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Velinova R, Todorova S, Kovacheva D, Kolev H, Karakirova Y, Markov P, Tumbalova K, Ivanov G, Naydenov A. Effect of TiO 2 on Pd/La 2O 3-CeO 2-Al 2O 3 Systems during Catalytic Oxidation of Methane in the Presence of H 2O and SO 2. MATERIALS (BASEL, SWITZERLAND) 2023; 16:6784. [PMID: 37895766 PMCID: PMC10608221 DOI: 10.3390/ma16206784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 10/10/2023] [Accepted: 10/18/2023] [Indexed: 10/29/2023]
Abstract
New results on the effect of TiO2 on Pd/La2O3-CeO2-Al2O3 systems for catalytic oxidation of methane in the presence of H2O and SO2 have been received. Low-temperature N2-adsorption, XRD, SEM, HRTEM, XPS, EPR and FTIR techniques were used to characterize the catalyst. The presence of Ce3+ on the catalytic surface and in the volume near the lantana was revealed by EPR and XPS. After aging, the following changes are observed: (i) agglomeration of the Pd-clusters (from 8 nm to 12 nm); (ii) transformation of part of the TiO2 from anatase to larger particles of rutile; and (iii)-the increase in PdO/Pd-ratio above its optimum. The modification by Ti of the La2O3-CeO2-Al2O3 system leads to higher resistance towards the presence of SO2 most likely due to the prevailing formation of unstable surface sulfites instead of thermally stable sulfates. Based on kinetic model calculations, the reaction pathway over the Pd/La2O3-CeO2-TiO2-Al2O3 catalyst follows the Mars-van Krevelen mechanism. For evaluation of the possible practical application of the obtained material, a sample of Pd/La2O3-CeO2-TiO2-Al2O3, supported on rolled aluminum-containing stainless steel (Aluchrom VDM®), was prepared and tested. Methane oxidation in an industrial-scale monolithic reactor was simulated using a two-dimensional heterogeneous reactor model.
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Affiliation(s)
- Ralitsa Velinova
- Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., bl. 11, 1113 Sofia, Bulgaria
| | - Silviya Todorova
- Institute of Catalysis, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., bl. 11, 1113 Sofia, Bulgaria
| | - Daniela Kovacheva
- Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., bl. 11, 1113 Sofia, Bulgaria
| | - Hristo Kolev
- Institute of Catalysis, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., bl. 11, 1113 Sofia, Bulgaria
| | - Yordanka Karakirova
- Institute of Catalysis, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., bl. 11, 1113 Sofia, Bulgaria
| | - Pavel Markov
- Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., bl. 11, 1113 Sofia, Bulgaria
| | - Katerina Tumbalova
- Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., bl. 11, 1113 Sofia, Bulgaria
| | - Georgi Ivanov
- Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., bl. 11, 1113 Sofia, Bulgaria
| | - Anton Naydenov
- Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., bl. 11, 1113 Sofia, Bulgaria
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2
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Zhao Y, Xi C, Gao S, Wang Y, Wang H, Sun P, Wu Z. Ru-based monolithic catalysts for the catalytic oxidation of chlorinated volatile organic compounds. RSC Adv 2023; 13:7037-7044. [PMID: 36874937 PMCID: PMC9977393 DOI: 10.1039/d2ra07823f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Accepted: 02/16/2023] [Indexed: 03/05/2023] Open
Abstract
A series of cordierite monolithic catalysts with Ru species supported on different available low-cost carriers were prepared and investigated for the elimination of CVOCs. The results suggest that the monolithic catalyst with Ru species supported on anatase TiO2 carrier with abundant acidic sites exhibited the desired catalytic activity for DCM oxidation with the T 90% value of 368 °C. In addition, a pseudo-boehmite sol used as binder was introduced into the preparation of the monolithic catalysts to further improve the adhesion between the powder catalysts and cordierite honeycomb carrier. The results suggest that although the T 50% and T 90% of the Ru/TiO2/PB/Cor shifted to higher temperature of 376 and 428 °C, the weight loss of the coating for the Ru/TiO2/PB/Cor catalyst was improved and decreased to 6.5 wt%. Also, the as-obtained Ru/TiO2/PB/Cor catalyst exhibited ideal catalytic properties for the abatement of ethyl acetate and ethanol, indicating that the catalyst can meet the demand for the treatment of actual multi-component industrial gas.
