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Patil CR, Niphadkar P, Kamble SP, Rode CV. Enhanced anisole hydroxylation over a hierarchical micro/mesoporous TS-1 catalyst. NEW J CHEM 2022. [DOI: 10.1039/d2nj01556k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Micro/mesoporous DTS-1 showed enhanced catalytic activity for anisole hydroxylation showing 54% conversion with 55% selectivity towards p-methoxyphenol.
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Affiliation(s)
- Chetana R. Patil
- Chemical Engineering and Process Development Division, CSIR-National Chemical Laboratory, Dr Homi Bhabha Road, Pune 411008, India
| | - Prashant Niphadkar
- Catalysis Pilot Plant, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, India
| | - Sanjay P. Kamble
- Chemical Engineering and Process Development Division, CSIR-National Chemical Laboratory, Dr Homi Bhabha Road, Pune 411008, India
| | - Chandrashekhar V. Rode
- Chemical Engineering and Process Development Division, CSIR-National Chemical Laboratory, Dr Homi Bhabha Road, Pune 411008, India
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2
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Influence of the Titanium Content in the Ti-MCM-41 Catalyst on the Course of the α-Pinene Isomerization Process. Catalysts 2019. [DOI: 10.3390/catal9050396] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Titanium-containing mesoporous silica catalysts with different Ti contents were prepared by the sol–gel method, whereby the molar ratios of silicon to titanium in the crystallization gel amounted to, respectively, 40:1, 30:1, 20:1 and 10:1. The produced Ti-MCM-41 materials were characterized by the following instrumental methods: XRD, UV-Vis, FT-IR, SEM, and XRF. Textural parameters were also determined for these materials by means of the N2 adsorption/desorption method. The activities of these catalysts were investigated in the α-pinene isomerization process. The most active catalyst was found to be the material with the molar ratio of Si:Ti equal to 10:1, which contained 12.09 wt% Ti. This catalyst was used in the extended studies on the α-pinene isomerization process, and the most favorable conditions for this reaction were found to be temperature of 160 °C, reaction time of 7 h, with the catalyst composition of 7.5 wt% relative to α-pinene. These studies showed that the most active catalyst, at the best reaction conditions, allowed for the attainment of 100% conversion of α-pinene over a period of 7 h. After this time the selectivities (in mol%) of the main products were as follows: camphene (35.45) and limonene (21.32). Moreover, other products with lower selectivities were formed: γ-terpinene (4.38), α-terpinene (8.12), terpinolene (11.16), p-cymene (6.61), and α-phellandrene (1.58).
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3
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Gawarecka A, Wróblewska A. Limonene oxidation over Ti-MCM-41 and Ti-MWW catalysts with t-butyl hydroperoxide as the oxidant. REACTION KINETICS MECHANISMS AND CATALYSIS 2018. [DOI: 10.1007/s11144-018-1401-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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4
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Evangelisti C, Guidotti M, Tiozzo C, Psaro R, Maksimchuk N, Ivanchikova I, Shmakov AN, Kholdeeva O. Titanium-silica catalyst derived from defined metallic titanium cluster precursor: Synthesis and catalytic properties in selective oxidations. Inorganica Chim Acta 2018. [DOI: 10.1016/j.ica.2017.06.059] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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5
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Samantaray MK, Pump E, Bendjeriou-Sedjerari A, D’Elia V, Pelletier JDA, Guidotti M, Psaro R, Basset JM. Surface organometallic chemistry in heterogeneous catalysis. Chem Soc Rev 2018; 47:8403-8437. [DOI: 10.1039/c8cs00356d] [Citation(s) in RCA: 108] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Surface organometallic chemistry has been reviewed with a special focus on environmentally relevant transformations (C–H activation, CO2conversion, oxidation).
