Effect of the ionizing radiation on the catalytic activity of the BASF K-3-10 catalyst in the low-temperature conversion of carbon monoxide by water vapour. Stability of the radiation catalytic effects

The radiation catalytic properties of the BASF K-3-10 catalyst were studied, namely the dependence of these effects on the time interval between the catalyst irradiation and the reaction itself and also on the length of the catalyst use. The catalytic effects decrease exponentially with the interval between the irradiation and the reaction if the catalyst is kept in the presence of air. The stability of effects induced by various types of radiations increases in the sequence beta radiation - gamma radiation - fast neutrons. The radiation catalytic effect stability in the reaction increases in the same sequence.

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Effect of the ionizing radiation on the catalytic activity of the BASF K-3-10 catalyst in the low-temperature conversion of carbon monoxide by water vapour. Catalytic activity of the pre-irradiated catalyst

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19860279 ◽

1986 ◽

Vol 51 (2) ◽

pp. 279-287 ◽

Cited By ~ 1

Author(s):

Alois Motl

Keyword(s):

Carbon Monoxide ◽

Catalytic Activity ◽

Low Temperature ◽

Ionizing Radiation ◽

Water Vapour ◽

Effective Activation Energy ◽

Absorbed Dose ◽

Beta Radiation ◽

Fast Neutrons ◽

Different Types

The catalytic activity of the BASF K-3-10 catalyst with regard to the low-temperature conversion of carbon monoxide by water vapour and its changes after irradiation of the contact area by gamma or beta radiation or by fast neutrons has been investigated. The irradiated samples exhibit a moderately or even substantially higher catalytic activity in comparison with the non-irradiated catalyst, the change being dependent on the absorbed dose; moreover, the effective activation energy of the reaction increases, too. Important differences in the action of different types of the ionizing radiation used have been observed and their probable explanation is offered. In course of these experiments the catalysts were analyzed and the specific surface of the catalyst was measured at various stages of their history. It has been found that at all stages the specific surfaces of the irradiated catalyst are equal to the respective specific surfaces of the non-irradiated contacts.

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Study of nickel-molybdenum catalysts for methanation of carbon monoxide

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19800783 ◽

1980 ◽

Vol 45 (3) ◽

pp. 783-790 ◽

Cited By ~ 1

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.

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Über den Einfluß äußerer Magnetfelder auf die Aktivität ferromagnetischer Katalysatoren

Zeitschrift für Naturforschung A ◽

10.1515/zna-1953-0904 ◽

1953 ◽

Vol 8 (9) ◽

pp. 538-546 ◽

Cited By ~ 1

Author(s):

E. Justi ◽

G. Vieth

Keyword(s):

Catalytic Activity ◽

Nickel Powder ◽

Catalytic Effect ◽

Theoretical Treatment ◽

High Catalytic Activity ◽

Experimental Proof ◽

Apparent Lack ◽

Low Field ◽

Order Of Magnitude ◽

Catalytic Effects

J.A. Hedvall has discovered “internal” magneto-catalytic effects; the activity of ferromagnetic catalyst changes upon transgressing the Curie-interval. The present publication deals with finding an “external” magneto-catalytic effect consisting of the influence of external magnetic fields upon the activity of ferromagnetic catalysts. This can be shown quite clearly in capillaries of high purity ferromagnetic nickel by experiments applying the o-p-hydrogen conversion. In this reaction the conversion rises so steeply with relatively low field strengths that even the magnetic earth field should enhance the catalytic activity of nickel in compact form; a few hundred oersted may suffice for doubling the conversion and at some 1000 or 10.000 oersted a saturation value of the conversion is reached. The connection between catalytic activity and magnetism finds further support by a corresponding catalytic retentivity.From the theory of ferromagnetism, especially the studies of Néel, it is known that extremely small ferromagnetic particles of the order of magnitude of Blochs walls, i. e. some 10—4 mm, posses high permanent magnetism. This fact appears significant in this connection for the high catalytic activity of finely divided powder catalysts such as Raney catalysts. This permanent magnetism explains also the apparent lack of the external magneto-catalytic effect when using a nickel powder catalyst. The theoretical treatment of the results cannot yet give a definite explanation; before this can be given the experiments must be extended to ordinary chemical reactions. To this end the prerequisits for such experiments are being established.Independently thereof the experimental proof for the external catalytic effect serves to ascertain that the internal Hedvall effects are primarily correlated to the ferromagnetic and paramagnetic states of matter.

