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Catalysts, Volume 7, Issue 4 (April 2017)

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Cover Story The increasing demand for highly efficient, visible-light-active photocatalysts can be addressed by [...] Read more.
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Open AccessArticle Total Oxidation of Propane Using CeO2 and CuO-CeO2 Catalysts Prepared Using Templates of Different Nature
Catalysts 2017, 7(4), 96; doi:10.3390/catal7040096
Received: 16 January 2017 / Revised: 7 March 2017 / Accepted: 17 March 2017 / Published: 23 March 2017
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Abstract
Several CeO2 and CuO-CeO2 catalysts were prepared using different methods, i.e., a homogeneous precipitation with urea, a nanocasting route using CMK-3 carbon as a hard template and a sol–gel process using Poly(methyl methacrylate) (PMMA) polymer as a soft template, and tested
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Several CeO2 and CuO-CeO2 catalysts were prepared using different methods, i.e., a homogeneous precipitation with urea, a nanocasting route using CMK-3 carbon as a hard template and a sol–gel process using Poly(methyl methacrylate) (PMMA) polymer as a soft template, and tested in the total oxidation of propane. The catalysts were characterized by a number of physicochemical techniques (XRD, N2 adsorption, TPR, XPS, Raman spectroscopy) showing distinct characteristics. For each series, Cu-Ce-O catalysts with low Cu-loadings (5 wt % CuO) showed the highest activity, higher than those samples either without copper or with high Cu-loading (13 wt % CuO). The incorporation of copper leads to an increase of the concentration of bulk defects but if the Cu-loading is too high the surface area drastically falls. The highest activity in the total oxidation of propane was achieved by Cu-containing ceria catalysts synthesized using a polymer as a template, as this method yields high surface area materials. The surface area and the number of bulk/sub-surface defects of the ceria seem to be the main properties determining the catalytic activity. Full article
(This article belongs to the Special Issue Ceria-based Catalysts)
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Open AccessArticle Three-Dimensional TiO2 Structures Incorporated with Tungsten Oxide for Treatment of Toxic Aromatic Volatile Compounds
Catalysts 2017, 7(4), 97; doi:10.3390/catal7040097
Received: 24 February 2017 / Revised: 16 March 2017 / Accepted: 20 March 2017 / Published: 23 March 2017
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Abstract
This study assessed 3D WO3–TiO2 nanoflowers (WTNF) synthesized by a combined hydrothermal–ultrasonication–impregnation method for their applicability to the treatment of aromatic volatile compounds under visible-light illumination. The scanning electron microscopy exhibited the formation of 3D structures in the prepared WTNF
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This study assessed 3D WO3–TiO2 nanoflowers (WTNF) synthesized by a combined hydrothermal–ultrasonication–impregnation method for their applicability to the treatment of aromatic volatile compounds under visible-light illumination. The scanning electron microscopy exhibited the formation of 3D structures in the prepared WTNF samples. The X-ray diffraction patterns and energy dispersive X-ray results indicated a successful incorporation of WO3 into TNF structures. The UV-visible spectroscopy showed that the prepared WTNF samples can be functioned under visible light irradiation. The output-to-input concentration ratios of toluene and o-xylene with WTNF samples were lower than those of TiO2 nanoflowers. These findings were illustrated on the basis of charge separation ability, adsorption capability, and light absorption of the sample photocatalysts. The input-to-output concentration ratios of the target chemicals were lowest for 10 M NaOH and highest for 5 M NaOH. The photocatalytic degradation efficiencies of WTNF sample photocatalysts increased with increasing WO3 content from 0.1% to 1.0%, and dropped gradually with increasing WO3 content further to 4.0%. Light-emitting-diodes (LEDs) are a more highly energy-efficient light source compared to a conventional lamp for the photocatalytic degradation of toluene and o-xylene, although the photocatalytic activity is higher for the conventional lamp. Full article
(This article belongs to the Special Issue Heterogeneous Catalysis for Environmental Remediation)
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Open AccessArticle Fivefold Enhanced Photoelectrochemical Properties of ZnO Nanowire Arrays Modified with C3N4 Quantum Dots
Catalysts 2017, 7(4), 99; doi:10.3390/catal7040099
Received: 17 December 2016 / Revised: 7 March 2017 / Accepted: 20 March 2017 / Published: 24 March 2017
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Abstract
A facile and effective growing strategy of graphite-like carbon nitride quantum dots (CNQDs) modified on ZnO nanowire array composite electrodes has been successfully designed and prepared for the first time. The remarkable quantum enhanced properties were carefully studied by means of scanning electron