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Affiliation(s)
- Manoja K. Samantaray
- King Abdullah University of Science and Technology (KAUST), KAUST Catalysis Center (KCC)
- Thuwal
- Saudi Arabia
| | - Eva Pump
- King Abdullah University of Science and Technology (KAUST), KAUST Catalysis Center (KCC)
- Thuwal
- Saudi Arabia
| | | | - Valerio D’Elia
- Department of Materials Science and Engineering, School of Molecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology
- WangChan
- Thailand
| | - Jérémie D. A. Pelletier
- King Abdullah University of Science and Technology (KAUST), KAUST Catalysis Center (KCC)
- Thuwal
- Saudi Arabia
| | - Matteo Guidotti
- CNR – Institute of Molecular Sciences and Technologies
- 20133 Milano
- Italy
| | - Rinaldo Psaro
- CNR – Institute of Molecular Sciences and Technologies
- 20133 Milano
- Italy
| | - Jean-Marie Basset
- King Abdullah University of Science and Technology (KAUST), KAUST Catalysis Center (KCC)
- Thuwal
- Saudi Arabia
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6
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Rajini A, Suman C, Ajay Kumar A, Suresh S, Venkatathri N. Titanium aminophosphates as efficient, economical, and recyclable catalysts for the synthesis of xanthenediones. SYNTHETIC COMMUN 2016. [DOI: 10.1080/00397911.2016.1220578] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- A. Rajini
- Department of Chemistry, National Institute of Technology, Warangal, Telangana, India
| | - C. Suman
- Department of Chemistry, National Institute of Technology, Warangal, Telangana, India
| | - A. Ajay Kumar
- Department of Chemistry, National Institute of Technology, Warangal, Telangana, India
| | - S. Suresh
- Department of Chemistry, National Institute of Technology, Warangal, Telangana, India
| | - N. Venkatathri
- Department of Chemistry, National Institute of Technology, Warangal, Telangana, India
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7
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Wróblewska A, Makuch E, Miądlicki P. The studies on the limonene oxidation over the microporous TS-1 catalyst. Catal Today 2016. [DOI: 10.1016/j.cattod.2015.11.008] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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8
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Anumula R, Adepu AK, Chirra S, Siliveri S, Narayanan V. Titanium aminophosphates: synthesis, characterization and crystal violet dye degradation studies. RSC Adv 2016. [DOI: 10.1039/c5ra22210a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Titanium aminophosphates are prepared using titanium tetraisopropoxide, orthophosphoric acid and aliphatic amines. Their detailed characterization and catalytic crystal violet dye degradation were studied.
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Affiliation(s)
- Rajini Anumula
- Department of Chemistry
- National Institute of Technology
- Warangal 506 004
- India
| | - Ajay Kumar Adepu
- Department of Chemistry
- National Institute of Technology
- Warangal 506 004
- India
| | - Suman Chirra
- Department of Chemistry
- National Institute of Technology
- Warangal 506 004
- India
| | - Suresh Siliveri
- Department of Chemistry
- National Institute of Technology
- Warangal 506 004
- India
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9
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Rajini A, Nookaraju M, Chirra S, Adepu AK, Venkatathri N. Titanium aminophosphates: synthesis, characterization and orange G dye degradation studies. RSC Adv 2015. [DOI: 10.1039/c5ra19117c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A group of titanium aminophosphate catalysts are synthesized and characterized in detail, and their catalytic application towards orange G dye degradation is studied.
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Affiliation(s)
- Anumula Rajini
- Department of Chemistry
- National Institute of Technology
- Warangal 506 004
- India
| | - Muralasetti Nookaraju
- Department of Chemistry
- Anil Neerukonda Institute of Technology and Sciences
- Vishakapatnam – 531162
- Andhra Pradesh
| | - Suman Chirra
- Department of Chemistry
- National Institute of Technology
- Warangal 506 004
- India
| | - Ajay Kumar Adepu
- Department of Chemistry
- National Institute of Technology
- Warangal 506 004
- India
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10
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Rajini A, Adepu AK, Chirra S, Venkatathri N. Porous palladium aminophosphates: synthesis, characterization, antimicrobial and cytotoxicity studies. RSC Adv 2015. [DOI: 10.1039/c5ra11923e] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Novel palladium aminophosphates have been synthesized at room temperature in solvent free condition. They are characterized in detail. Their antimicrobial and cytotoxicity studies were carried out.
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Affiliation(s)
- Anumula Rajini
- Department of Chemistry
- National Institute of Technology
- Warangal 506 004
- India
| | - Ajay Kumar Adepu
- Department of Chemistry
- National Institute of Technology
- Warangal 506 004
- India
| | - Suman Chirra
- Department of Chemistry
- National Institute of Technology
- Warangal 506 004
- India
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11
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Rajini A, Adepu AK, Chirra S, Venkatathri N. Titanium aminophosphates: synthesis, characterization, antimicrobial and cytotoxicity studies. RSC Adv 2015. [DOI: 10.1039/c5ra15084a] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Titanium aminophosphates were synthesized, characterized in detail and their antimicrobial and cytotoxicity properties were studied.