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Affiliation(s)
- Yemin Zhao
- Department of Environmental Engineering, Zhejiang University Hangzhou 310058 P. R. China.,Zhejiang Tianlan Environmental Protection Technology Co., Ltd. Hangzhou 311202 China .,Zhejiang Provincial Engineering Research Center of Industrial Boiler & Furnace Flue Gas Pollution Control 866 Yuhangtang Road Hangzhou 310058 P. R. China
| | - Chao Xi
- Zhejiang Tianlan Environmental Protection Technology Co., Ltd. Hangzhou 311202 China .,Zhejiang Provincial Engineering Research Center of Industrial Boiler & Furnace Flue Gas Pollution Control 866 Yuhangtang Road Hangzhou 310058 P. R. China
| | - Shan Gao
- Zhejiang Tianlan Environmental Protection Technology Co., Ltd. Hangzhou 311202 China .,Zhejiang Provincial Engineering Research Center of Industrial Boiler & Furnace Flue Gas Pollution Control 866 Yuhangtang Road Hangzhou 310058 P. R. China
| | - Yuejun Wang
- Zhejiang Tianlan Environmental Protection Technology Co., Ltd. Hangzhou 311202 China .,Zhejiang Provincial Engineering Research Center of Industrial Boiler & Furnace Flue Gas Pollution Control 866 Yuhangtang Road Hangzhou 310058 P. R. China
| | - Haiqiang Wang
- Department of Environmental Engineering, Zhejiang University Hangzhou 310058 P. R. China.,Zhejiang Provincial Engineering Research Center of Industrial Boiler & Furnace Flue Gas Pollution Control 866 Yuhangtang Road Hangzhou 310058 P. R. China
| | - Pengfei Sun
- Department of Chemistry, Key Laboratory of Surface & Interface Science of Polymer Materials of Zhejiang Province, Zhejiang Sci-Tech University Hangzhou 310018 China
| | - Zhongbiao Wu
- Department of Environmental Engineering, Zhejiang University Hangzhou 310058 P. R. China.,Zhejiang Provincial Engineering Research Center of Industrial Boiler & Furnace Flue Gas Pollution Control 866 Yuhangtang Road Hangzhou 310058 P. R. China
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3
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Li X, Chen Y, Chen Z, Guo H, Yang S, Ma X. The recent progress on gaseous chlorinated aromatics removal for environmental applications. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2022.121364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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4
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Gannoun C, Ghorbel A, Gaigneaux EM. Influence of zirconia addition in TiO 2 and TiO 2-CeO 2 aerogels on the textural, structural and catalytic properties of supported vanadia in chlorobenzene oxidation. RSC Adv 2022; 12:10924-10932. [PMID: 35425082 PMCID: PMC8988661 DOI: 10.1039/d1ra08611a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 03/02/2022] [Indexed: 01/16/2023] Open
Abstract
This paper studies the effect of the direct incorporation of ZrO2 in TiO2 and TiO2-CeO2 aerogel supports prepared by sol-gel route on the physico-chemical and catalytic properties of supported vanadia catalysts in the total oxidation of chlorobenzene. The obtained catalysts have been characterized by means of ICP-AES, N2 adsorption-desorption at 77 K, XRD, XPS, H2-TPR and NH3-TPD. The results revealed that Zr-doped V2O5 based catalyst is beneficial for the improvement of catalytic properties in chlorobenzene total oxidation. In particular, in the absence of cerium groups, this beneficial effect is correlated with the better acidic properties or/and the stabilization of the V2O5 active phase in a higher oxidation state. However, in the case of cerium rich catalyst, this positive effect is much stronger thanks to the enhanced redox properties of V2O5/TiO2-CeO2-ZrO2.
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Affiliation(s)
- Chiraz Gannoun
- Centre National des Recherches en Sciences des Matériaux (CNRSM) Technopôle Borj Cedria, BP73 8027 Soliman Tunisia
| | - Abdelhamid Ghorbel
- Laboratoire de Chimie des Matériaux et Catalyse, Département de Chimie, Faculté des Sciences de Tunis, Campus Universitaire 2092 El Manar Tunis Tunisia
| | - Eric M Gaigneaux
- Université Catholique de Louvain, Institute of Condensed Matter and Nanosciences (IMCN), Division "Molecular Chemistry, Materials and Catalysis (MOST)" Place Louis Pasteur 1 L4.01.09 B-1348 Louvain-la-Neuve Belgium
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5
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Noble-Metal-Based Catalytic Oxidation Technology Trends for Volatile Organic Compound (VOC) Removal. Catalysts 2022. [DOI: 10.3390/catal12010063] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Volatile organic compounds (VOCs) are toxic and are considered the most important sources for the formation of photochemical smog, secondary organic aerosols (SOAs), and ozone. These can also greatly affect the environment and human health. For this reason, VOCs are removed by applying various technologies or reused after recovery. Catalytic oxidation for VOCs removal is widely applied in the industry and is regarded as an efficient and economical method compared to other VOCs removal technologies. Currently, a large amount of VOCs are generated in industries with solvent-based processes, and the ratio of aromatic compounds is high. This paper covers recent catalytic developments in VOC combustion over noble-metal-based catalysts. In addition, this report introduces recent trends in the development of the catalytic mechanisms of VOC combustion and the deactivation of catalysts, such as coke formation, poisoning, sintering, and catalyst regeneration. Since VOC oxidation by noble metal catalysts depends on the support of and mixing catalysts, an appropriate catalyst should be used according to reaction characteristics. Moreover, noble metal catalysts are used together with non-noble metals and play a role in the activity of other catalysts. Therefore, further elucidation of their function and catalytic mechanism in VOC removal is required.