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A facile and effective growing strategy of graphite-like carbon nitride quantum dots (CNQDs) modified on ZnO nanowire array composite electrodes has been successfully designed and prepared for the first time. The remarkable quantum enhanced properties were carefully studied by means of scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscope (XPS), UV-vis diffuse reflectance, PEC performance, and photocatalytic hydrogen production, and the results were in good agreement. Fivefold enhanced photoelectrochemical performances of this novel hierarchical hetero-array prepared in this paper compared with pure ZnO nanowire arrays were obtained under UV-light. The effect was attributed to the remarkable charge separation between CNQDs and ZnO nanowire arrays. Additional investigations revealed that the particular structure of CNQDs/ZnO composites contributed to the separation of a photon-generation carrier and an enhanced photoelectric current. Moreover, the absorption edge of CNQD-modified ZnO nanowire arrays was slightly broadened, and the diameter was reduced as well. The photoelectrochemistry hydrogen evolution splitting water using simulated solar irradiation exhibited the foreground of a possible application of a mechanism of photoelectrochemistry hydrogen evolution over CNQDs/ZnO composite electrodes. Full article
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Open AccessArticle High Catalytic Activity of Heterometallic (Fe6Na7 and Fe6Na6) Cage Silsesquioxanes in Oxidations with Peroxides
Catalysts 2017, 7(4), 101; doi:10.3390/catal7040101
Received: 16 February 2017 / Revised: 17 March 2017 / Accepted: 21 March 2017 / Published: 27 March 2017
Cited by 5 | PDF Full-text (5775 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Two types of heterometallic (Fe(III),Na) silsesquioxanes—[Ph5Si5O10]2[Ph10Si10O21]Fe6(O2‒)2Na7(H3O+)(MeOH)2(MeCN)4.5.1.25(MeCN), I, and [Ph5Si5
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Two types of heterometallic (Fe(III),Na) silsesquioxanes—[Ph5Si5O10]2[Ph10Si10O21]Fe6(O2‒)2Na7(H3O+)(MeOH)2(MeCN)4.5.1.25(MeCN), I, and [Ph5Si5O10]2[Ph4Si4O8]2Fe6Na6(O2‒)3(MeCN)8.5(H2O)8.44, II—were obtained and characterized. X-ray studies established distinctive structures of both products, with pair of Fe(III)-O-based triangles surrounded by siloxanolate ligands, giving fascinating cage architectures. Complex II proved to be catalytically active in the formation of amides from alcohols and amines, and thus becoming a rare example of metallasilsesquioxanes performing homogeneous catalysis. Benzene, cyclohexane, and other alkanes, as well as alcohols, can be oxidized in acetonitrile solution to phenol—the corresponding alkyl hydroperoxides and ketones, respectively—by hydrogen peroxide in air in the presence of catalytic amounts of complex II and trifluoroacetic acid. Thus, the cyclohexane oxidation at 20 °C gave oxygenates in very high yield of alkanes (48% based on alkane). The kinetic behaviour of the system indicates that the mechanism includes the formation of hydroxyl radicals generated from hydrogen peroxide in its interaction with di-iron species. The latter are formed via monomerization of starting hexairon complex with further dimerization of the monomers. Full article
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Open AccessArticle Caprolactam-Based Brønsted Acidic Ionic Liquids for Biodiesel Production from Jatropha Oil
Catalysts 2017, 7(4), 102; doi:10.3390/catal7040102
Received: 21 February 2017 / Revised: 20 March 2017 / Accepted: 23 March 2017 / Published: 27 March 2017
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Abstract
Caprolactam-based ionic liquids show many advantages, such as the lower toxicity, lower cost, and a simple preparation process. In this work, caprolactam-based ionic liquids were prepared and adopted as catalysts for the transesterification of Jatropha oil with methanol. The results demonstrated that the
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Caprolactam-based ionic liquids show many advantages, such as the lower toxicity, lower cost, and a simple preparation process. In this work, caprolactam-based ionic liquids were prepared and adopted as catalysts for the transesterification of Jatropha oil with methanol. The results demonstrated that the SO3H-functional caprolactam‐based ionic liquids have higher catalytic activity than those of the caprolactam-based ionic liquids without sulfonic group or the SO3H-functional pyridine-based ionic liquids, attributed to their stronger Brønsted acidity. By optimizing the reaction parameter, the biodiesel yield catalyzed by 1-(4-sulfonic group) butylcaprolactamium hydrogen sulfate ([HSO3-bCPL][HSO4]) could reach above 95% at 140 °C for 3 h. Furthermore, the ionic liquid had a good reusability. Full article
(This article belongs to the Special Issue Organocatalysis in Ionic Liquids)
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Open AccessArticle Dicyclopentadiene Hydroformylation to Value-Added Fine Chemicals over Magnetically Separable Fe3O4-Supported Co-Rh Bimetallic Catalysts: Effects of Cobalt Loading
Catalysts 2017, 7(4), 103; doi:10.3390/catal7040103
Received: 12 January 2017 / Revised: 22 February 2017 / Accepted: 14 March 2017 / Published: 30 March 2017
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Abstract
Six Co-Rh/Fe3O4 catalysts with different cobalt loadings were prepared by the co-precipitation of RhCl3, Co(NO3)2, and Fe(NO3)3 using Na2CO3 as the precipitant. These catalysts were tested for dicyclopentadiene
