Conversion of methane and C5-hydrocarbons over platinum-alumina catalyst under non-oxidative conditions

The xerogels in the system 0.88 mol.% ZrO2 − 0.12 mol.% CeO2 were obtained by the method of coprecipitation in a neutral (pH = 7) and slightly alkaline (pH = 9) medium under the influence of ultrasound with the size of the agglomerates 70 – 230 nm. It is shown that the coprecipitation of hydroxides of zirconium and cerium at pH = 9 with the use of ultrasonic treatment facilitates the formation of a primary crystal is symbolic of the particles in the xerogel, whose size is ~ 5 nm, whereas the xerogel synthesized in a neutral environment consists only of the x-ray amorphous phase. The effect of pH-precipitation on deposition processes of dehydration of the xerogels and crystallization solid solution based on zirconia oxide in the metastable pseudocubic modification (с′-ZrO2) was discovered. It was found that in the temperature range 500 – 800 °C there is a phase transition с′-ZrO2 → t-ZrO2, the size of the crystallites of the formed tetragonal solid solutions is 8 and 11 nm. The method of low-temperature nitrogen adsorption were investigated dispersion properties and characteristics of the pore structure of the powders of the solid solution Zr0.88Ce0.12O2. It is determined that the specific surface area of t-ZrO2 samples obtained after firing at 800 °C is 117 and 178 m2/g, the total pore volume reaches 0.300 − 0.325 cm3/g, the pore size distribution is monomodal and is in the range of 2 − 8 nm. The effect of thermal “aging” at a temperature of 800 °C (40 h) on the structure and dispersion of the solid solution t-ZrO2 powders was studied.

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Faculty Opinions recommendation of Biological conversion of methane to methanol through genetic reassembly of native catalytic domains.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.735480092.793560182 ◽

2019 ◽

Author(s):

Hak-Sung Kim

Keyword(s):

Catalytic Domains ◽

Conversion Of Methane ◽

Biological Conversion

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Catalytically active coatings for steam reforming systems: synthesis and catalytic properties

Voprosy Materialovedeniya ◽

10.22349/1994-6716-2018-94-2-96-105 ◽

2019 ◽

pp. 96-105

Author(s):

M. L. Shishkova ◽

N. V. Yakovleva

Keyword(s):

Catalytic Properties ◽

Raw Materials ◽

Cold Gas Dynamic Spraying ◽

Hydrogen Fuel ◽

Functional Coatings ◽

Science And Engineering ◽

Powder Mixtures ◽

Conversion Of Methane ◽

Catalytically Active ◽

Metal Support

The paper considers science and engineering aspects of catalytically active compositions creation as regards immobilized catalysts for reforming hydrocarbon raw materials into hydrogen fuel. The authors investigate synthesis of catalytic powder mixtures and manufacturing of functional coatings by supersonic cold gas dynamic spraying. Research results in the field of creation of catalysts for steam conversion of methane to hydrogenous fuel on the metal support (Cr15Al15 tape support) are given. Composite powder mixtures (Ni–Al–Al(OH)3– Ca(OH)2–Mg(OH)2) were used as starting materials.

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Modelling of catalyst pellet deactivation

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19852381 ◽

1985 ◽

Vol 50 (11) ◽

pp. 2381-2395

Author(s):

Alena Brunovská ◽

Ján Buriánek ◽

Ján Ilavský ◽

Ján Valtýni

Keyword(s):

Experimental Data ◽

Numerical Results ◽

Benzene Hydrogenation ◽

Alumina Catalyst ◽

Temperature Changes ◽

Catalyst Pellet ◽

Model Equations ◽

Catalytic Poison

The diffusion and the shell progressive models of deactivation caused by irreversible chemisorption of a catalytic poison are presented for a single catalyst pellet. The method for solution of the model equations is proposed. The numerical results are compared with experimental data obtained by measuring concentration and temperature changes due to thiophene poisoning in benzene hydrogenation over a nickel-alumina catalyst.

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