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Selective Oxidation of Alcohols and Alkenes with Molecular Oxygen Catalyzed by Highly Dispersed Cobalt (II) Decorated 12-Tungstosilicic Acid-Modified Zirconia. Catalysts 2022. [DOI: 10.3390/catal12121622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Traditional procedures for oxidation processes suffer from a lack of selectivity, the use of organic solvents, the toxicity of the reagents, and waste production. As a cleaner alternative, highly dispersed Co over 12-tungstosilicicacid modified zirconia was synthesized and used for the selective oxidation of benzyl alcohol and styrene with molecular oxygen to carbonyl compounds under environmentally benign solvent-free conditions. The supremacy of the present catalyst lies in achieving excellent selectivity (>90%) for products with a very high turnover number. The catalytic activity of the recycled catalysts was also explored under optimized conditions to confirm sustainability. Further, the viability of the catalyst was studied via oxidation of various alcohols and alkenes under optimized conditions as well as superiority by comparison with the reported catalysts.
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Najafishirtari S, Friedel Ortega K, Douthwaite M, Pattisson S, Hutchings GJ, Bondue CJ, Tschulik K, Waffel D, Peng B, Deitermann M, Busser GW, Muhler M, Behrens M. A Perspective on Heterogeneous Catalysts for the Selective Oxidation of Alcohols. Chemistry 2021; 27:16809-16833. [PMID: 34596294 PMCID: PMC9292687 DOI: 10.1002/chem.202102868] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Indexed: 01/15/2023]
Abstract
Selective oxidation of higher alcohols using heterogeneous catalysts is an important reaction in the synthesis of fine chemicals with added value. Though the process for primary alcohol oxidation is industrially established, there is still a lack of fundamental understanding considering the complexity of the catalysts and their dynamics under reaction conditions, especially when higher alcohols and liquid‐phase reaction media are involved. Additionally, new materials should be developed offering higher activity, selectivity, and stability. This can be achieved by unraveling the structure–performance correlations of these catalysts under reaction conditions. In this regard, researchers are encouraged to develop more advanced characterization techniques to address the complex interplay between the solid surface, the dissolved reactants, and the solvent. In this mini‐review, we report some of the most important approaches taken in the field and give a perspective on how to tackle the complex challenges for different approaches in alcohol oxidation while providing insight into the remaining challenges.
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Affiliation(s)
- Sharif Najafishirtari
- Faculty of Chemistry and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Carl-Benz-Straße 199, 47057, Duisburg, Germany
| | - Klaus Friedel Ortega
- Institute of Inorganic Chemistry, Kiel University, Max-Eyth-Straße 2, 24118, Kiel, Germany
| | - Mark Douthwaite
- Cardiff Catalysis Institute, Cardiff University, CF10 3AT, Cardiff, United Kingdom
| | - Samuel Pattisson
- Cardiff Catalysis Institute, Cardiff University, CF10 3AT, Cardiff, United Kingdom
| | - Graham J Hutchings
- Cardiff Catalysis Institute, Cardiff University, CF10 3AT, Cardiff, United Kingdom
| | - Christoph J Bondue
- Faculty of Chemistry and Biochemistry, Lab. of Electrochemistry & Nanoscale Materials, Ruhr-University Bochum, Universitätsstraße. 150, ZEMOS 1.41, 44780, Bochum, Germany
| | - Kristina Tschulik
- Faculty of Chemistry and Biochemistry, Lab. of Electrochemistry & Nanoscale Materials, Ruhr-University Bochum, Universitätsstraße. 150, ZEMOS 1.41, 44780, Bochum, Germany
| | - Daniel Waffel
- Faculty of Chemistry and Biochemistry, Lab. of Industrial Chemistry, Ruhr-University Bochum, Universitätsstraße 150, NBCF 04 / 690, 44780, Bochum, Germany
| | - Baoxiang Peng
- Faculty of Chemistry and Biochemistry, Lab. of Industrial Chemistry, Ruhr-University Bochum, Universitätsstraße 150, NBCF 04 / 690, 44780, Bochum, Germany
| | - Michel Deitermann
- Faculty of Chemistry and Biochemistry, Lab. of Industrial Chemistry, Ruhr-University Bochum, Universitätsstraße 150, NBCF 04 / 690, 44780, Bochum, Germany
| | - G Wilma Busser
- Faculty of Chemistry and Biochemistry, Lab. of Industrial Chemistry, Ruhr-University Bochum, Universitätsstraße 150, NBCF 04 / 690, 44780, Bochum, Germany
| | - Martin Muhler
- Faculty of Chemistry and Biochemistry, Lab. of Industrial Chemistry, Ruhr-University Bochum, Universitätsstraße 150, NBCF 04 / 690, 44780, Bochum, Germany
| | - Malte Behrens
- Faculty of Chemistry and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Carl-Benz-Straße 199, 47057, Duisburg, Germany.,Institute of Inorganic Chemistry, Kiel University, Max-Eyth-Straße 2, 24118, Kiel, Germany