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Six Co-Rh/Fe3O4 catalysts with different cobalt loadings were prepared by the co-precipitation of RhCl3, Co(NO3)2, and Fe(NO3)3 using Na2CO3 as the precipitant. These catalysts were tested for dicyclopentadiene (DCPD) hydroformylation to monoformyltricyclodecenes (MFTD) and diformyltricyclodecanes (DFTD). The results showed that the MFTD formation rate increased with increasing cobalt loading, whereas the DFTD formation rate initially increased and then decreased when the cobalt loading was greater than twice that of Rh. The DFTD selectivity was only 21.3% when monometallic Rh/Fe3O4 was used as the catalyst. In contrast, the selectivity was 90.6% at a similar DCPD conversion when the bimetallic 4Co-2Rh/Fe3O4 catalyst was employed. These catalysts were characterized by temperature-programmed reduction (TPR), temperature-programmed desorption (TPD), and thermogravimetric and differential thermal analyses (TG-DTA). The results obtained by these complimentary characterization techniques indicated that adding cobalt to the Rh/Fe3O4 catalyst enhanced the Rh reducibility and dispersion; the Rh reducibility was easily altered, and increasing the cobalt loading improved the Rh dispersion. It was concluded that the enhanced catalytic performance with increasing cobalt loading might be due to the formation of a more reactive Rh species with a different Rh–phosphine interaction strength on the catalyst surface. Full article
(This article belongs to the Special Issue Magnetic Nanocatalysts)
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Open AccessArticle Methanation of Carbon Dioxide over Ni–Ce–Zr Oxides Prepared by One-Pot Hydrolysis of Metal Nitrates with Ammonium Carbonate
Catalysts 2017, 7(4), 104; doi:10.3390/catal7040104
Received: 6 March 2017 / Revised: 28 March 2017 / Accepted: 29 March 2017 / Published: 31 March 2017
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Abstract
Ni–Ce–Zr mixed oxides were prepared through one-pot hydrolysis of mixed metal nitrates with ammonium carbonate for CO2 methanation. The effects of Ce/Zr molar ratio and Ni content on catalysts’ physical and chemical properties, reduction degree of Ni2+, and catalytic properties
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Ni–Ce–Zr mixed oxides were prepared through one-pot hydrolysis of mixed metal nitrates with ammonium carbonate for CO2 methanation. The effects of Ce/Zr molar ratio and Ni content on catalysts’ physical and chemical properties, reduction degree of Ni2+, and catalytic properties were systematically investigated. The results showed that Zr could lower metallic Ni particle sizes and alter interaction between Ni and supports, resulting in enhancements in the catalytic activity for CO2 methanation. The Ni–Ce–Zr catalyst containing 40 wt % Ni and Ce/Zr molar ratio of 9:1 exhibited the optimal catalytic properties, with 96.2% CO2 conversion and almost 100% CH4 selectivity at a low temperature of 275 °C. During the tested period of 500 h, CO2 conversion and CH4 selectivity over Ni–Ce–Zr catalyst kept constant under 300 °C. Full article
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Open AccessArticle Environmental Benign Synthesis of Lithium Silicates and Mg-Al Layered Double Hydroxide from Vermiculite Mineral for CO2 Capture
Catalysts 2017, 7(4), 105; doi:10.3390/catal7040105
Received: 26 February 2017 / Revised: 20 March 2017 / Accepted: 31 March 2017 / Published: 3 April 2017
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Abstract
This research introduces a completely new environmental benign synthesis route for obtaining two kinds of inter-mediate and high temperature CO2 sorbents, Mg-Al layered double hydroxide (LDH) and Li4SiO4, from vermiculite. The mineral vermiculite was leached with acid, from
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This research introduces a completely new environmental benign synthesis route for obtaining two kinds of inter-mediate and high temperature CO2 sorbents, Mg-Al layered double hydroxide (LDH) and Li4SiO4, from vermiculite. The mineral vermiculite was leached with acid, from which the obtained SiO2 was used for the synthesis of Li4SiO4 and the leaching waste water was used for the synthesis of Mg-Al LDH. Therefore, no waste was produced during the whole process. Both Li4SiO4 and Mg-Al LDH sorbents were carefully characterized using XRD, SEM, and BET analyses. The CO2 capturing performance of these two sorbents was comprehensively evaluated. The influence of the Li/Si ratio, calcination temperature, calcination time, and sorption temperature on the CO2 sorption capacity of Li4SiO4, and the sorption temperature on the CO2 sorption capacity of LDH, were investigated. The optimal leaching acid concentration for vermiculite and the CO2 sorption/desorption cycling performance of both the Li4SiO4 and Mg-Al LDH sorbents were determined. In sum, this demonstrated a unique and environment-friendly scheme for obtaining two CO2 sorbents from cheap raw materials, and this idea is applicable to the efficient utilization of other minerals. Full article
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Open AccessArticle Thermal Activation of CuBTC MOF for CO Oxidation: The Effect of Activation Atmosphere
Catalysts 2017, 7(4), 106; doi:10.3390/catal7040106
Received: 24 February 2017 / Revised: 26 March 2017 / Accepted: 4 April 2017 / Published: 7 April 2017
Cited by 3 | PDF Full-text (4393 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
High performance catalysts for carbon monoxide (CO) oxidation were obtained through thermal activation of a CuBTC (BTC: 1,3,5-benzenetricarboxylic acid) metal–organic framework (MOF) in various atmospheres. X-ray diffraction (XRD), X-ray photonelectron spectroscopy (XPS), N2 adsorption–desorption measurement, and field emission scanning electron microscopy (FESEM)
