Microspherical chromium oxide/alumina catalyst KDM for fluidized-bed isobutane dehydrogenation: Development and industrial application experience

Пахомов, Н. А.; Parakhin, O. A.; Nemykina, E. I.; Данилевич, В. В.; Чернов, М. П.; Печериченко, В. А.

doi:10.1134/s2070050412040149

Cited by 12 publications

(20 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It was shown that SiO 2 in an amount of 2.5-7.5 wt % is distributed on the surface of alumina in the form of Si(OSi) 4 and Si(OSi) 3 (O-) compounds. These SiO x -islands on the support produce additional porosity with a pore range 10-30 nm, as well as additional weak and medium acid sites.…”

Section: Discussionmentioning

confidence: 99%

“…By diffuse reflectance UV-Vis spectroscopy it was found that chromium deposition on the SiO 2 -modified supports results in an increase of Cr(III) content in comparison to the initial support. It can be seen by the increase in intensity of the signal at~17,000 cm −1 (Figure 10) which corresponds to an electronic transition 4 A 2g → 4 T 2g in the Cr(III) oct ion [26,27]. Increasing the Cr(III) content is consistent with the data of the iodometric titration, showing that the concentration of Cr(VI) (calculated as CrO 3 ) decreases from 2.5 to 1.4 wt % with an increase of SiO 2 content from 0 to 7.5 wt % (Table 5).…”

Section: Composition Crystal and Pore Structure Acidity Of Catalystsmentioning

confidence: 94%

“…The volume of the pores with diameter less than 10 nm decreases from 0.08 to 0.06 cm 3 •g −1 . SiOx-islands form additional porosity in the range of diameters 10-30 nm; the volume of these pores On the surface of the modified supports silica is distributed in the form of SiO x -fragments Si(OSi) 3 O and Si(OSi) 4 . This is indicated by the occurrence of the signals at −101 and −125 ppm on the 29 Si Magic Angle Spinning Nuclear Magnetic Resonance (MAS NMR) spectra ( Figure 5) [18,[21][22][23][24].…”

Section: Sio2-modification Of the Supportmentioning

confidence: 99%

“…The concentrations of H 2 , CH 4 , and CO were determined with the use of a column filled by 13× molecular sieves on a GH-1000 apparatus with a thermal conductivity detector.…”

Section: Catalyst Testingmentioning

confidence: 99%

“…The catalysts obtained by the first method have a low mechanical strength under the conditions of a fluidized bed and the continuous circulation between the reactor and regenerator [4]. The method of support impregnation seems the most promising.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Modification by SiO2 of Alumina Support for Light Alkane Dehydrogenation Catalysts

et al. 2016

View full text Add to dashboard Cite

Due to the continuously rising demand for C 3 -C 5 olefins it is important to improve the performance of catalysts for dehydrogenation of light alkanes. In this work the effect of modification by SiO 2 on the properties of the alumina support and the chromia-alumina catalyst was studied. SiO 2 was introduced by impregnation of the support with a silica sol. To characterize the supports and the catalysts the following techniques were used: low-temperature nitrogen adsorption; IR-spectroscopy; magic angle spinning 29 Si nuclear magnetic resonance; temperature programmed desorption and reduction; UV-Vis-, Raman-and electron paramagnetic resonance (EPR)-spectroscopy. It was shown that the modifier in amounts of 2.5-7.5 wt % distributed on the support surface in the form of SiO x -islands diminishes the interaction between the alumina support and the chromate ions (precursor of the active component). As a result, polychromates are the compounds predominantly stabilized on the surface of the modified support; under thermal activation of the catalyst and are reduced to the amorphous Cr 2 O 3 . This in turn leads to an increase in the activity of the catalyst in the dehydrogenation of isobutane.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Composition Crystal and Pore Structure Acidity Of Catalystsmentioning

confidence: 94%

Section: Sio2-modification Of the Supportmentioning

confidence: 99%

“…The concentrations of H 2 , CH 4 , and CO were determined with the use of a column filled by 13× molecular sieves on a GH-1000 apparatus with a thermal conductivity detector.…”

Section: Catalyst Testingmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Modification by SiO2 of Alumina Support for Light Alkane Dehydrogenation Catalysts

et al. 2016

View full text Add to dashboard Cite

show abstract

Formation of structural specific properties of supported Cr2O3/Al2O3 catalysts for the dehydrogenation of isobutane to isobutylene

Шутилов

Зенковец

2020

Materials Today: Proceedings

View full text Add to dashboard Cite

Recycling of Wastes from the Production of Alumina-Based Catalyst Carriers

Matveyeva

Пахомов

Murzin

2016

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

Preparation of microspherical chromia−alumina KDM-type catalysts for alkane dehydrogenation is based on utilization of an amorphous nanostructured hydroxide−oxide Al 2 O 3 −x(OH) 2 •nH 2 O (where x = 0−0.28, n = 0.03−1.8) prepared via the centrifugal thermal activation (CTA) of gibbsite. The fine fraction of this carrier is considered as industrial waste, requiring efficient recycling options, which are explored in this work. A range of physicochemical methods was applied to analyze the main properties (phase composition, morphology, reactivity, etc.) of pilot and industrial batches of gibbsite CTA products. It has been clearly shown that the properties of CTA products are dependent on the nature of gibbsite used. The largest amount of the active amorphous phase of alumina is formed using gibbsite made from concentrated nepheline. Regularities of rehydration of the CTA-products fine fraction in acidic/ alkaline media and dissolution in sulfuric acid of the fine fraction of gibbsite and the industrial CTA product were explored to prepare aluminum sulfate, which is a water purification coagulant.

show abstract

Microspherical chromium oxide/alumina catalyst KDM for fluidized-bed isobutane dehydrogenation: Development and industrial application experience

Cited by 12 publications

References 11 publications

Modification by SiO2 of Alumina Support for Light Alkane Dehydrogenation Catalysts

Modification by SiO2 of Alumina Support for Light Alkane Dehydrogenation Catalysts

Formation of structural specific properties of supported Cr2O3/Al2O3 catalysts for the dehydrogenation of isobutane to isobutylene

Recycling of Wastes from the Production of Alumina-Based Catalyst Carriers

Contact Info

Product

Resources

About