Competitive sorption kinetics of oxygen and carbon monoxide on platinum*1

1970 ◽  
Vol 18 (1) ◽  
pp. 70-76 ◽  
Author(s):  
B WOOD
Keyword(s):  
Carbon Monoxide ◽  
Sorption Kinetics ◽  
Competitive Sorption ◽  
Kinetics Of

Modeling of sorption kinetics of U(VI) micro-quantities nanostructured materials with anatase mesoporous structures

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Veniamin Zheleznov ◽  
Aleksey Golikov ◽  
Tatiana Sokolnitskaya ◽  
Sergey Ivannikov
Keyword(s):  
Nanostructured Materials ◽  
Sorption Kinetics ◽  
Uranyl Ion ◽  
Competitive Sorption ◽  
Hydroxyl Groups ◽  
Complex Ions ◽  
The Stability ◽  
Kinetics Of ◽  
Mesoporous Structures ◽  
Ionic Forms

Abstract The sorption kinetics of uranyl ions micro-quantities from fluoride solutions by nanostructured materials with anatase mesoporous structures has been studied. Using the model of competitive sorption of ions and positively charged complexes of uranyl ion on deprotonated hydroxyl groups of an anatase, kinetic curves of changes in the ratio of ionic forms of uranium in solution were calculated. Modeling was carried out under the assumption of a two-stage mechanism of uranium complex ions sorption. The modeling considered the influence of the uranyl ion carbonate complexes formation. The shift in equilibrium among ionic forms of uranyl correlates with the stability of the complexes in solution.

SELECTIVE DETERMINATION OF CARBON MONOXIDE BY SINGLE METAL OXIDE SENSOR

2019 ◽  
Vol 62 (4) ◽  
pp. 76-81
Author(s):  
Kristina L. Chegereva ◽  
Alexey V. Shaposhnik ◽  
Alexey A. Zvyagin ◽  
Pavel V. Moskalev
Keyword(s):  
Carbon Monoxide ◽  
Qualitative Analysis ◽  
Chemical Interaction ◽  
Ethanol Vapor ◽  
Sorption Kinetics ◽  
Temperature Modulation ◽  
Selective Determination ◽  
Chemisorbed Oxygen ◽  
Kinetics Of

Semiconductor sensors are often used to solve an important practical problem – the determination of the concentration of carbon monoxide in the air. Their disadvantage is the low selectivity, which can lead to false alarm when other reducing gases such as ammonia or ethanol vapor appear in the air. To increase the selectivity, we used pulsed temperature modulation in combination with a special composition of the gas sensitive layer of the sensor. The use of pulse temperature modulation has revealed the features of the analyte associated with the sorption kinetics at the surface of the sensor, with the kinetics of the chemical interaction between reductant analytes and chemisorbed oxygen, and the kinetics of desorption of chemical interaction products. However, information on the qualitative composition of the medium is contained in the experimental data in an implicit form, because the qualitative analysis procedure with the use of low selectivity sensors has so far remained undeveloped. In this paper, we proposed a qualitative analysis method based on the power-law regression model that relates the concentration of analyte gas to the electrical resistance of the sensor at various times during the measurement cycle. The experimental procedure shown in our work leads to an increase in the sensitivity of the quantitative analysis by one or two orders of magnitude depending on the concentration of carbon monoxide.

Competitive Sorption Kinetics of Inhibited Endo- and Exoglucanases on a Model Cellulose Substrate

Langmuir ◽  
2012 ◽  
Vol 28 (41) ◽  
pp. 14598-14608 ◽  
Author(s):  
Samuel A. Maurer ◽  
Claire N. Bedbrook ◽  
Clayton J. Radke
Keyword(s):  
Sorption Kinetics ◽  
Competitive Sorption ◽  
Cellulose Substrate ◽  
Kinetics Of

Study of nickel-molybdenum catalysts for methanation of carbon monoxide

1980 ◽  
Vol 45 (3) ◽  
pp. 783-790 ◽  
Author(s):  
Petr Taras ◽  
Milan Pospíšil
Keyword(s):  
Carbon Monoxide ◽  
Catalytic Activity ◽  
Mixed Oxides ◽  
Minor Component ◽  
Fast Neutrons ◽  
Scanning Calorimetry ◽  
Low Concentrations ◽  
Γ Rays ◽  
Molybdenum Catalysts ◽  
Kinetics Of

