Liquid-phase alkylation of phenol with long-chain olefins over WO/ZrO solid acid catalysts

Sarish, Sankaranarayana Pillai; Devassy, Biju M.; Böhringer, Walter; Fletcher, J.C.Q.; Halligudi, S.B.

doi:10.1016/j.molcata.2005.06.046

Cited by 22 publications

(34 citation statements)

References 14 publications

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“…In the FTIR spectrum of AMT1 ( The peaks belonging to the metatungstate ion were observable mostly below 1000 cm -1 , which could be identified based on the FTIR data of pure polytungstates, AMT composites and WO 3 [36,[41][42][43][44][45], as the FTIR spectrum of AMT has not been published previously.…”

Section: Characterization Of Amt1mentioning

confidence: 95%

Structure and thermal decomposition of ammonium metatungstate

Hunyadi

Sajó

Szilágyi

2013

J Therm Anal Calorim

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The structure, morphology of ammonium metatungstate (AMT), (NH 4 formed between 380-500 °C, (iv) which then transformed into the more stable m-WO 3 between 500-600 °C. As a difference in air, the as-formed NH 3 ignited with an exothermic heat effect, and nitrous oxides formed as combustion products. The thermal behavior of AMT was similar to ammonium paratungstate (APT), (NH 4 ) 10 [H 2 W 12 O 42 ]•4H 2 O, the only main difference being the lack of dry NH 3 evolution between 170-240 °C in the case of AMT.)

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Section: Characterization Of Amt1mentioning

confidence: 95%

Structure and thermal decomposition of ammonium metatungstate

Hunyadi

Sajó

Szilágyi

2013

J Therm Anal Calorim

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“…Among these modified zirconia, tungsten-deposited zirconia is the most interesting candidate because the sulfated zirconia undergoes partial deactivation due to sulfate loss during thermal treatment, 10 while the molybdenumdoped zirconia is a less active catalyst. Since the first work of Hino and Arata 11,12 demonstrating the use of tungsten-deposited zirconia as a solid acid for isomerization of light alkanes, several reactions such as oxidative desulfurization, 13 alkylation of phenols, 14 o-xylene isomerization, 15 production of aromatics from alkylfurans, 16 2-butanol dehydration, 17 among others, have been catalyzed by these materials. Herein, we focus on the industrially relevant aldoxime dehydratation and alkyne hydration reactions, for the synthesis of nitriles and carbonyl compounds, respectively.…”

Section: Introductionmentioning

confidence: 99%

One step microwave-assisted synthesis of nanocrystalline WO_x–ZrO₂ acid catalysts

Gonell

Portehault

Julián‐López

et al. 2016

Catal. Sci. Technol.

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Nanocrystalline ZrO2 and WOx-ZrO2 catalysts with a good control over the zirconia phase and the nature of the W species were synthesized in a microwave-assisted aqueous route. The zirconia polymorphs monoclinic ZrO2 (m-ZrO2) and tetragonal ZrO2 (t-ZrO2) were isolated through an accurate control of the synthetic conditions, in acidic and basic media, respectively.The evolution of the zirconia and W species under annealing of the WOx-ZrO2 nanocomposites at 500 o C and 800 o C was studied, and the resulting materials were tested as catalysts for the reactions of aldoxime dehydration and hydration of alkynes for the production of nitriles and carbonyls, respectively. In the dehydration reaction the most active species are W(VI) in tetrahedral coordination, independently of the ZrO2 polymorph, while in the hydration reaction the zirconia phase plays a key role, as the tungsten doped t-ZrO2 appears the most active catalyst.

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“…Zirconium oxide [1,2] and its composite oxides [3][4][5] have been employed as catalysts and supports because of their redox, acid/base, and thermal stabilities. For example, WO x -ZrO 2 and MoO x -ZrO 2 are typical solid acid catalysts with activity in the isomerization of n-alkanes, [3] alkylation of phenols, [4] and esterification.…”

Section: Introductionmentioning

confidence: 99%

“…For example, WO x -ZrO 2 and MoO x -ZrO 2 are typical solid acid catalysts with activity in the isomerization of n-alkanes, [3] alkylation of phenols, [4] and esterification.…”