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6
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Santos DFM, Soares OSGP, Figueiredo JL, Pereira MFR. Optimization of the preparation conditions of cordierite honeycomb monoliths washcoated with cryptomelane-type manganese oxide for VOC oxidation. ENVIRONMENTAL TECHNOLOGY 2021; 42:2504-2515. [PMID: 31854269 DOI: 10.1080/09593330.2019.1705398] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 12/10/2019] [Indexed: 06/10/2023]
Abstract
Ceramic honeycomb monoliths were washcoated with cryptomelane-type manganese oxides and their catalytic performance was evaluated in the oxidation of ethyl acetate. The effect of a mixture of ethyl acetate with toluene and of the presence of water vapour was also assessed.Different coating parameters, namely size of catalyst particles, number of immersions in the washcoating solution, presence of an initial coating with alumina, calcination temperature of this coating, as well as the amount of binding agent and ethanol in the washcoating solution were studied and optimized based on the catalytic activity of the structured catalyst. Small particles are required for a correct impregnation; however, since the smallest particles are less active, an intermediate size achieved the best catalytic results. Increasing the number of immersions over 3 did not significantly increase the catalytic activity of the structured catalyst. The presence of an initial coating with alumina and a binding agent (colloidal alumina) in the washcoating solution was found essential to increase the activity, whereas increasing the calcination temperature after the initial alumina coating above 500°C decreased the activity of the catalyst. The presence of ethanol in the washcoating solution did not significantly improve the activity of the structured catalyst.The optimized structured catalyst presented high catalytic activity in the removal of ethyl acetate (90% conversion into CO2 at 256°C) and high stability during 100 h of reaction. The addition of toluene or water vapour in the feed gas did not significantly affect the activity of the coated monolith.
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Affiliation(s)
- Diogo F M Santos
- Laboratory of Separation and Reaction Engineering - Laboratory of Catalysis and Materials (LSRE-LCM), Faculdade de Engenharia, Universidade do Porto, Porto, Portugal
| | - Olívia S G P Soares
- Laboratory of Separation and Reaction Engineering - Laboratory of Catalysis and Materials (LSRE-LCM), Faculdade de Engenharia, Universidade do Porto, Porto, Portugal
| | - José L Figueiredo
- Laboratory of Separation and Reaction Engineering - Laboratory of Catalysis and Materials (LSRE-LCM), Faculdade de Engenharia, Universidade do Porto, Porto, Portugal
| | - Manuel Fernando R Pereira
- Laboratory of Separation and Reaction Engineering - Laboratory of Catalysis and Materials (LSRE-LCM), Faculdade de Engenharia, Universidade do Porto, Porto, Portugal
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7
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Wei J, Ma D, Ma X, Sheng Q, Sun X, Li J, Liu X, Shen J, Zheng M, Wang L. New insight into increased toxicity during ozonation of chlorophenol: The significant contribution of oxidizing intermediates. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 769:144569. [PMID: 33477043 DOI: 10.1016/j.scitotenv.2020.144569] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 12/09/2020] [Accepted: 12/13/2020] [Indexed: 06/12/2023]
Abstract
Biological safety evaluation and toxic by-products identification are critical issues in the partial oxidation process. Previous studies have shown that the whole toxicity increased in the effluent of an ozonation process for chlorophenols removal. Here, this study systematically investigated the changes of acute toxicity during the ozonation of 3-chlorophenol under four key operational conditions, including initial 3-chlorophenol concentration (20-60 mg/L), ozone concentration (14-42 mg/L), reaction pH (3-10) and ozonation time (0-50 min). The results found that the ozonation process induced a significant increase in the acute toxicity, followed by its gradual decrease. The observation of higher acute toxicity increase generally happened at higher initial 3-chlorophenol concentration, lower ozone concentration and lower reaction pH. At the toxicity peaks, the oxidizing intermediates posed acute toxicity equal to 65.8%-96.3% of the whole toxicity. Among them, free active chlorine (FAC) contributed 21.4%-51.6%, and its concentrations significantly correlated to the acute toxicity change. Therefore, two possible FAC generation pathways initiated by ozone molecule were proposed: (i) bond breaking of the oxychloride complex formed by the combination of chloride ion and zwitterion; or (ii) hydrolysis of ozonides formed by the electrophilic reaction of ozone molecule. Together, these results firstly revealed the significant toxicity contribution of oxidizing intermediates during the ozonation of chlorophenols, supporting further development of safe and effective ozone-based water treatment schemes.