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High performance catalysts for carbon monoxide (CO) oxidation were obtained through thermal activation of a CuBTC (BTC: 1,3,5-benzenetricarboxylic acid) metal–organic framework (MOF) in various atmospheres. X-ray diffraction (XRD), X-ray photonelectron spectroscopy (XPS), N2 adsorption–desorption measurement, and field emission scanning electron microscopy (FESEM) were adopted to characterize the catalysts. The results show that thermal activation by reductive H2 may greatly destroy the structure of CuBTC. Inert Ar gas has a weak influence on the structure of CuBTC. Therefore, these two catalysts exhibit low CO oxidation activity. Activating with O2 is effective for CuBTC catalysts, since active CuO species may be obtained due to the slight collapse of CuBTC structure. The highest activity is obtained when activating with CO reaction gas, since many pores and more effective Cu2O is formed during the thermal activation process. These results show that the structure and chemical state of coordinated metallic ions in MOFs are adjustable by controlling the activation conditions. This work provides an effective method for designing and fabricating high performance catalysts for CO oxidation based on MOFs. Full article
(This article belongs to the Special Issue Heterogeneous Catalysis for Environmental Remediation)
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Open AccessArticle Recyclable Polymer-Supported Terpyridine–Palladium Complex for the Tandem Aminocarbonylation of Aryl Iodides to Primary Amides in Water Using NaN3 as Ammonia Equivalent
Catalysts 2017, 7(4), 107; doi:10.3390/catal7040107
Received: 17 March 2017 / Revised: 3 April 2017 / Accepted: 5 April 2017 / Published: 7 April 2017
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Abstract
Primary aromatic amides are valuable compounds, which are generally prepared via Beckmann rearrangement of oximes and the hydration of nitriles in organic solvents. We investigated the environmentally friendly catalytic aminocarbonylation in water. Thus, a novel heterogeneous transition-metal catalyst, a polymer-supported terpyridine–palladium(II) complex, was
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Primary aromatic amides are valuable compounds, which are generally prepared via Beckmann rearrangement of oximes and the hydration of nitriles in organic solvents. We investigated the environmentally friendly catalytic aminocarbonylation in water. Thus, a novel heterogeneous transition-metal catalyst, a polymer-supported terpyridine–palladium(II) complex, was prepared and found to promote azidocarbonylation of aryl iodides with NaN3 and to reduce the generated benzoyl azides in water under CO gas to yield primary aryl amides with high to excellent yield in a one-pot reaction. The catalyst was recovered and reused several times with no loss of catalytic activity. Full article
(This article belongs to the Special Issue Organometallic Catalysis for Organic Synthesis)
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Open AccessArticle Efficient Hydrolysis of Lignocellulose by Acidic Ionic Liquids under Low-Toxic Condition to Microorganisms
Catalysts 2017, 7(4), 108; doi:10.3390/catal7040108
Received: 10 March 2017 / Revised: 4 April 2017 / Accepted: 6 April 2017 / Published: 7 April 2017
Cited by 1 | PDF Full-text (2372 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Lignocellulose is known as a renewable resource, and acidic ionic liquids have been highlighted as efficient catalysts for hydrolysis of cellulose. To achieve successive hydrolysis and fermentation, efficient hydrolysis with sufficiently diluted acidic ionic liquids is necessary because acidic ionic liquids are toxic
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Lignocellulose is known as a renewable resource, and acidic ionic liquids have been highlighted as efficient catalysts for hydrolysis of cellulose. To achieve successive hydrolysis and fermentation, efficient hydrolysis with sufficiently diluted acidic ionic liquids is necessary because acidic ionic liquids are toxic to fermentative microorganisms. Escherichia coli was confirmed to grow in 0.05 M dilute acidic ionic liquid—1-(1-butylsulfonic)-3-methylimidazolium hydrogen sulfate ([Sbmim][HSO4])—although the growth was suppressed in more concentrated solutions. Therefore, we applied the 0.05 M [Sbmim][HSO4] solution to hydrolysis of bagasse, leading to a glucose yield of 48% at 190 °C. This value is greater than that obtained with a concentrated [Sbmim][HSO4] solution, which is not suitable for the growth of Escherichia coli (yield: 40% in a 1.0 M solution). Efficient hydrolysis with acidic ionic liquids under low-toxic condition was achieved. Full article
(This article belongs to the Special Issue Catalysis in Innovative Solvents)
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Open AccessArticle Study of the V2O5-WO3/TiO2 Catalyst Synthesized from Waste Catalyst on Selective Catalytic Reduction of NOx by NH3
Catalysts 2017, 7(4), 110; doi:10.3390/catal7040110
Received: 1 December 2016 / Revised: 16 March 2017 / Accepted: 6 April 2017 / Published: 8 April 2017
Cited by 3 | PDF Full-text (1867 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
V2O5-WO3/TiO2 catalysts were synthesized from waste selective catalytic reduction (SCR) catalyst through oxalic acid leaching and impregnating with various V2O5 mass loadings. The denitration (deNOx) activity and physiochemical properties of the
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V2O5-WO3/TiO2 catalysts were synthesized from waste selective catalytic reduction (SCR) catalyst through oxalic acid leaching and impregnating with various V2O5 mass loadings. The denitration (deNOx) activity and physiochemical properties of the catalysts were investigated. All the catalysts were characterized by N2 adsorption/desorption, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and H2-temperature programmed reduction. The evaluation result revealed that the deNOx activity of newly synthesized catalyst with 1.0% V2O5 was almost recovered to the level of fresh catalyst, with NO conversion being recovered to 91% at 300 °C, and it also showed a good resistance to SO2 and H2O. The characterization results showed that the decrease of impurities, partial recovery of the V4+/V5+ ratio, and increased reducibility were mainly responsible for the recovery of catalytic activity. Full article