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Affiliation(s)
- Anumula Rajini
- Department of Chemistry
- National Institute of Technology
- Warangal 506 004
- India
| | - Ajay Kumar Adepu
- Department of Chemistry
- National Institute of Technology
- Warangal 506 004
- India
| | - Suman Chirra
- Department of Chemistry
- National Institute of Technology
- Warangal 506 004
- India
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12
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Wróblewska A. The epoxidation of limonene over the TS-1 and Ti-SBA-15 catalysts. Molecules 2014; 19:19907-22. [PMID: 25460313 PMCID: PMC6270933 DOI: 10.3390/molecules191219907] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2014] [Revised: 11/19/2014] [Accepted: 11/21/2014] [Indexed: 11/16/2022] Open
Abstract
Limonene belongs to a group of very important intermediates used in the production of fine chemicals. This monoterpene compound can be obtained from peels of oranges or lemon which are a (biomass) waste from the orange juice industry. Thus, limonene is a renewable, easy available and a relatively cheap compound. This work presents preliminary studies on the process of limonene epoxidation over zeolite type catalysts such as: TS-1 and Ti-SBA-15. In these studies methanol was used as a solvent and as an oxidizing agent a 60 wt % hydrogen peroxide solution was applied. The activity of each catalyst was investigated for four chosen temperatures (0 °C, 40 °C, 80 °C and 120 °C). The reaction time was changed from 0.5 to 24 h. For each catalyst the most beneficial conditions (the appropriate temperature and the reaction time) have been established. The obtained results were compared and the most active catalyst was chosen. These studies have also shown different possible ways of limonene transformation, not only in the direction of 1,2-epoxylimonene and its corresponding diol, but also in direction of carveol, carvone and perillyl alcohol-compounds with a lot of applications. The possible mechanisms of formation of the allylic oxidation products were proposed.
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Affiliation(s)
- Agnieszka Wróblewska
- Institute of Organic Chemical Technology, West Pomeranian University of Technology Szczecin, Pułaskiego 10, Szczecin 70-322, Poland.
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13
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Tiozzo C, Bisio C, Carniato F, Guidotti M. Grafted non-ordered niobium-silica materials: Versatile catalysts for the selective epoxidation of various unsaturated fine chemicals. Catal Today 2014. [DOI: 10.1016/j.cattod.2014.02.027] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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14
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15
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Tiozzo C, Bisio C, Carniato F, Gallo A, Scott SL, Psaro R, Guidotti M. Niobium–silica catalysts for the selective epoxidation of cyclic alkenes: the generation of the active site by grafting niobocene dichloride. Phys Chem Chem Phys 2013; 15:13354-62. [DOI: 10.1039/c3cp51570b] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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16
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Abstract
Mesoporous molecular sieve Ti-MCM-41 was synthesized by means of microwave radiation in domestic microwave oven using cetyltrimethyl ammonium bromide as template and ethyl orthosilicate, tetrabutyl titanate as raw materials, respectively. The sample is indeed Ti-MCM-41 after characterization by XRD, SEM, FT-IR and BET surface area. Compared with the reported synthesis methods, remarkable predominance of this method is that operation is simpler, crystallization time is shorter (only 40 min) and energy consumption is lower.
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17
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Dal Santo V, Guidotti M, Psaro R, Marchese L, Carniato F, Bisio C. Rational design of single-site heterogeneous catalysts: towards high chemo-, regio- and stereoselectivity. Proc Math Phys Eng Sci 2012. [DOI: 10.1098/rspa.2012.0056] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The main methods for the design and preparation of single-site heterogeneous catalysts on inorganic oxide supports are described and reviewed. Catalytically active metal sites can be either introduced into the framework of porous materials via direct synthesis or added to a pre-existing support by post-synthesis techniques. Particular attention is paid to selected examples where the geometry, the nature and the chemical surroundings of the active single site is a key factor to obtain catalytic systems with enhanced chemo-, regio- and stereoselectivity. The ever-increasing capabilities of ‘nanoarchitecture’ at molecular level enable chemists to build ideal catalysts for the sustainable transformation of bulky and high added-value molecules.