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Affiliation(s)
- Jianjian Wei
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, Jiangsu Province, China
| | - Dehua Ma
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, Jiangsu Province, China.
| | - Xuerou Ma
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, Jiangsu Province, China
| | - Qian Sheng
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, Jiangsu Province, China
| | - Xiuyun Sun
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, Jiangsu Province, China
| | - Jiansheng Li
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, Jiangsu Province, China
| | - Xiaodong Liu
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, Jiangsu Province, China
| | - Jinyou Shen
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, Jiangsu Province, China.
| | - Min Zheng
- Advanced Water Management Centre, University of Queensland, St Lucia, QLD 4072, Australia
| | - Lianjun Wang
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, Jiangsu Province, China
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8
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Li N, Xing X, Cheng J, Zhang Z, Hao Z. Influence of oxygen and water content on the formation of polychlorinated organic by-products from catalytic degradation of 1,2-dichlorobenzene over a Pd/ZSM-5 catalyst. JOURNAL OF HAZARDOUS MATERIALS 2021; 403:123952. [PMID: 33264996 DOI: 10.1016/j.jhazmat.2020.123952] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 08/30/2020] [Accepted: 09/03/2020] [Indexed: 06/12/2023]
Abstract
Understanding the generation and influence mechanism of polychlorinated organic by-products during the catalytic degradation of chlorinated volatile organic compounds (CVOCs) is essential to the safe and environmentally friendly treatment of those pollutants. In this study, a systematic investigation of the catalytic oxidation of 1,2-dichlorobenzene (1,2-DCB) was conducted using various oxygen and water contents over a Pd/ZSM-5(25) catalyst. It was found that decreasing the oxygen content and increasing the water content resulted in the improvement of the 1,2-DCB catalytic activity, while the amount and variety of polychlorinated organic by-products decreased. More importantly, when water was the sole oxidant, the Pd/ZSM-5(25) catalyst also demonstrated high activity towards 1,2-DCB catalytic degradation. Only chlorobenzene and 1,3-dichlorobenzene were detected as by-products. X-ray photoelectron spectra (XPS) and UV-vis DRS spectra results indicated that the polychlorinated organic by-products were suppressed mainly due to inhibition of the chlorination of the palladium species by regulating the oxygen and water content in the reaction atmosphere. Similar surface species were formed under aerobic and anaerobic atmospheres via the study of the in situ FTIR spectra. We therefore proposed that 1,2-DCB undergoes similar catalytic degradation reaction mechanisms under both aerobic and anaerobic conditions.
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Affiliation(s)
- Na Li
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, Research Center for Environmental Material and Pollution Control Technology, University of Chinese Academy of Sciences, Beijing 101408, PR China; Key Laboratory of Environmental Nanotechnology and Health Effects, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China
| | - Xin Xing
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, Research Center for Environmental Material and Pollution Control Technology, University of Chinese Academy of Sciences, Beijing 101408, PR China; Key Laboratory of Environmental Nanotechnology and Health Effects, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China
| | - Jie Cheng
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, Research Center for Environmental Material and Pollution Control Technology, University of Chinese Academy of Sciences, Beijing 101408, PR China.
| | - Zhongshen Zhang
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, Research Center for Environmental Material and Pollution Control Technology, University of Chinese Academy of Sciences, Beijing 101408, PR China
| | - Zhengping Hao
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, Research Center for Environmental Material and Pollution Control Technology, University of Chinese Academy of Sciences, Beijing 101408, PR China; Key Laboratory of Environmental Nanotechnology and Health Effects, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China
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9
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Wu X, Han R, Liu Q, Su Y, Lu S, Yang L, Song C, Ji N, Ma D, Lu X. A review of confined-structure catalysts in the catalytic oxidation of VOCs: synthesis, characterization, and applications. Catal Sci Technol 2021. [DOI: 10.1039/d1cy00478f] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
This picture depicts the process of the catalytic oxidation of VOCs on confined-structure catalysts, which possess excellent activity and can effectively protect the active phase from aggregation and poisoning.
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10
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Li N, Cheng J, Xing X, Sun Y, Hao Z. Distribution and formation mechanisms of polychlorinated organic by-products upon the catalytic oxidation of 1,2-dichlorobenzene with palladium-loaded catalysts. JOURNAL OF HAZARDOUS MATERIALS 2020; 393:122412. [PMID: 32126429 DOI: 10.1016/j.jhazmat.2020.122412] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Revised: 02/24/2020] [Accepted: 02/25/2020] [Indexed: 06/10/2023]
Abstract
Clarifying the oxidative products and their formation mechanisms in the catalytic oxidation of chlorinated volatile organic compounds is important to provide detailed understanding of the degradation of pollutants with the simultaneous removal of secondary pollutants. In this study, catalytic oxidation of 1,2-dichlorobenzene (1,2-DCB) using commonly commercial catalysts (Pd/γ-Al2O3, Pd/ZSM-5, and Pd/SiO2) was investigated. During the oxidation processes, substantial amounts of polychlorinated organic by-products, such as trichlorobenzene, tetrachlorobenzene and pentachlorobenzene, were detected. The reaction temperature and types of supports played a vital role in the formation of chlorinated organic by-products. With an increase of the reaction temperature, the degree of chlorination of the organic by-products increased gradually, and the concentration of polychlorinated organic by-products was increased sharply at low temperatures and then decreased when the reaction temperature was above 450 °C. Meanwhile, the amounts of polychlorinated organic by-products increased with an increasing silicate-to-aluminium ratio. Furthermore, based on the distribution of chlorinated organic by-products and characterization results of pyridine from FTIR, XPS, UV-vis-DRs, and in situ FTIR, the formation mechanisms of the polychlorinated organic compounds were proposed.