(This article belongs to the Special Issue Heterogeneous Catalysis for Environmental Remediation)
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Open AccessFeature PaperArticle Unprecedented Multifunctionality of Grubbs and Hoveyda–Grubbs Catalysts: Competitive Isomerization, Hydrogenation, Silylation and Metathesis Occurring in Solution and on Solid Phase
Catalysts 2017, 7(4), 111; doi:10.3390/catal7040111
Received: 28 February 2017 / Revised: 30 March 2017 / Accepted: 6 April 2017 / Published: 9 April 2017
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Abstract
This contribution showcases the interplay of several non-metathetic reactions (isomerization, silylation and “hydrogen-free” reduction) with metathesis in systems comprising a functionalized olefin and a soluble or resin-immobilized silane. These competing, one-pot reactions occur under activation by second-generation Ru-alkylidene catalysts. Different olefinic substrates were
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This contribution showcases the interplay of several non-metathetic reactions (isomerization, silylation and “hydrogen-free” reduction) with metathesis in systems comprising a functionalized olefin and a soluble or resin-immobilized silane. These competing, one-pot reactions occur under activation by second-generation Ru-alkylidene catalysts. Different olefinic substrates were used to study the influence of the substitution pattern on the reaction outcome. Emphasis is placed upon the rarely reported yet important transformations implying a solid phase-supported silane reagent. Catalytic species involved in and reaction pathways accounting for these concurrent processes are evidenced. An unexpected result of this research was the clearly proved partial binding of the olefin to the resin, thereby removing it from the reacting ensemble. Full article
(This article belongs to the Special Issue Ruthenium Catalysts)
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Open AccessArticle Steam Reforming of Bio-Compounds with Auto-Reduced Nickel Catalyst
Catalysts 2017, 7(4), 114; doi:10.3390/catal7040114
Received: 15 February 2017 / Revised: 31 March 2017 / Accepted: 31 March 2017 / Published: 13 April 2017
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Abstract
As an extension of chemical looping combustion, chemical looping steam reforming (CLSR) has been developed for H2 production. During CLSR, a steam reforming (SR) process occurs following the reduction of catalysts by the reforming feedstock itself (termed “auto-reduction”), as opposed to a separate,
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As an extension of chemical looping combustion, chemical looping steam reforming (CLSR) has been developed for H2 production. During CLSR, a steam reforming (SR) process occurs following the reduction of catalysts by the reforming feedstock itself (termed “auto-reduction”), as opposed to a separate, dedicated reducing agent like H2. This paper studied SR performances of four common bio-compounds (ethanol, acetone, furfural, and glucose) with a nickel catalyst that had undergone auto-reduction. A packed bed reactor was used to carry out the experiment of auto-reduction and subsequent SR. The effects of temperature and steam to carbon ratio (S/C) on the carbon conversions of the bio-compounds to gases and yields of gaseous products were investigated. The carbon deposition on spent catalysts was characterized by CHN elemental analysis and Scanning Electron Microscopy-Energy Dispersive X-ray Spectroscopy (SEM-EDX). The SR performance with the auto-reduced catalyst was close to that with the H2-reduced catalyst. In general, an increase in temperature or S/C would lead to an increase in H2 yields. The dependence of SR performance on temperature or S/C was specific to the type of bio-compounds. Accordingly, the main bottlenecks for SR of each bio-compound were summarized. A large amount of CH4 existed in the reforming product of ethanol. Severe carbon deposition was observed for SR of acetone at temperatures below 650 °C. A high thermal stability of furfural molecules or its derivatives restricted the SR of furfural. For SR of glucose, the main problem was the severe agglomeration of catalyst particles due to glucose coking. Full article
(This article belongs to the Special Issue Reforming Catalysts)
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Open AccessCommunication Lipase-Mediated Amidation of Anilines with 1,3-Diketones via C–C Bond Cleavage
Catalysts 2017, 7(4), 115; doi:10.3390/catal7040115
Received: 9 March 2017 / Revised: 10 April 2017 / Accepted: 12 April 2017 / Published: 14 April 2017
Cited by 1 | PDF Full-text (6938 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
In this work, an efficient and green lipase-mediated technique has been mined for the amidation of anilines with 1,3-diketones via C–C bond cleavage. Under the optimal conditions, high yields (64.3%–96.2%) could be obtained when Novozym 435 was used as the catalyst. Furthermore, Novozym
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In this work, an efficient and green lipase-mediated technique has been mined for the amidation of anilines with 1,3-diketones via C–C bond cleavage. Under the optimal conditions, high yields (64.3%–96.2%) could be obtained when Novozym 435 was used as the catalyst. Furthermore, Novozym 435 exhibited a satisfying reusability and more than 80% of yield can be obtained after seven cycles. This work provides a more rapid and mild strategy for amide synthesis with high yield and expands the application of enzyme in organic synthesis. Full article