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Affiliation(s)
- Vladimiro Dal Santo
- CNR-Istituto di Scienze e Tecnologie Molecolari, Via C. Golgi 19, 20133 Milano, Italy
| | - Matteo Guidotti
- CNR-Istituto di Scienze e Tecnologie Molecolari, Via C. Golgi 19, 20133 Milano, Italy
| | - Rinaldo Psaro
- CNR-Istituto di Scienze e Tecnologie Molecolari, Via C. Golgi 19, 20133 Milano, Italy
| | - Leonardo Marchese
- Dipartimento di Scienze e Tecnologie Avanzate and Nano-SiSTeMI Interdisciplinary Centre, Università del Piemonte Orientale ‘A. Avogadro’, Via Bellini 25G, 15100 Alessandria, Italy
| | - Fabio Carniato
- Dipartimento di Scienze e Tecnologie Avanzate and Nano-SiSTeMI Interdisciplinary Centre, Università del Piemonte Orientale ‘A. Avogadro’, Via Bellini 25G, 15100 Alessandria, Italy
| | - Chiara Bisio
- CNR-Istituto di Scienze e Tecnologie Molecolari, Via C. Golgi 19, 20133 Milano, Italy
- Dipartimento di Scienze e Tecnologie Avanzate and Nano-SiSTeMI Interdisciplinary Centre, Università del Piemonte Orientale ‘A. Avogadro’, Via Bellini 25G, 15100 Alessandria, Italy
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Carniato F, Bisio C, Sordelli L, Gavrilova E, Guidotti M. Ti-POSS covalently immobilized onto mesoporous silica: A model for active sites in heterogeneous catalytic epoxidation. Inorganica Chim Acta 2012. [DOI: 10.1016/j.ica.2011.11.051] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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19
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Grzechowiak JR, Masalska A, Jaroszewska K, Sadowska K. Hydroconversion of 1-methylnaphthalene over Pt/SBA-15 catalysts: Effect of SBA-15 chemical composition and method of binder incorporation. Catal Today 2011. [DOI: 10.1016/j.cattod.2011.01.027] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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20
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Elías VR, Crivello ME, Herrero ER, Casuscelli SG, Eimer GA. Synthesis of Titanium-Containing Mesoporous Silicas as Catalysts for Cyclohexene Epoxidation. Ind Eng Chem Res 2009. [DOI: 10.1021/ie8018017] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Verónica R. Elías
- Centro de Investigación y Tecnología Química (CITeQ), Facultad Regional Córdoba (FRC), Universidad Tecnológica Nacional (UTN), Maestro Lopez esq. Cruz Roja s/n, C. Universitaria, 5016, Córdoba, Argentina, and Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina
| | - Mónica E. Crivello
- Centro de Investigación y Tecnología Química (CITeQ), Facultad Regional Córdoba (FRC), Universidad Tecnológica Nacional (UTN), Maestro Lopez esq. Cruz Roja s/n, C. Universitaria, 5016, Córdoba, Argentina, and Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina
| | - Eduardo R. Herrero
- Centro de Investigación y Tecnología Química (CITeQ), Facultad Regional Córdoba (FRC), Universidad Tecnológica Nacional (UTN), Maestro Lopez esq. Cruz Roja s/n, C. Universitaria, 5016, Córdoba, Argentina, and Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina
| | - Sandra G. Casuscelli
- Centro de Investigación y Tecnología Química (CITeQ), Facultad Regional Córdoba (FRC), Universidad Tecnológica Nacional (UTN), Maestro Lopez esq. Cruz Roja s/n, C. Universitaria, 5016, Córdoba, Argentina, and Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina
| | - Griselda A. Eimer
- Centro de Investigación y Tecnología Química (CITeQ), Facultad Regional Córdoba (FRC), Universidad Tecnológica Nacional (UTN), Maestro Lopez esq. Cruz Roja s/n, C. Universitaria, 5016, Córdoba, Argentina, and Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina
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21
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Eimer GA, Casuscelli SG, Chanquia CM, Elías V, Crivello ME, Herrero ER. The influence of Ti-loading on the acid behavior and on the catalytic efficiency of mesoporous Ti-MCM-41 molecular sieves. Catal Today 2008. [DOI: 10.1016/j.cattod.2007.12.096] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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22
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Mäki‐Arvela P, Holmbom B, Salmi T, Murzin DY. Recent Progress in Synthesis of Fine and Specialty Chemicals from Wood and Other Biomass by Heterogeneous Catalytic Processes. CATALYSIS REVIEWS-SCIENCE AND ENGINEERING 2007. [DOI: 10.1080/01614940701313127] [Citation(s) in RCA: 176] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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23
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Guidotti M, Ravasio N, Psaro R, Gianotti E, Coluccia S, Marchese L. Epoxidation of unsaturated FAMEs obtained from vegetable source over Ti(IV)-grafted silica catalysts: A comparison between ordered and non-ordered mesoporous materials. ACTA ACUST UNITED AC 2006. [DOI: 10.1016/j.molcata.2006.01.032] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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24
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Li G, Zhao XS. Characterization and Photocatalytic Properties of Titanium-Containing Mesoporous SBA-15. Ind Eng Chem Res 2006. [DOI: 10.1021/ie0514253] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- G. Li