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Synergistic Effects of Co3O4-CeO2 Nanoparticles towards Catalytic Oxidation of Aromatic Hydrocarbons: A Study in Association with Carbon Monoxide and Humidity

Journal of Nanomaterials ◽

10.1155/2021/5542281 ◽

2021 ◽

Vol 2021 ◽

pp. 1-9

Author(s):

Trung Dang-Bao ◽

Hong Phuong Phan ◽

Phung Anh Nguyen ◽

Pham Phuong Trang Vo ◽

Van Tien Huynh ◽

...

Keyword(s):

Carbon Monoxide ◽

Catalytic Activity ◽

Catalytic Oxidation ◽

Synergistic Effects ◽

Active Oxygen Species ◽

High Dispersion ◽

High Catalytic Activity ◽

Impregnation Method ◽

Temperature Programmed ◽

The Stability

In this study, a series of Co3O4-CeO2 nanocomposites with various Co3O4 loading were fabricated by the impregnation method using cobalt(II) acetate as the cobalt precursor for the treatment of benzene, toluene, ethylbenzene, and xylene (BTEX). The as-prepared Co3O4-CeO2 nanocomposites were thoroughly characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Brumauer-Emmett-Teller (BET), hydrogen temperature-programmed reduction (H2-TPR), and temperature-programmed desorption (O2-TPD). The excellent reproduction of active oxygen species caused by the high dispersion of Co3O4 crystals on the CeO2 supports was established. In addition, the reduction peaks of Co3O4-CeO2 nanocomposites were found at much lower temperatures compared to pure CeO2, considering their unique redox property influencing on the high catalytic activity. Among the characterized materials, the 5.0 wt.% Co3O4 supported on CeO2 (5.0Co–Ce) was the best system for catalytic oxidation of xylene, along with excellent performances in the cases of benzene, ethylbenzene, and toluene. Its catalytic activity increased in the order: benzene < xylene < ethylbenzene < toluene . Furthermore, the addition of carbon monoxide (CO) as a coreactant permitted to improve the catalytic performances in such oxidations as well as the stability of as-prepared catalysts, even under humid conditions.

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Highly active and stable Au@CuxO core–shell nanoparticles supported on alumina for carbon monoxide oxidation at low temperature

RSC Advances ◽

10.1039/c6ra07358a ◽

2016 ◽

Vol 6 (79) ◽

pp. 75126-75132 ◽

Cited By ~ 1

Author(s):

Weining Zhang ◽

Qingguo Zhao ◽

Xiaohong Wang ◽

Xiaoxia Yan ◽

Sheng Han ◽

...

Keyword(s):

Carbon Monoxide ◽

Catalytic Activity ◽

Low Temperature ◽

Co Oxidation ◽

Room Temperature ◽

Core Shell ◽

Shell Nanoparticles ◽

Highly Active ◽

Co Conversion ◽

Core Shell Nanoparticles

Au@CuxO core–shell nanoparticles and Au@CuxO/Al2O3 used for CO oxidation at low temperature are prepared. CO conversion on Au@CuxO/Al2O3 can reach to 38% at room temperature and the catalytic activity remains unchanged after 108 hours reaction.

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Effect on Addictives Adding of Mn-Ce/TiO2 Selective Catalytic Reduction NO by NH3 at Low-Temperature

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.955-959.25 ◽

2014 ◽

Vol 955-959 ◽

pp. 25-29 ◽

Cited By ~ 1

Author(s):

Bin Wu

Keyword(s):

Catalytic Activity ◽

Low Temperature ◽

Selective Catalytic Reduction ◽

Conversion Efficiency ◽

Catalytic Properties ◽

Catalytic Reduction ◽

Catalytic Conversion ◽

No Conversion ◽

Performance Results

Additives addition into Mn-Ce/TiO2 which had good low-temperature catalytic properties was studied, so as to improve its low-temperature anti-poisoning performance. Results showed that catalytic activity of Mn-Ce/TiO2 added additives V, Fe and Cu (short for Mn-M-Ce/TiO2 ) was improved all, compared with 95% NO conversion efficiency of Mn-Ce/TiO2 at temperature of 120°C, the ratio of Mn-M-Ce/TiO2 reached nearly 100%. Mn-Fe-Ce/TiO2 had the best single anti-poisoning ability, under the existence of 7% vapor, its catalytic conversion efficiency could be always kept over 90% at 120°C.The anti-SO2 poisoning ability at low-temperature reduced after adding additives Fe and Cu. catalytic conversion efficiency of Mn-Fe-Ce/TiO2 and Mn-Cu-Ce/TiO2 could be close to 90% at temperature of 180°C when water and SO2 exist simultaneously.

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