 0.64 and 0.25 cm3/g, respectively. Furthermore, the ratios of Mn3+/Mn4+ and Ovacancy/Olattice of RuMn/DZSM were larger than those of RuMn/HZSM-5. The removal efficiency of toluene of RuMn/DZSM was higher than that of RuMn/HZSM due to its larger pore volume, pore size, and the increased ratios of Mn3+/Mn4+ and Ovacancy/Olattice.

Isothermal interpretations of oscillatory ignition during hydrogen oxidation in an open system. I. Analytical predictions and experimental measurements of periodicity

1986 ◽  
Vol 405 (1828) ◽  
pp. 117-128 ◽  
Keyword(s):  
Flow System ◽  
Hydrogen Oxidation ◽  
Mass Conservation ◽  
Stationary States ◽  
Third Body ◽  
Chain Reactions ◽  
Sequence Of Events ◽  
Oxidation Of Hydrogen ◽  
Branched Chain ◽  
Supercritical Reaction

The oxidation of hydrogen under well stirred, flowing conditions is the natural prototype of branched-chain reactions in open, gaseous systems. Experimentally, it exhibits the classical forms for the ( p - T a ) first and second ignition limits in the flow system. The constant reactant supply ensures that stationary states exist at subcritical conditions whereas the supercritical reaction is a repetitive, oscillatory sequence of events. In a linked pair of papers, we investigate isothermal criticality at the second limit in terms of changing nature of the singularities for the mass conservation equations and derive kinetic relationships that explain the oscillatory features. In this paper the origins of oscillatory ignition are traced analytically to chain-branching via H atoms coupled to the changing third-body efficiency in the elementary process H + O 2 + M → HO 2 + M, when water formed during ignition is displaced by the inflow of fresh hydrogen and oxygen. Analytical predictions are made of the periods between successive ignitions and of the conditions at which oscillatory reaction is transformed to a stationary state. A composition limit for the existence of oscillatory ignition in the (lean) mixture H 2 + 15O 2 + 14N 2 is located experimentally and explained in terms of the analytical inter­pretations presented here.

Scope of Metal Loaded Microporous Zeolite-Y as Catalyst in Ozone Initiated Oxidation of n-hexadecane

2009 ◽  
Vol 12 (2) ◽  
Author(s):  
V. S. R. Rajasekhar Pullabhotla ◽  
S. B. Jonnalagadda
Keyword(s):  
Metal Ion ◽  
Zeolite Catalyst ◽  
Catalyst Surface ◽  
Zeolite Y ◽  
Y Zeolite ◽  
Substrate Molecule ◽  
Zeolite Support ◽  
Active Intermediate ◽  
Plausible Mechanism ◽  
Microporous Zeolite

AbstractThe efficiency of metal loaded microporous materials, zeolite-Y as catalysts in the ozone initiated oxy-functionalisation of long chained n-alkanes is investigated at moderate temperature (20 ± 1 °C) and pressure conditions (1 atm.). The efficiencies of 0.5% Pd, Ni, V and U loaded microporous zeolite-Y catalysts on ozonation of higher alkanes (n-hexadecane), with respect to the conversion and transformation towards keto products are compared. In the catalysed ozonation, n-hexadecane is converted to 4-, 3- and 2- keto isomers as major products with varied selectivity and % conversions. A plausible mechanism assuming the chemisorption of the substrate molecule on the catalyst surface and further electron transfer between the metal ion loaded on the zeolite support and the active intermediate formed in course of reaction for the ozone initiated oxidation of n-hexadecane with heterogeneous Ni loaded Na-Y zeolite catalyst is proposed.

scholarly journals The Reaction of Aza Michael Catalyzed by Zeolite Cu-ZSM-5 under Solvent-Free Conditions

2018 ◽  
pp. 1-7
Author(s):  
Elmeliani M’hammed ◽  
Djafri Fatiha ◽  
Djafri Ayada
Keyword(s):  
Organic Chemistry ◽  
Room Temperature ◽  
Zeolite Catalyst ◽  
Catalytic Efficiency ◽  
Solvent Free ◽  
High Yield ◽  
Chiral Auxiliaries ◽  
Amino Esters ◽  
New Synthesis ◽  
Solvent Free Conditions

The study is carried out to test the catalytic efficiency of Cu-ZSM-5 zeolite catalyst on the reaction of Aza Michael under solvent-free conditions, at room temperature this reaction is most exploited in organic chemistry, b-amino -esters, ketones, nitriles are useful for the preparation of several natural bioactive products, antibiotics, and chiral auxiliaries, through the use of the porous material catalyst (zeolite Cu-ZSM-5), and the reaction of Aza Michael addition a series of amines on α, β-unsaturated methyl acrylate, we have synthesized new cc or c-heteroatom products, these compounds is an attractive area of researchers in synthetic organic chemistry, and we have developed new synthesis methodologies for the preparation of these products. The reaction was carried out with favourable conditions: ambient temperature, and without solvent, that the products, which are synthesized, gave us a high yield, and excellent chemoselectivity.

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