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Open AccessArticle Hydrothermal Fabrication of High Specific Surface Area Mesoporous MgO with Excellent CO2 Adsorption Potential at Intermediate Temperatures
Catalysts 2017, 7(4), 116; doi:10.3390/catal7040116
Received: 5 March 2017 / Revised: 10 April 2017 / Accepted: 11 April 2017 / Published: 15 April 2017
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Abstract
In this work, we report on a novel sodium dodecyl sulfate (SDS)-assisted magnesium oxide (MgO)-based porous adsorbent synthesized by hydrothermal method for intermediate CO2 capture. For industrial MgO, its CO2 adsorption capacity is normally less than 0.06 mmol g−1,
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In this work, we report on a novel sodium dodecyl sulfate (SDS)-assisted magnesium oxide (MgO)-based porous adsorbent synthesized by hydrothermal method for intermediate CO2 capture. For industrial MgO, its CO2 adsorption capacity is normally less than 0.06 mmol g−1, with a specific surface area as low as 25.1 m2 g−1. Herein, leaf-like MgO nanosheets which exhibited a disordered layer structure were fabricated by the introduction of SDS surfactants and the control of other synthesis parameters. This leaf-like MgO adsorbent showed an excellent CO2 capacity of 0.96 mmol g−1 at moderate temperatures (~300 °C), which is more than ten times higher than that of the commercial light MgO. This novel mesoporous MgO adsorbent also exhibited high stability during multiple CO2 adsorption/desorption cycles. The excellent CO2 capturing performance was believed to be related to its high specific surface area of 321.3 m2 g−1 and abundant surface active adsorption sites. This work suggested a new synthesis scheme for MgO based CO2 adsorbents at intermediate temperatures, providing a competitive candidate for capturing CO2 from certain sorption enhanced hydrogen production processes. Full article
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Open AccessArticle Novel Synthesis of Plasmonic Ag/AgCl@TiO2 Continues Fibers with Enhanced Broadband Photocatalytic Performance
Catalysts 2017, 7(4), 117; doi:10.3390/catal7040117
Received: 28 February 2017 / Revised: 2 April 2017 / Accepted: 13 April 2017 / Published: 17 April 2017
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Abstract
The plasmonic Ag/AgCl@TiO2 fiber (S-CTF) photocatalyst was synthesized by a two-step approach, including the sol-gel and force spinning method for the preparation of TiO2 fibers (TF), and the impregnation-precipitation-photoreduction strategy for the deposition of Ag/AgCl onto the fibers. NaOH aqueous solution
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The plasmonic Ag/AgCl@TiO2 fiber (S-CTF) photocatalyst was synthesized by a two-step approach, including the sol-gel and force spinning method for the preparation of TiO2 fibers (TF), and the impregnation-precipitation-photoreduction strategy for the deposition of Ag/AgCl onto the fibers. NaOH aqueous solution was utilized to hydrolyze TiCl4, to synthesize TF and remove the byproduct HCl, and the produced NaCl was recycled for the formation and deposition of Ag/AgCl. The surface morphology, specific surface area, textural properties, crystal structure, elemental compositions and optical absorption of S-CTF were characterized by a series of instruments. These results revealed that the AgCl and Ag0 species were deposited onto TF successfully, and the obtained S-CTF showed improved visible light absorption due to the surface plasmon resonance of Ag0. In the photocatalytic degradation of X-3B, S-CTF exhibited significantly enhanced activities under separate visible or UV light irradiation, in comparison to TF. Full article
(This article belongs to the Special Issue Titanium Dioxide Photocatalysis)
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Open AccessArticle SO42−/Sn-MMT Solid Acid Catalyst for Xylose and Xylan Conversion into Furfural in the Biphasic System
Catalysts 2017, 7(4), 118; doi:10.3390/catal7040118
Received: 22 February 2017 / Revised: 1 April 2017 / Accepted: 11 April 2017 / Published: 17 April 2017
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Abstract
A sulphated tin ion-exchanged montmorillonite (SO42−/Sn-MMT) was successfully prepared by the ion exchange method of montmorillonite (MMT) with SnCl4, followed by the sulphation. This catalysis was applied as a solid acid catalyst for the heterogeneous catalytic transformations of
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A sulphated tin ion-exchanged montmorillonite (SO42−/Sn-MMT) was successfully prepared by the ion exchange method of montmorillonite (MMT) with SnCl4, followed by the sulphation. This catalysis was applied as a solid acid catalyst for the heterogeneous catalytic transformations of xylose and xylan into furfural in the bio-based 2-methyltetrahydrofuran/H2O biphasic system. These prepared catalysts were characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), temperature programmed desorption of ammonia (NH3-TPD), pyridine adsorbed Fourier transform infrared spectroscopy (Py-FTIR), element analysis (EA) and Brunauer-Emmett-Teller (BET) method. Their catalytic performance for xylose and xylan into furfural was also investigated. The reaction parameters such as the initial xylose and xylan concentration, the amounts of catalyst, the organic-to-aqueous phase volume ratio, the reaction temperature and time were studied to optimize the reaction conditions. Results displayed that SO42−/Sn-MMT contained both Brønsted acid and Lewis acid sites, and SO42− ions were contributive to the formation of stronger Brønsted acid sites, which could improve the reaction efficiency. Reaction parameters had significant influence on the furfural production. The substitution of water by the saturated NaCl solution in the aqueous phase also had an important effect on the xylose and xylan conversion. The highest furfural yields were achieved up to 79.64% from xylose and 77.35% from xylan under the optimized reaction conditions (160 °C, 120 min; 160 °C, 90 min). Moreover, the prepared catalyst was stable and was reused five times with a slight decrease (10.0%) of the furfural yield. Full article