Catalytic activity of nickel-molybdenum catalysts for methanation of carbon monoxide and hydrogen was studied by means of differential scanning calorimetry. The activity of NiMoOx systems exceeds that of carrier-free nickel if x < 2, and is conditioned by the oxidation degree of molybdenum, changing in dependence on the composition in the region Mo-MoO2. The activity of the catalysts is adversely affected by irradiation by fast neutrons, dose 28.1 Gy, or by γ rays using doses in the region 0.8-52 kGy. The system is most susceptible to irradiation in the region of low concentrations of the minor component (about 1 mol.%). The dependence of changes in catalytic activity of γ-irradiated samples on the dose exhibits a maximum in the range of 2-5 kGy. The changes in catalytic activity are stimulated by the change of reactivity of the starting mixed oxides, leading to different kinetics of their reduction and modification of their adsorption properties. The irradiation of the catalysts results in lowered concentration of the active centres for the methanation reaction.

Kinetics of catalytic reduction of nitrogen oxide by carbon monoxide on CuO/Al2O3 catalyst

1983 ◽  
Vol 48 (11) ◽  
pp. 3202-3208 ◽  
Author(s):  
Zdeněk Musil ◽  
Vladimír Pour
Keyword(s):  
Carbon Monoxide ◽  
Nitrogen Oxide ◽  
Rate Equation ◽  
Catalytic Reduction ◽  
Zero Order ◽  
Spectroscopic Measurements ◽  
First Order ◽  
Ir Spectroscopic ◽  
Kinetics Of ◽  
Al2o3 Catalyst

The kinetics of the reduction of nitrogen oxide by carbon monoxide on CuO/Al2O3 catalyst (8.36 mass % CuO) were determined at temperatures between 413 and 473 K. The reaction was found to be first order in NO and zero order in CO. The observed kinetics are consistent with a rate equation derived from a mechanism proposed on the basis of IR spectroscopic measurements.

Kinetics of carbon monoxide methanation on a Ni/SiO2 catalyst

1990 ◽  
Vol 55 (7) ◽  
pp. 1678-1685
Author(s):  
Vladimír Stuchlý ◽  
Karel Klusáček
Keyword(s):  
Carbon Monoxide ◽  
Reaction Rate ◽  
Catalyst Activity ◽  
Adsorbed Hydrogen ◽  
Reaction Products ◽  
Co Methanation ◽  
Molar Ratios ◽  
Rate Determining Step ◽  
Higher Temperature ◽  
Kinetics Of

Kinetics of CO methanation on a commercial Ni/SiO2 catalyst was evaluated at atmospheric pressure, between 528 and 550 K and for hydrogen to carbon monoxide molar ratios ranging from 3 : 1 to 200 : 1. The effect of reaction products on the reaction rate was also examined. Below 550 K, only methane was selectively formed. Above this temperature, the formation of carbon dioxide was also observed. The experimental data could be described by two modified Langmuir-Hinshelwood kinetic models, based on hydrogenation of surface CO by molecularly or by dissociatively adsorbed hydrogen in the rate-determining step. Water reversibly lowered catalyst activity and its effect was more pronounced at higher temperature.

Kinetics of γ-alumina chlorination by carbon monoxide and chlorine

1982 ◽  
Vol 52 (1-3) ◽  
pp. 211-215 ◽  
Author(s):  
A. Tóth ◽  
I. Bertóti ◽  
T. Székely
Keyword(s):  
Carbon Monoxide ◽  
Kinetics Of

scholarly journals The kinetics of hœmoglobin VI -The competition of carbon monoxide and oxygen for hœmoglobin

1934 ◽  
Vol 115 (795) ◽  
pp. 473-495 ◽  
Keyword(s):  
Carbon Monoxide ◽  
Reverse Reaction ◽  
Experimental Part ◽  
Kinetics Of ◽  
Broad Outline

The experimental part of the research to be described below is given in two main sections. Of these Section 1 deals with the results obtained in measurements of the rate of displacement of oxygen from combination with hœmoglobin by carbon monoxide. Section 2 gives, in corresponding fashion, the results for the reverse reaction, namely, the displacement of carbon monoxide from combination with hœmoglobin by oxygen. The theoretical aspects of theses two reactions have already been dealt with in broad outline at the end of Part IV, with which it will be assumed that the reader is fully acquainted. Some further considerations, however, arise and these are given in Section 3 of the present paper.

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