- Department of Chemical and Biomolecular Engineering, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260
| | - X. S. Zhao
- Department of Chemical and Biomolecular Engineering, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260
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Kovalchuk TV, Sfihi H, Korchev AS, Kovalenko AS, Il'in VG, Zaitsev VN, Fraissard J. Synthesis, Structure, and Acidic Properties of MCM-41 Functionalized with Phosphate and Titanium Phosphate Groups. J Phys Chem B 2005; 109:13948-56. [PMID: 16852750 DOI: 10.1021/jp0580625] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Mesoporous molecular sieves Si-MCM-41 (purely siliceous) and Ti-MCM-41 (partly covered with a surface layer of TiO2) were functionalized with phosphate groups by treatment with POCl3 (denoted -MCM-41(P)and Ti-MCM-41(P), respectively). With the use of TEM, X-ray diffraction, and N2 adsorption, it was shown that the initial hexagonal structure, the high specific surface area, and porosity are retained in the functionalized materials but are not as good as in the starting materials. 1H MAS NMR and 31P MAS NMR revealed that the surface of Si-MCM-41(P) consists of silicon phosphate and pyrophosphate species. That of Ti-MCM-41(P) additionally contains titanium dihydro-, hydro-, and pyrophosphate species, the latter being predominant. TPD of adsorbed ammonia for Si-MCM-41(P) and Ti-MCM-41(P) showed that functionalization leads to the creation of moderate and strong acid sites. A combination of mesoporous structure with acidic properties makes the MCM-41 functionalized with phosphate groups promising for use as solid acid catalysts.
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Affiliation(s)
- T V Kovalchuk
- Kiev National T. Shevtchenko University, Chemistry Department, 60, Vladimirskaya str., Kiev 01033 Ukraine
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Li Y, Kim SJ. Synthesis and Characterization of Nano titania Particles Embedded in Mesoporous Silica with Both High Photocatalytic Activity and Adsorption Capability. J Phys Chem B 2005; 109:12309-15. [PMID: 16852519 DOI: 10.1021/jp0512917] [Citation(s) in RCA: 104] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
TiO(2)-xSiO(2) composites with a high specific surface area (up to 645 m(2)/g), large pore volume, and narrow distribution with average pore sizes ranging from 15 to 20 A have been synthesized by the sol-gel method. The results of characterization by XRD, BET, TEM, FTIR, and DRUV reveal that these TiO(2)-xSiO(2) composites exhibit a core/shell structure of a nano titania/Ti-O-Si species modified titania embedded in mesoporous silica. As compared to pure anatase, the embedding of nano titania particles into the mesoporous silica matrix results in a substantial blue shift of absorption edge from 3.2 to 3.54 eV and higher UV absorption intensity, which are attributed to the formation of the Ti-O-Si species modified titania in the interface between titania and silica. The as-synthesized TiO(2)-xSiO(2) composites exhibit both much higher absorption capability of organic pollutants and better photocatalytic activity for the photooxidation of benzene than pure titania. The better photocatalytic activity of as-synthesized TiO(2)-xSiO(2) composites than pure titania is attributed to their high surface area, higher UV absorption intensity, and easy diffusion of absorbed pollutants on the absorption sites to photogenerated oxidizing radicals on the photoactive sites.
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Affiliation(s)
- Yuanzhi Li
- Department of Chemistry, China Three Gorges University, Yichang, Hubei, 443002, People's Republic of China.
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28
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Moretti G, Salvi AM, Guascito MR, Langerame F. An XPS study of microporous and mesoporous titanosilicates. SURF INTERFACE ANAL 2004. [DOI: 10.1002/sia.1931] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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29
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Carati A, Ferraris G, Guidotti M, Moretti G, Psaro R, Rizzo C. Preparation and characterisation of mesoporous silica–alumina and silica–titania with a narrow pore size distribution. Catal Today 2003. [DOI: 10.1016/s0920-5861(02)00376-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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30
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Guidotti M, Conti L, Fusi A, Ravasio N, Psaro R. Diastereoselective epoxidation of hydroxy-containing unsaturated terpenes on heterogeneous titanium-catalyst. ACTA ACUST UNITED AC 2002. [DOI: 10.1016/s1381-1169(01)00484-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Schofield LJ, Kerton OJ, McMorn P, Bethell D, Ellwood S, Hutchings GJ. Oxidation of α-hydroxy containing monoterpenes using titanium silicate catalysts: comments on regioselectivity and the role of acidity. ACTA ACUST UNITED AC 2002. [DOI: 10.1039/b201724p] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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