Section: Introductionmentioning

confidence: 99%

Preparation of Porous ZrO₂‐Based Composite Oxides Containing W, Cr, Mo, or V Through a Wall Ion‐Exchange Method

et al. 2013

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Keywords: Ion exchange / Composite oxides / Microporous materials / Zirconium / Tungsten MO x -ZrO 2 (M = W, Cr, Mo, or V) composite oxides with high surface areas and hexagonal pore structures were prepared through a wall ion-exchange (WIE)-calcination method. A composite (ZS) of Zr(SO 4 ) 2 ·4H 2 O and cetyltrimethylammonium bromide with ordered hexagonal structure was cast into solutions of M oxyanions. The efficiency of the WIE treatment was first studied on the solutions of tungsten oxyanion in detail. The surface areas of tungsten-oxyanion-introduced ZSs (W-ZSs) after calcination at 673 K in air for 2 h were 3-248 m 2 g -1 depending on the pH values of the exchange solutions. The treatments at pH = 5.6-10.1 resulted in the formation of porous materials with surface areas of 38-248 m 2 g -1 IntroductionZirconium oxide [1,2] and its composite oxides [3][4][5] have been employed as catalysts and supports because of their redox, acid/base, and thermal stabilities. For example, WO x -ZrO 2 and MoO x -ZrO 2 are typical solid acid catalysts with activity in the isomerization of n-alkanes, [3] alkylation of phenols, [4] and esterification.[5] The preparation of ZrO 2 -based oxides with high surface areas has thus been widely studied. Porous ZrO 2 , [6][7][8] Zr-Cr oxide (374 m 2 g -1 ), [9] ZrO 2 -MoO 3 (275 m 2 g -1 ), [10] ZrO 2 -WO 3 (228 m 2 g -1 ), [10] ZrO 2 -WO 3 (305 m 2 g -1 ), [11] VO x -ZrO 2 (340 m 2 g -1 ), [12] and MnO 2 -ZrO 2 (256 m 2 g -1 ) [13] have been reported. However, their preparation methods were specialized for the respective materials, and no versatile method has been suggested. Therefore, ZrO 2 -based oxides of 100 m 2 g -1 or lower have been used repeatedly as catalysts by others. [14][15][16] The present group has reported the wall ion-exchange (WIE) method [17][18][19][20] as a novel preparation method of hexagonally mesostructured materials, some of which gave porous oxides with hexagonal arrays of micropores and high surface areas after calcination.[ 4970and pore sizes of approximately 1.2 nm, whereas treatments at pH = 2.5-4.8 gave surface areas of 3-18 m 2 g -1 . The predominant oxyanion in the former region was a monomeric ion, WO 4 2-. The WIE-calcination method was thus applied to the preparation of Cr-, Mo-, or V-containing ZrO 2 composite oxides in which the respective monomeric oxyanions were employed as the exchange ions by adjusting the pH values of the solutions. The surface areas of calcined Cr-, Mo-, and V-ZS were 348, 251, and 229 m 2 g -1 , respectively, and pore sizes were 1.00-1.12 nm. The WIE-calcination method was proved to be a general method for the preparation of porous ZrO 2 -based oxides.(CTAB), [21] abbreviated as ZS in this study, is a starting material of the WIE treatment, and has the composition Zr(HSO 4 )(C 19 H 42 N) 0.61 (OH) 3.57 ·2H 2 O with ordered hexagonal arrays of surfactant micelles as shown in Figure 1. The hydrogen sulfate anions (HSO 4 -) in the ZS wall can be exchanged readily for oxyanions of phosphorus, [17,20] arsenic, [18] and seleniu...

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Liquid-phase alkylation of phenol with long-chain olefins over WO/ZrO solid acid catalysts

Cited by 22 publications

References 14 publications

Structure and thermal decomposition of ammonium metatungstate

Structure and thermal decomposition of ammonium metatungstate

One step microwave-assisted synthesis of nanocrystalline WO_x–ZrO₂ acid catalysts

Preparation of Porous ZrO₂‐Based Composite Oxides Containing W, Cr, Mo, or V Through a Wall Ion‐Exchange Method

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Liquid-phase alkylation of phenol with long-chain olefins over WO/ZrO solid acid catalysts

Cited by 22 publications

References 14 publications

Structure and thermal decomposition of ammonium metatungstate

Structure and thermal decomposition of ammonium metatungstate

One step microwave-assisted synthesis of nanocrystalline WOx–ZrO2 acid catalysts

Preparation of Porous ZrO2‐Based Composite Oxides Containing W, Cr, Mo, or V Through a Wall Ion‐Exchange Method

Contact Info

Product

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One step microwave-assisted synthesis of nanocrystalline WO_x–ZrO₂ acid catalysts

Preparation of Porous ZrO₂‐Based Composite Oxides Containing W, Cr, Mo, or V Through a Wall Ion‐Exchange Method