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Affiliation(s)
- Na Li
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, Research Center for Environmental Material and Pollution Control Technology, University of Chinese Academy of Sciences, Beijing 101408, PR China; Key Laboratory of Environmental Nanotechnology and Health Effects, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China
| | - Jie Cheng
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, Research Center for Environmental Material and Pollution Control Technology, University of Chinese Academy of Sciences, Beijing 101408, PR China.
| | - Xin Xing
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, Research Center for Environmental Material and Pollution Control Technology, University of Chinese Academy of Sciences, Beijing 101408, PR China; Key Laboratory of Environmental Nanotechnology and Health Effects, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China
| | - Yonggang Sun
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, Research Center for Environmental Material and Pollution Control Technology, University of Chinese Academy of Sciences, Beijing 101408, PR China
| | - Zhengping Hao
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, Research Center for Environmental Material and Pollution Control Technology, University of Chinese Academy of Sciences, Beijing 101408, PR China; Key Laboratory of Environmental Nanotechnology and Health Effects, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China
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11
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Abstract
A series of Pd-TiO2/Pd-Ce/TiO2 catalysts were prepared by an equal volume impregnation method. The effects of different Pd loadings on the catalytic activity of chlorobenzene (CB) were investigated, and the results showed that the activity of the 0.2%-0.3% Pd/TiO2 catalyst was optimal. The effect of Ce doping enhanced the catalytic activity of the 0.2% Pd-0.5% Ce/TiO2 catalyst. The characterization of the catalysts using BET, TEM, H2-TPR, and O2-TPD showed that the oxidation capacity was enhanced, and the catalytic oxidation efficiency was improved due to the addition of Ce. Ion chromatography and Gas Chromatography-Mass Spectrometer results showed that small amounts of dichlorobenzene (DCB) and trichlorobenzene (TCB) were formed during the decomposition of CB. The results also indicated that the calcination temperature greatly influenced the catalyst activity and a calcination temperature of 550 °C was the best. The concentration of CB affected its decomposition, but gas hourly space velocity had little effect. H2-TPR indicated strong metal–support interactions and increased dispersion of PdO in the presence of Ce. HRTEM data showed PdO with a characteristic spacing of 0.26 nm in both 0.2% Pd /TiO2 and 0.2% Pd-0.5% Ce/TiO2 catalysts. The average sizes of PdO nanoparticles in the 0.2% Pd/TiO2 and 0.2% Pd-0.5% Ce/TiO2 samples were 5.8 and 4.7 nm, respectively. The PdO particles were also deposited on the support and they were separated from each other in both catalysts.
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12
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Li G, Wang L, Wen C, Li F, Wu P, Wang B, Shen K, Zhang Y, Zhang S, Xiao R. Deep insight into the catalytic removal mechanism of a multi-active center catalyst for chlorobenzene: an experiment and density functional theory study. Catal Sci Technol 2020. [DOI: 10.1039/d0cy01372b] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Catalytic oxidation is a promising dioxin purification removal technique due to high efficiency and low consumption, as well as no secondary pollution.
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13
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Wan J, Yang P, Guo X, Zhou R. Investigation on the structure-activity relationship of Nb2O5 promoting CeO2-CrOx-Nb2O5 catalysts for 1,2-dichloroethane elimination. MOLECULAR CATALYSIS 2019. [DOI: 10.1016/j.mcat.2019.03.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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14
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Qiu Y, Ye N, Situ D, Zuo S, Wang X. Study of Catalytic Combustion of Chlorobenzene and Temperature Programmed Reactions over CrCeOx/AlFe Pillared Clay Catalysts. MATERIALS (BASEL, SWITZERLAND) 2019; 12:E728. [PMID: 30832365 PMCID: PMC6427678 DOI: 10.3390/ma12050728] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 02/23/2019] [Accepted: 02/25/2019] [Indexed: 11/29/2022]
Abstract
In this study, both AlFe composite pillaring agents and AlFe pillared clays (AlFe-PILC) were synthesized via a facile process developed by our group, after which mixed Cr and Ce precursors were impregnated on AlFe-PILC. Catalytic combustion of organic pollutant chlorobenzene (CB) on CrCe/AlFe-PILC catalysts were systematically studied. AlFe-PILC displayed very high thermal stability and large BET surface area (SBET). After 4 h of calcination at 550 °C, the basal spacing (d001) and SBET of AlFe-PILC was still maintained at 1.91 nm and 318 m²/g, respectively. Large SBET and d001-value, along with the strong interaction between the carrier and active components, improved the adsorption/desorption of CB and O₂. When the desorption temperatures of CB and O₂ got closer to the CB combustion temperature, the CB conversion could be increased to a higher level. CB combustion on CrCe/AlFe-PILC catalyst was determined using a Langmuir⁻Hinshelwood mechanism. Adsorption/desorption/oxidation properties were critical to design highly efficient catalysts for CB degradation. Besides, CrCe/AlFe-PILC also displayed good durability for CB combustion, whether in a humid environment or in the presence of volatile organic compound (VOC), making the catalyst an excellent material for eliminating chlorinated VOCs.
