<abstract xmlns="http://www.w3.org/1999/xhtml">ZrO2 and a series of NiO/ZrO2 hydrogels (5 to 25 wt.% NiO) were co-precipitated with the aid of NaOH–Na2C2O4 solution. Two fluorinated hydrogels were also prepared by wet impregnation method. The samples were calcined in the temperature range of 550 to 850 °C. The surface properties of the samples were determined using DTA, XRD and nitrogen adsorption at −196 °C. The conversion of isopropanol was tested using microcatalytic pulse technique. DTA measurements showed that the addition of nickel oxide to zirconia influences the phase transition of ZrO2. XRD revealed that the tetragonal phase was formed at T ⩽ 650 °C, while a biphasic mixture was obtained at T ⩾ 750 °C. No spinel structure was detected by both DTA and XRD techniques and only traces of cubic NiO were detected for the samples containing ⩾ 15 wt.% nickel oxide and calcined at T ⩾ 750 °C. Significant changes in texture, surface acidity and catalytic activity were found as a result of the effects of thermal treatment and chemical composition. Incorporation of fluoride ions greatly increased the surface acidity and consequently enhanced the dehydration activity. It has been found that dehydration activity is related to the amount of surface acidity while the dehydrogenation of this alcohol is sensitive to NiO content.</abstract>

ZrO2 and a series of NiO/ZrO2 hydrogels (5 to 25 wt.% NiO) were co-precipitated with the aid of NaOH–Na2C2O4 solution. Two fluorinated hydrogels were also prepared by wet impregnation method. The samples were calcined in the temperature range of 550 to 850 °C. The surface properties of the samples were determined using DTA, XRD and nitrogen adsorption at −196 °C. The conversion of isopropanol was tested using microcatalytic pulse technique. DTA measurements showed that the addition of nickel oxide to zirconia influences the phase transition of ZrO2. XRD revealed that the tetragonal phase was formed at T ⩽ 650 °C, while a biphasic mixture was obtained at T ⩾ 750 °C. No spinel structure was detected by both DTA and XRD techniques and only traces of cubic NiO were detected for the samples containing ⩾ 15 wt.% nickel oxide and calcined at T ⩾ 750 °C. Significant changes in texture, surface acidity and catalytic activity were found as a result of the effects of thermal treatment and chemical composition. Incorporation of fluoride ions greatly increased the surface acidity and consequently enhanced the dehydration activity. It has been found that dehydration activity is related to the amount of surface acidity while the dehydrogenation of this alcohol is sensitive to NiO content.

Effects of thermal treatment and fluoride ion doping on surface and catalytic properties of NiO–ZrO2 catalysts

Chemistry Department, Faculty of Science, Damietta University, Damietta, 34517,

Chemistry Department, Faculty of Science, Mansoura University, Mansoura, 35511,

Materials Science-Poland

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Effects of thermal treatment and fluoride ion doping on surface and catalytic properties of NiO–ZrO catalysts

ZrO2 and a series of NiO/ZrO2 hydrogels (5 to 25 wt.% NiO) were co-precipitated with the aid of NaOH–Na2C2O4 solution. Two fluorinated hydrogels were also...

Effects of thermal treatment and fluoride ion doping on surface and catalytic properties of NiO–ZrO₂ catalysts

Article Category: Research Article

Publié en ligne: 27 avr. 2016

Pages: 53 - 62

Reçu: 30 mars 2015

Accepté: 16 nov. 2015

DOI: https://doi.org/10.1515/msp-2016-0009

Mots clés
NiO supported zirconia, acidity of solid catalyst, isopropanol conversion

© Wroclaw University of Technology

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Effects of thermal treatment and fluoride ion doping on surface and catalytic properties of NiO–ZrO2 catalysts

Article Category: Research Article

Publié en ligne: 27 avr. 2016

Pages: 53 - 62

Reçu: 30 mars 2015

Accepté: 16 nov. 2015

DOI: https://doi.org/10.1515/msp-2016-0009

Mots clésNiO supported zirconia, acidity of solid catalyst, isopropanol conversion

© Wroclaw University of Technology

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Effects of thermal treatment and fluoride ion doping on surface and catalytic properties of NiO–ZrO₂ catalysts

Mots clés
NiO supported zirconia, acidity of solid catalyst, isopropanol conversion