(This article belongs to the Special Issue Heterogeneous Catalysis for Environmental Remediation)
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Open AccessArticle Microwave-Assisted Synthesis of Co3(PO4)2 Nanospheres for Electrocatalytic Oxidation of Methanol in Alkaline Media
Catalysts 2017, 7(4), 119; doi:10.3390/catal7040119
Received: 16 January 2017 / Revised: 11 April 2017 / Accepted: 12 April 2017 / Published: 17 April 2017
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Abstract
Low-cost and high-performance advanced electrocatalysts for direct methanol fuel cells are of key significance for the improvement of environmentally-pleasant energy technologies. Herein, we report the facile synthesis of cobalt phosphate (Co3(PO4)2) nanospheres by a microwave-assisted process and
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Low-cost and high-performance advanced electrocatalysts for direct methanol fuel cells are of key significance for the improvement of environmentally-pleasant energy technologies. Herein, we report the facile synthesis of cobalt phosphate (Co3(PO4)2) nanospheres by a microwave-assisted process and utilized as an electrocatalyst for methanol oxidation. The phase formation, morphological surface structure, elemental composition, and textural properties of the synthesized (Co3(PO4)2) nanospheres have been examined by powder X-ray diffraction (XRD), Fourier transform-infrared spectroscopy (FT-IR), field emission-scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), and nitrogen adsorption-desorption isotherm investigations. The performance of an electrocatalytic oxidation of methanol over a Co3(PO4)2 nanosphere-modified electrode was evaluated in an alkaline solution using cyclic voltammetry (CV) and chronopotentiometry (CP) techniques. Detailed studies were made for the methanol oxidation by varying the experimental parameters, such as catalyst loading, methanol concentration, and long-term stability for the electro-oxidation of methanol. The good electrocatalytic performances of Co3(PO4)2 should be related to its good surface morphological structure and high number of active surface sites. The present investigation illustrates the promising application of Co3(PO4)2 nanospheres as a low-cost and more abundant electrocatalyst for direct methanol fuel cells. Full article
(This article belongs to the Special Issue Enabling Technologies toward Green Catalysis)
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Open AccessArticle Quantitative Structure-Thermostability Relationship of Late Transition Metal Catalysts in Ethylene Oligo/Polymerization
Catalysts 2017, 7(4), 120; doi:10.3390/catal7040120
Received: 23 February 2017 / Revised: 30 March 2017 / Accepted: 14 April 2017 / Published: 18 April 2017
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Abstract
Quantitative structure–thermostability relationship was carried out for four series of bis(imino)pyridine iron (cobalt) complexes and α-diimine nickel complexes systems in ethylene oligo/polymerization. Three structural parameters were correlated with thermal stability, including bond order of metal-nitrogen (B), minimum distance (D
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Quantitative structure–thermostability relationship was carried out for four series of bis(imino)pyridine iron (cobalt) complexes and α-diimine nickel complexes systems in ethylene oligo/polymerization. Three structural parameters were correlated with thermal stability, including bond order of metal-nitrogen (B), minimum distance (D) between central metal and ortho-carbon atoms on the aryl moiety and dihedral angle (α) of a central five-membered ring. The variation degree of catalytic activities between optimum and room temperatures (AT) was calculated to describe the thermal stability of the complex. By multiple linear regression analysis (MLRA), the thermal stability presents good correlation with three structural parameters with the correlation coefficients (R2) over 0.95. Furthermore, the contributions of each parameter were evaluated. Through this work, it is expected to help the design of a late transition metal complex with thermal stability at the molecular level. Full article
(This article belongs to the Special Issue Computational Methods and Their Application in Catalysis)
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Open AccessArticle Promotive Effect of Sn2+ on Cu0/Cu+ Ratio and Stability Evolution of Cu/SiO2 Catalyst in the Hydrogenation of Dimethyl Oxalate
Catalysts 2017, 7(4), 122; doi:10.3390/catal7040122
Received: 26 March 2017 / Revised: 13 April 2017 / Accepted: 14 April 2017 / Published: 19 April 2017
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Abstract
The influence of Sn2+doping on the structure and performance of silica supported copper catalyst was systematically investigated and characterised. Catalytic evaluation showed that the suitable content of Sn2+ introduced into a Cu/SiO2 catalyst evidently improved the catalytic activity and
