<abstract xmlns="http://www.w3.org/1999/xhtml">

<p>High skeletal titanium content, open mesoporous TS-1 titanosilica molecular sieves with more accessible active centres exhibit higher catalytic activity, target product selectivity and resistance to coking deactivation in green catalytic oxidation reactions using hydrogen peroxide as oxidant. In this paper, TS-1 titania-silica molecular sieves without anatase, with the highest theoretical skeletal titanium content (2.0 wt%) and open mesopores (mesopore volume 0.71 cm<sup>3</sup>/g) were synthesised based on the ageing dry gel limited domain conversion method invented in previous research work. The intrinsic kinetics of the catalytic reaction of phenol with hydrogen peroxide for direct hydroxylation of benzenes was investigated. The effects of stirring rate, phenol concentration, hydrogen peroxide concentration, catalyst dosage and reaction temperature on the initial conversion rate of phenol were investigated, and the experimental data were fitted with a power function equation to obtain the intrinsic kinetic equation of the catalyst <inline-formula>
<alternatives>
<inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="graphic/j_amns.2023.2.00539_eq_001.png"></inline-graphic>
<math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mrow><mo>(</mo><mrow><mtext>r</mtext><mo>=</mo><mn>2.98</mn><mo>×</mo><msup><mrow><mrow><mn>10</mn></mrow></mrow><mn>6</mn></msup><mi> </mi><mo>exp</mo><mi> </mi><mrow><mo>(</mo><mrow><mo>−</mo><mfrac><mrow><mn>56.43</mn><mo>×</mo><msup><mrow><mrow><mn>10</mn></mrow></mrow><mn>3</mn></msup></mrow><mrow><mi>R</mi><mi>T</mi></mrow></mfrac></mrow><mo>)</mo></mrow><msup><mrow><mi>c</mi></mrow><mrow><mn>1.07</mn></mrow></msup><mrow><mo>(</mo><mrow><mtext>Phenol</mtext></mrow><mo>)</mo></mrow><msup><mrow><mi>c</mi></mrow><mrow><mn>0.10</mn></mrow></msup><mrow><mo>(</mo><mrow><msub><mrow><mtext>H</mtext></mrow><mn>2</mn></msub><msub><mrow><mtext>O</mtext></mrow><mn>2</mn></msub></mrow><mo>)</mo></mrow></mrow><mo>)</mo></mrow></mrow></math>
<tex-math>\left( {{\rm{r}} = 2.98 \times {{10}^6}\,\exp \,\left( { - {{56.43 \times {{10}^3}} \over {RT}}} \right){c^{1.07}}\left( {{\rm{Phenol}}} \right){c^{0.10}}\left( {{{\rm{H}}_2}{{\rm{O}}_2}} \right)} \right)</tex-math>
</alternatives>
</inline-formula>. Under the condition of eliminating the effect of internal and external diffusion, the reaction was 1.07 and 0.10 for phenol and hydrogen peroxide, respectively, with a reaction activation energy of 56.43 kJ/mol. This study provides a theoretical basis for the reactor and process design of hydroxylation of phenol to benzenediol based on this new catalyst.</p>
</abstract>

High skeletal titanium content, open mesoporous TS-1 titanosilica molecular sieves with more accessible active centres exhibit higher catalytic activity, target product selectivity and resistance to coking deactivation in green catalytic oxidation reactions using hydrogen peroxide as oxidant. In this paper, TS-1 titania-silica molecular sieves without anatase, with the highest theoretical skeletal titanium content (2.0 wt%) and open mesopores (mesopore volume 0.71 cm3/g) were synthesised based on the ageing dry gel limited domain conversion method invented in previous research work. The intrinsic kinetics of the catalytic reaction of phenol with hydrogen peroxide for direct hydroxylation of benzenes was investigated. The effects of stirring rate, phenol concentration, hydrogen peroxide concentration, catalyst dosage and reaction temperature on the initial conversion rate of phenol were investigated, and the experimental data were fitted with a power function equation to obtain the intrinsic kinetic equation of the catalyst 


(r=2.98×106 exp (−56.43×103RT)c1.07(Phenol)c0.10(H2O2))
\left( {{\rm{r}} = 2.98 \times {{10}^6}\,\exp \,\left( { - {{56.43 \times {{10}^3}} \over {RT}}} \right){c^{1.07}}\left( {{\rm{Phenol}}} \right){c^{0.10}}\left( {{{\rm{H}}_2}{{\rm{O}}_2}} \right)} \right)

. Under the condition of eliminating the effect of internal and external diffusion, the reaction was 1.07 and 0.10 for phenol and hydrogen peroxide, respectively, with a reaction activation energy of 56.43 kJ/mol. This study provides a theoretical basis for the reactor and process design of hydroxylation of phenol to benzenediol based on this new catalyst.

Kinetics of phenol hydroxylation reaction of open mesoporous TS-1 with high backbone titanium content

Liaoning Provincial key Laboratory for Synthesis and Preparation of Special Functional Materials

Shenyang University of Chemical Technology

Shenyang National Laboratory for Materials Science

University of Science and Technology of China

Shenyang Key Laboratory for New Functional Coating Materials

Applied Mathematics and Nonlinear Sciences

This work is licensed under the Creative Commons Attribution 4.0 International License.

High skeletal titanium content, open mesoporous TS-1 titanosilica molecular sieves with more accessible active centres exhibit higher catalytic activity,...

Kinetics of phenol hydroxylation reaction of open mesoporous TS-1 with high backbone titanium content

Publié en ligne: 09 oct. 2023

Pages: -

Reçu: 16 déc. 2022

Accepté: 19 avr. 2023

DOI: https://doi.org/10.2478/amns.2023.2.00539

Mots clés
TS-1, Aged dry gel domain-limited transformation, Phenol hydroxylation, Intrinsic kinetics

© 2023 Shuai Wang et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.

Kinetics of phenol hydroxylation reaction of open mesoporous TS-1 with high backbone titanium content

Publié en ligne: 09 oct. 2023

Pages: -

Reçu: 16 déc. 2022

Accepté: 19 avr. 2023

DOI: https://doi.org/10.2478/amns.2023.2.00539

Mots clésTS-1, Aged dry gel domain-limited transformation, Phenol hydroxylation, Intrinsic kinetics

© 2023 Shuai Wang et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.

Mots clés
TS-1, Aged dry gel domain-limited transformation, Phenol hydroxylation, Intrinsic kinetics