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Affiliation(s)
- Yingnan Qiu
- Zhejiang Key Laboratory of Alternative Technologies for Fine Chemicals Process, Shaoxing University, Shaoxing 312000, China.
| | - Na Ye
- Zhejiang Key Laboratory of Alternative Technologies for Fine Chemicals Process, Shaoxing University, Shaoxing 312000, China.
| | - Danna Situ
- Zhejiang Key Laboratory of Alternative Technologies for Fine Chemicals Process, Shaoxing University, Shaoxing 312000, China.
| | - Shufeng Zuo
- Zhejiang Key Laboratory of Alternative Technologies for Fine Chemicals Process, Shaoxing University, Shaoxing 312000, China.
| | - Xianqin Wang
- Department of Chemical, Biological and Pharmaceutical Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA.
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He C, Cheng J, Zhang X, Douthwaite M, Pattisson S, Hao Z. Recent Advances in the Catalytic Oxidation of Volatile Organic Compounds: A Review Based on Pollutant Sorts and Sources. Chem Rev 2019; 119:4471-4568. [DOI: 10.1021/acs.chemrev.8b00408] [Citation(s) in RCA: 769] [Impact Index Per Article: 153.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Chi He
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, University of Chinese Academy of Sciences, Beijing 101408, P.R. China
- Department of Environmental Science and Engineering, State Key Laboratory of Multiphase Flow in Power Engineering, School of Energy and Power Engineering, Xi’an Jiaotong University, Xi’an 710049, Shaanxi, P.R. China
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, U.K
| | - Jie Cheng
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, University of Chinese Academy of Sciences, Beijing 101408, P.R. China
| | - Xin Zhang
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, University of Chinese Academy of Sciences, Beijing 101408, P.R. China
| | - Mark Douthwaite
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, U.K
| | - Samuel Pattisson
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, U.K
| | - Zhengping Hao
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, University of Chinese Academy of Sciences, Beijing 101408, P.R. China
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16
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Feng Z, Gao C, Ma X, Zhan J. Well-dispersed Pd nanoparticles on porous ZnO nanoplates via surface ion exchange for chlorobenzene-selective sensor. RSC Adv 2019; 9:42351-42359. [PMID: 35542884 PMCID: PMC9076696 DOI: 10.1039/c9ra09705h] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 12/16/2019] [Indexed: 12/27/2022] Open
Abstract
The extensive use of chlorobenzene in chemical, pharmaceutical, and agrochemical industries poses a severe health hazard to human beings, because it is highly toxic. The detection of chlorobenzene by metal oxide gas sensors is difficult, owing to its chemically inert molecular structure. In this study, well-dispersed Pd nanoparticles were deposited on porous ZnO nanoplates via surface ion exchange, followed by H2 reduction. The preparation process effectively prevented the aggregation and uncontrollable growth of Pd particles. A gas-sensing test was conducted, and the modification of size-controlled Pd nanoparticles was found to effectively enhance the sensing properties of porous ZnO nanoplates to chlorobenzene over 300 °C (higher sensitivity at a low operating temperature). At 440 °C, 5% Pd@ZnO sensor showed a drastic increase in response by nearly 4.5-fold, as well as excellent sensing selectivity to chlorobenzene. Its repeatability and stability were acceptable. As known, Pd nanocatalysts contribute to the oxidation of chlorinated aromatic compounds. Pd@ZnO sensors generated more catalytic sites and oxygen species (confirmed by XPS), thus enhancing chlorobenzene oxidation and improving the sensitivity of ZnO-based gas sensors. Well-dispersed and size-controlled Pd nanocatalysts were deposited on porous ZnO nanoplates via surface ion exchange for enhanced and selective chlorobenzene-sensor.![]()
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Affiliation(s)
- Zhenyu Feng
- Key Laboratory for Colloid and Interface Chemistry of Education Ministry
- School of Chemistry and Chemical Engineering
- Shandong University
- Jinan
- P. R. China
| | - Cuiling Gao
- Shandong Institute for Product Quality Inspection
- Jinan
- P. R. China
| | - Xicheng Ma
- Key Laboratory for Colloid and Interface Chemistry of Education Ministry
- School of Chemistry and Chemical Engineering
- Shandong University
- Jinan
- P. R. China
| | - Jinhua Zhan
- Key Laboratory for Colloid and Interface Chemistry of Education Ministry
- School of Chemistry and Chemical Engineering
- Shandong University
- Jinan
- P. R. China
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17
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Abstract
In this work, the activity of bimetallic Pd-Au doped hierarchically structured titania catalysts has been investigated in the total oxidation of toluene. In earlier works, doping titania with group Vb metal oxides ensured an increased catalytic performance in the elimination of VOC molecules. A synergy between gold and palladium loaded at the surface of titania supports provided better performances in VOC oxidation reactions. Therefore, the main focus in this work was to investigate the durability of the prepared catalysts under long time-on-stream periods. Vanadium-doped catalysts showed a stable activity throughout the whole 110 h test, whereas, surprisingly, niobium-doped catalysts presented a cycle-like activity while nevertheless maintaining a high performance in toluene elimination. Operando Diffuse Reflectance Infrared Fourrier Transform spectroscopy (DRIFT) experiments revealed that variations in the presence of OH radicals and the presence of carbonaceous compounds adsorbed at the surface of spent catalysts varies with the occurrence of oscillations. X-ray Photoelectron Spectroscopy (XPS) results show that interactions between the material and the active phase provided extra amounts of mobile oxygen species and participated in easing the reduction of palladium. An enhanced redox reaction scheme is thus obtained and allows the occurrence of the cyclic-like performance of the catalyst.
