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1

Steam reforming of methane over Ni-substituted Sr hexaaluminates

100%

Bukhtiyarova M., Ivanova A., Slavinskaya E., Kuznetsov P., Plyasova L., Stonkus O., Rogov V., Kaichev V., Noskov A.

Catalysis for Sustainable Energy

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2012

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vol. 1

11-21

EN

Ni-substituted Sr-aluminates Sr1-xNixAl11.2+xNi0.8-xO19-δ (x = 0; 0.2; 0.4; 0.8) obtained by a precipitation method and calcined at 1200°C have been characterized by different physicochemical techniques and their catalytic properties have been tested in steam reformation of methane. It has been shown that substitution of Al3+ and/or Sr2+ by Ni2+ in the aluminate structure results in changes of phase composition, specific surface area, and reducibility of samples. It has been established that the samples are not completely reduced in the temperature range of 30-900°C. The Sr1-xNixAl11.2+xNi0.8-xO19-δ (x = 0; 0.2; 0.4) catalysts are active and stable in the steam reforming of methane at 700oC: residual amount of methane is (1.1±1.0) vol.%, while the Sr1-xNixAl11.2+xNi0.8-xO19-δ (x = 0.8) sample is rapidly deactivated by coking.

2

The study of cyclooctene oxidation with molecular oxygen catalyzed by VSi2

100%

Makota O., Trach Y., Leboda R., Skubiszewska-Zięba J.

Open Chemistry

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2009

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vol. 7

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issue 4

731-738

EN

The catalytic effect of VSi2 on initial stages of the liquid-phase oxidation of cyclooctene by molecular oxygen was studied. The vanadium disilicide influences on the oxidation process in the presence of hydroperoxide. VSi2 takes part in a radical formation stage by catalysis of hydroperoxide decomposition reaction. The catalyst was investigated before and after reaction using FTIR spectroscopy. From the data obtained, the kinetic model of the catalytic oxidation process was proposed and the equation for the reaction rate was derived. The equation has described all observed dependences of reaction rate on the concentration of reactants and content of catalyst. [...]

3

Catalytic synthesis of warfarin acetals by using different heteropolyacid catalysts

88%

Gharib A., Jahangir M., Roshani M., Scheeren J., Mohadeszadeh S., Bakhtiari L., Lagzian S.

Polish Journal of Chemical Technology

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2011

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vol. 13

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issue 3

5-11

EN

In this research, we report on the synthesis of warfarin acetals by using Preyssler's anion, [NaP5W30O110]-14 and heteropolyacids (HPAs) catalysts. This reaction was performed using methanol and ethanol at reflux temperature conditions. Under these conditions we have excellent yields and high selectivity. Preyssler heteropolyacid catalyst were easily recycled recovery and reused without the loss of its catalytic activities. The synthesis of warfarin acetals has been achieved using the catalytic amounts of green, inexpensive and eco-friendly Keggin types heteropolyacids. The products were obtained in high yields.

4

Overview of the Catalytic Production of Isoprene from different raw materials; Prospects of Isoprene production from bio-ethanol.

88%

Ezinkwo G. O., Tretjakov V. F., Talyshinky R. M., Ilolov A. M., Mutombo T. A.

Catalysis for Sustainable Energy

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2012

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vol. 1

100-111

EN

Isoprene is a valuable monomer for the rubber and most chemical industries. The five carbon monomer is used to make synthetic latex similar to the natural and it is becoming a monomer of choice because of the possibility to manipulate its properties. The rapid development of synthetic rubber is a result of the huge demand for this material. Currently, SR is used practically in all spheres of industry and national economy with its global production exceeding 1.3 million tons per year In this paper, various methods for its production and their shortfalls were studied; the prospect for isoprene production from bio-ethanol was also highlighted.

5

Mathematical modeling of hydrogen production performance in thermocatalytic reactor based on the intermetallic phase of Ni3Al

88%

Badur J., Stajnke M., Ziółkowski P., Jóźwik P., Bojar Z., Ziółkowski P. J., Badur J., Stajnke M., Ziółkowski P., Jóźwik P., Bojar Z., Ziółkowski P. J.

Archives of Thermodynamics

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2019

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vol. 40

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issue 3

6

Efficient and solvent-free synthesis of 1-amidoalkyl-2-naphthols using N,N,N’,N’-tetrabromobenzene-1,3-disulfonamide

88%

Ghorbani-Vaghei R., Malaekehpour S.

Open Chemistry

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2010

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vol. 8

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issue 5

1086-1089

EN

N,N,N,’N’-Tetrabromobenzene-1,3-disulfonamide [TBBDA] is found to be a reusable catalyst for efficient synthesis of various amidoalkyl naphthols from β-naphthol, aromatic aldehydes and urea in good to high yields under solvent-free conditions. [...]

7

Acylation of aromatic compounds by acid anhydrides using Preyssler's anion [NaP5W30O110]14-and heteropolyacids as green catalysts

75%

Gharib A., Jahangir M., Scheeren J.

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EN

The Preyssler, Wells-Dowson and Keggin heteropolyacids are efficient and eco-friendly solid acid catalysts for the acylation of electron-rich aromatic compounds with acid anhydrides. The performance of different forms of heteropolyacids was compared. In all the cases, the best results were obtained using the Preyssler heteropolyacid as the catalyst. In the presence of 25 mol% (with respect to H+ equivalency) Preyssler catalyst, highly para-selective acetylation of anisole occurs using two equivalents of acetic anhydride, in 15 min at room temperature. The isolated yield of the p-methoxyacetophenone product is 98%.

8

Fast Pyrolysis of Lignin Extracted by Different Lignocellulosic Biomass after the Pretreatment Process

75%

Ulakpa W. C., Soomro S., Siddique M., Gbuvoro A.

World News of Natural Sciences

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2023

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vol. 47

1-13

EN

The manufacturing of aromatic chemicals and fuels through the rapid pyrolysis of lignin looks promising. Product selectivity and liquid yield are determined by the lignin structure and pyrolysis conditions. Lignocellulosic biomass is a carbon-containing renewable and long-lasting energy source that can be found naturally. Pyrolysis has received a lot of attention for its efficient thermal decomposition of lignocellulose biomass—which includes components of cellulose, hemicellulose, and lignin—into solid, liquid, and gas products. The formation of char is one way to describe the conversion mechanism of pyrolysis. A pre-treatment process was used to extract lignin, and the maximum yield was achieved by varying the time and temperature in a material-to-material ratio of 1:20. Without the use of any inert gas for fluidization, the first set of experiments was carried out at temperatures ranging from 400 to 650 °C. In continuous fast pyrolysis, the heating rate has an excessive rank in converting biomass into liquid, gas, and char yield when the pyrolysis temperature is increased from 600 to 700 and then 800 °C. This research provides a deeper comprehension of the interactions that take place between various components during the rapid pyrolysis of biomass. With an optimal yield of 11.96 percent being NTB, walnut shell (WNS), almond shell (AS), and babool tree bark (BTB) were produced at 600 °C with yields of 11.21, 11.73, 11.88, and 11.96%, respectively. With an optimal yield of 11.17 percent being BTB, walnut shell (WNS), almond shell (AS), and neem tree bark (NTB) were produced at 700 °C at yields of 10.89, 11.23, 11.17, and 10.88%, respectively. For walnut shell (WNS), almond shell (AS), babool tree bark (BTB), and neem tree bark (NTB), respectively, an optimal yield of 11.55 percent was obtained at 800 °C for NTB. Neem tree bark (NTB) produced the highest yield of 11.96 percent when compared to the biomass when heated to 600 °C.

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