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Bakhtiarzadeh Z, Rouhani S, Karimi Z, Rostamnia S, Msagati TA, Kim D, Jang HW, Ramakrishna S, Varma RS, Shokouhimehr M. Hydrothermal self - sacrificing growth of polymorphous MnO2 on magnetic porous - carbon (Fe3O4@Cg/MnO2): A sustainable nanostructured catalyst for activation of molecular oxygen. MOLECULAR CATALYSIS 2021. [DOI: 10.1016/j.mcat.2021.111603] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Roy KS, Subramaniam C, Panchakarla LS. Non-Stoichiometry Induced Exsolution of Metal Oxide Nanoparticles via Formation of Wavy Surfaces and their Enhanced Electrocatalytic Activity: Case of Misfit Calcium Cobalt Oxide. ACS APPLIED MATERIALS & INTERFACES 2021; 13:9897-9907. [PMID: 33591175 DOI: 10.1021/acsami.0c20891] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Most heterogeneous catalytic reactions demand high density and yet spatially separated nanoparticles that are strongly anchored on the oxide surfaces. Such nanoparticles can be deposited or synthesized in situ via nonstoichiometric methods. To date, nanoparticles have been exsolved from perovskite oxide surfaces using nonstoichiometric processes. However, the density of the space-separated nanoparticles on the oxide surfaces is still low. And less attention is paid toward the changes that happen to the host during the nanoparticle exsolution process. In this work, we demonstrated in situ exsolution of ultrafine nanoparticles (∼5 nm) of either Co3O4 or Ca(OH)2 via judicious control of nonstoichiometry in a misfit Ca3Co4O9 (CCO). The nanoparticle density over the CCO surface reached as high as 8500/μm2, which is significantly higher than previously reported values. High-resolution electron microscopy studies reveal the formation mechanism of Co3O4 nanoparticles over CCO, and the formation takes palace via the formation of wavy surfaces on the CCO. Defects caused by the nonstoichiometric synthesis created microstrain within the host CCO, resulting in making the new density of states near the Fermi energy. Further, the exsolution process turned the inert host (CCO) into electrocatalytically active toward water splitting. The nonstoichiometric samples obtained by shorter annealing times showed high electrocatalytic behavior for the hydrogen evolution (HER) and oxygen evolution (OER) reactions. The catalytic activity is further enhanced (reaching overpotential of 320 mV and 410 mV for HER and OER respectively, for a current density of 10 mA/cm2) by removing the surface nanoparticles. The observation indicates that the active sites that are produced during the nonstoichiometric synthesis also present in the bulk of the CCO (host). We believe that similar nonstoichiometric synthesis can be applied to a wide variety of tricomponent systems, and they could endow the hosts with novel properties for applications such as catalysis and thermoelectrics.
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Affiliation(s)
- Kankona Singha Roy
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
| | | | - Leela S Panchakarla
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
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Synthesis and Characterization of CoxOy–MnCO3 and CoxOy–Mn2O3 Catalysts: A Comparative Catalytic Assessment Towards the Aerial Oxidation of Various Kinds of Alcohols. Processes (Basel) 2020. [DOI: 10.3390/pr8080910] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
CoxOy–manganese carbonate (X%)(CoxOy–MnCO3 catalysts (X = 1–7)) were synthesized via a straightforward co-precipitation strategy followed by calcination at 300 °C. Upon calcination at 500 °C, these were transformed to CoxOy–dimanganese trioxide i.e., (X%)CoxOy–Mn2O3. A relative catalytic evaluation was conducted to compare the catalytic efficiency of the two prepared catalysts for aerial oxidation of benzyl alcohol (BzOH) to benzaldehyde (BzH) using O2 molecule as a clean oxidant without utilizing any additives or alkalis. Amongst the different percentages of doping with CoxOy (0–7% wt./wt.) on MnCO3 support, the (1%)CoxOy–MnCO3 catalyst exhibited the highest catalytic activity. The influence of catalyst loading, calcination temperature, reaction time, and temperature and catalyst dosage was thoroughly assessed to find the optimum conditions of oxidation of benzyl alcohol (BzOH) for getting the highest catalytic efficiency. The (1%)CoxOy–MnCO3 catalyst which calcined at 300 °C displayed the best effectiveness and possessed the largest specific surface area i.e., 108.4 m2/g, which suggested that the calcination process and specific surface area play a vital role in this transformation. A 100% conversion of BzOH along with BzH selectivity >99% was achieved after just 20 min. Notably, the attained specific activity was found to be considerably larger than the previously-reported cobalt-containing catalysts for this transformation. The scope of this oxidation reaction was expanded to various alcohols containing aromatic, aliphatic, allylic, and heterocyclic alcohols without any further oxidation i.e., carboxylic acid formation. The scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and Brunauer–Emmett–Teller (BET) specific surface area analytical techniques were used to characterize the prepared catalysts. The obtained catalyst could be easily regenerated and reused for six consecutive runs without substantial decline in its efficiency.
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