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18
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Aznárez A, Delaigle R, Eloy P, Gaigneaux E, Korili S, Gil A. Catalysts based on pillared clays for the oxidation of chlorobenzene. Catal Today 2015. [DOI: 10.1016/j.cattod.2014.07.024] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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19
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Barakat T, Rooke JC, Cousin R, Lamonier JF, Giraudon JM, Su BL, Siffert S. Investigation of the elimination of VOC mixtures over a Pd-loaded V-doped TiO2 support. NEW J CHEM 2014. [DOI: 10.1039/c3nj01190a] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Mixing butanone and toluene enhances their elimination over a Pd/5%V-TiO2 catalyst and reduces the formation of toxic reaction by-products.
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Affiliation(s)
- T. Barakat
- Unité de Chimie Environnementale et Interactions sur le Vivant E.A.4492
- Université du Littoral Côte d'Opale
- 59140 Dunkerque, France
| | - J. C. Rooke
- Laboratory of Inorganic Materials Chemistry
- University of Namur
- 5000 Namur, Belgium
| | - R. Cousin
- Unité de Chimie Environnementale et Interactions sur le Vivant E.A.4492
- Université du Littoral Côte d'Opale
- 59140 Dunkerque, France
| | - J.-F. Lamonier
- Unité de Catalyse et Chimie du Solide UMR CNRS 8181
- Université Lille 1
- 59655 Villeneuve d'Ascq, France
| | - J.-M. Giraudon
- Unité de Catalyse et Chimie du Solide UMR CNRS 8181
- Université Lille 1
- 59655 Villeneuve d'Ascq, France
| | - B.-L. Su
- Laboratory of Inorganic Materials Chemistry
- University of Namur
- 5000 Namur, Belgium
| | - S. Siffert
- Unité de Chimie Environnementale et Interactions sur le Vivant E.A.4492
- Université du Littoral Côte d'Opale
- 59140 Dunkerque, France
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20
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LI X, SUN M, ROOKE JC, CHEN L, SU BL. Synthesis and applications of hierarchically porous catalysts. CHINESE JOURNAL OF CATALYSIS 2013. [DOI: 10.1016/s1872-2067(11)60507-x] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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21
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Parlett CMA, Wilson K, Lee AF. Hierarchical porous materials: catalytic applications. Chem Soc Rev 2013; 42:3876-93. [DOI: 10.1039/c2cs35378d] [Citation(s) in RCA: 764] [Impact Index Per Article: 69.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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22
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Finol MF, Rooke J, Su BL, Trentesaux M, Giraudon JM, Lamonier JF. Additional effects of Pt and Nb on hierarchically porous titania in the catalytic removal of n-butanol. Catal Today 2012. [DOI: 10.1016/j.cattod.2011.11.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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23
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Barakat T, Rooke JC, Franco M, Cousin R, Lamonier JF, Giraudon JM, Su BL, Siffert S. Pd- and/or Au-Loaded Nb- and V-Doped Macro-Mesoporous TiO2 Supports as Catalysts for the Total Oxidation of VOCs. Eur J Inorg Chem 2012. [DOI: 10.1002/ejic.201101233] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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24
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Abstract
The catalytic performance of a commercial TiO2 was investigated towards the total oxidation of toluene. A variety of two titania supports was used in this work, shaped (pellets) and non-shaped (powder) materials. 0.5wt% Pd or Pt were impregnated onto both types of titania supports using the wet impregnation method. A decrease in the surface area of the obtained catalysts was noticed after the catalytic test, although it was still much higher than that of classical titania supports. The catalysts were tested in the total oxidation of toluene, and a major decrease in activity was noticed for Pt impregnated “shaped” supports.
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Lamonier JF, Nguyen T, Franco M, Siffert S, Cousin R, Li Y, Yang X, Su BL, Giraudon JM. Influence of the meso-macroporous ZrO2–TiO2 calcination temperature on the pre-reduced Pd/ZrO2–TiO2 (1/1) performances in chlorobenzene total oxidation. Catal Today 2011. [DOI: 10.1016/j.cattod.2010.11.048] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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26
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Lemaire A, Rooke JC, Chen LH, Su BL. Direct observation of macrostructure formation of hierarchically structured meso-macroporous aluminosilicates with 3D interconnectivity by optical microscope. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:3030-3043. [PMID: 21275420 DOI: 10.1021/la104679h] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Hierarchically structured spongy meso-macroporous aluminosilicates with high tetrahedral aluminum content were synthesized from a mixture of single molecular alkoxide precursor, (sec-BuO)2-Al-O-Si(OEt)3, already containing Si-O-Al bonds, and a silica coreactant, tetramethoxysilane (TMOS). The spontaneous byproduct templated macroporous structure formation has been directly visualized using in situ high-resolution optical microscopy (OM), allowing the crucial observation of a microbubble dispersion which is directly correlated to the macrostructure observed by electronic microscopies (SEM and TEM). This discovery leads to a comparative study with meso-macroporous pure metal oxide and to a proposal of the formation mechanism of meso-macroporous aluminosilicates with 3D interconnectivity. The aluminosilicate phase/microbubbles emulsion is produced by a phase separation process occurring between the aluminosilicate nanoparticles and the liquid hydrolysis-condensation reaction byproducts (water, methanol, ethanol, and butanol). The use of alkoxysilane improves the heterocondensation rates between the highly reactive aluminum alkoxide part of the single precursor and added silica species but, above all, leads to the spontaneous generation of an unusual meso-macroporosity in alkaline media. The particles obtained at pH = 13.0 featured regular micrometer-sized macrospheres separated by very thin mesoporous walls and connected by submicrometric openings, providing a 3D interconnectivity. The slight increase in pH value to 13.5 induced significant modifications in morphology and textural properties due to the slower gelification process of the aluminosilicate phase, resulting in the formation of an aluminosilicate material constituted of 1-2 µm large independent hollow mesoporous spheres.
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Affiliation(s)
- Arnaud Lemaire
- Laboratory of Inorganic Materials Chemistry (CMI), University of Namur (FUNDP), 61 rue de Bruxelles, 5000 Namur, Belgium
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27
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Doggali P, Kusaba H, Einaga H, Bensaid S, Rayalu S, Teraoka Y, Labhsetwar N. Low-cost catalysts for the control of indoor CO and PM emissions from solid fuel combustion. JOURNAL OF HAZARDOUS MATERIALS 2011; 186:796-804. [PMID: 21163572 DOI: 10.1016/j.jhazmat.2010.11.072] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2010] [Revised: 10/16/2010] [Accepted: 11/17/2010] [Indexed: 05/30/2023]
Abstract
Cu-Mn based mixed oxide type low-cost catalysts have been prepared in supported form using mesoporous Al(2)O(3), TiO(2) and ZrO(2) supports. These supports have been prepared by templating method using a natural biopolymer, chitosan. The synthesized catalysts have been characterized by XRD, BET-SA, SEM, O(2)-TPD and TG investigations. The catalytic activity for CO as well as PM oxidation was studied, in a view of their possible applications in the control of emissions from solid fuel combustion of rural cook-stoves. The trend observed for the catalytic activity of the synthesized catalysts for CO oxidation was ZrO(2)>TiO(2)>Al(2)O(3) while for PM oxidation it was observed to be TiO(2)>ZrO(2)>Al(2)O(3). The effect of CO(2), SO(2) and H(2)O on CO oxidation activity was also investigated, and despite partial deactivation, the catalysts show good CO oxidation activity. An effective regeneration treatment was attempted by heating the partially deactivated catalysts in presence of oxygen. Redox properties of TiO(2) and ZrO(2) and their structure appeared to be responsible for their promotional activity for CO and PM oxidation reactions. These unordered mesoporous materials could be useful for such reactions where mass transfer is more important than shape and size selectivity.
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Affiliation(s)
- Pradeep Doggali
- Environmental Material Division, National Environmental Engineering Research Institute (NEERI-CSIR), Nehru Marg, Nagpur, India
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28
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Yang XY, Léonard A, Lemaire A, Tian G, Su BL. Self-formation phenomenon to hierarchically structured porous materials: design, synthesis, formation mechanism and applications. Chem Commun (Camb) 2011; 47:2763-86. [DOI: 10.1039/c0cc03734f] [Citation(s) in RCA: 169] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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29
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Hierarchically structured functional materials: Synthesis strategies for multimodal porous networks. PURE APPL CHEM 2009. [DOI: 10.1351/pac-con-09-05-06] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Hierarchically porous materials displaying multimodal pore sizes are desirable for their improved flow performance coupled with high surface areas. In the last five years, a tremendous amount of research has focused upon the synthesis and applications of hierarchically porous materials. This review aims to open up a new avenue of research in this exciting field. At first, recent progress in the synthesis of hierarchically porous materials, targeted through templating methods, is reviewed. These synthesis methods involve a supermolecular assembly of amphiphilic polymers or surfactants combined with second surfactant systems or with macrotemplates such as solid particles, liquid drops, and air bubbles. The preparation procedures using surfactants combined with other chemical or physical methods, controlled phase-separation, or template replication will also be discussed. Subsequently, an innovative procedure concerning the self-formation of hierarchically porous materials is thoroughly examined. This self-formation procedure is based on a self-generated porogen mechanism. Porogens such as alcohol molecules can be precisely controlled at the molecular level to design new hierarchically porous materials. Most of these synthesis methods allow an easy and independent adjustment to the multiporosity of a material, i.e., its micro-, meso-, and macroporosity.
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