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The influence of Sn2+doping on the structure and performance of silica supported copper catalyst was systematically investigated and characterised. Catalytic evaluation showed that the suitable content of Sn2+ introduced into a Cu/SiO2 catalyst evidently improved the catalytic activity and stability of ethylene glycol synthesis from dimethyl oxalate. X-ray diffraction and X-ray auger electron spectroscopy indicated that the Cu0/Cu+ ratio gradually increased with increasing Sn2+ content, and an appropriate proportion of Cu0/Cu+ ratio played a very significant role in this reaction. Transmission electron microscopy revealed that the active copper particles in the Cu-xSn/SiO2 catalyst were smaller than those of the Cu/SiO2 catalyst. This result may be due to the introduction of Sn2+ species transformed into SnO2. Furthermore, SnO2 effectively segregated the active copper. These effects are beneficial in inhibiting the aggregation of copper in the catalysts, thereby improving the stability of the catalyst and prolonging the life span. Full article
(This article belongs to the Special Issue Small Molecule Activation and Catalysis)
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Open AccessArticle A Simple and Efficient Process for Large Scale Glycerol Oligomerization by Microwave Irradiation
Catalysts 2017, 7(4), 123; doi:10.3390/catal7040123
Received: 28 February 2017 / Revised: 29 March 2017 / Accepted: 11 April 2017 / Published: 19 April 2017
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Abstract
Herein, an optimized method for 100 g scale synthesis of glycerol oligomers using a microwave multimode source and the low priced K2CO3 as catalyst is reported. This method allows the complete conversion of glycerol to its oligomers in only 30
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Herein, an optimized method for 100 g scale synthesis of glycerol oligomers using a microwave multimode source and the low priced K2CO3 as catalyst is reported. This method allows the complete conversion of glycerol to its oligomers in only 30 min, yielding molecular weights up to 1000 g mol−1. Furthermore, a simple iterative purification process, involving the precipitation of the crude product in acetone and methanol, affords a final product composed of larger oligomers with a narrow dispersity (D < 1.5). Full article
(This article belongs to the Special Issue Catalysis of Biomass-Derived Molecules)
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Open AccessArticle In Search of Governing Gas Flow Mechanism through Metal Solid Foams
Catalysts 2017, 7(4), 124; doi:10.3390/catal7040124
Received: 9 February 2017 / Revised: 11 April 2017 / Accepted: 17 April 2017 / Published: 21 April 2017
Cited by 1 | PDF Full-text (4749 KB) | HTML Full-text | XML Full-text
Abstract
Solid foams have been intensely studied as promising structured catalytic internals. However, mechanisms governing flow and transport phenomena within the foam structures have not been properly addressed in the literature. The aim of this study was to consider such flow mechanisms based on
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Solid foams have been intensely studied as promising structured catalytic internals. However, mechanisms governing flow and transport phenomena within the foam structures have not been properly addressed in the literature. The aim of this study was to consider such flow mechanisms based on our experimental results on flow resistance. Two mechanisms were considered: developing laminar flow in a short capillary channel (flow-through model), and flow around an immersed solid body, either a cylinder or sphere (flow-around model). Flow resistance experiments were performed on three aluminum foams of 10, 20, and 40 PPI (pores per inch), using a 57 mm ID test column filled with the foams studied. The foam morphology was examined using microtomography and optical microscopy to derive the geometric parameters applied in the model equations. The flow-through model provided an accuracy of 25% for the experiments. The model channel diameter was the foam cell diameter, and the channel length was the strut thickness. The accuracy of the flow-around model was only slightly worse (35%). It was difficult to establish the geometry of the immersed solid body (sphere or cylinder) because experiment characteristics tended to change from sphere to cylinder with increasing PPI value. Full article
(This article belongs to the Special Issue Structured and Micro-Structured Catalysts and Reactors)
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Open AccessArticle Preparation of Rh/Ni Bimetallic Nanoparticles and Their Catalytic Activities for Hydrogen Generation from Hydrolysis of KBH4
Catalysts 2017, 7(4), 125; doi:10.3390/catal7040125
Received: 20 March 2017 / Revised: 16 April 2017 / Accepted: 18 April 2017 / Published: 23 April 2017
Cited by 2 | PDF Full-text (5358 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
ISOBAM-104 protected Rh/Ni bimetallic nanoparticles (BNPs) of 3.1 nm in diameter were synthesized by a co-reduction method with a rapid injection of KBH4 solution. The catalytic activities of as-prepared BNPs for hydrogen generation from hydrolysis of a basic KBH4 solution were
[...] Read more.
ISOBAM-104 protected Rh/Ni bimetallic nanoparticles (BNPs) of 3.1 nm in diameter were synthesized by a co-reduction method with a rapid injection of KBH4 solution. The catalytic activities of as-prepared BNPs for hydrogen generation from hydrolysis of a basic KBH4 solution were evaluated. Ultraviolet-visible spectrophotometry (UV-Vis), transmission electron microscopy (TEM), and high-resolution transmission electron microscopy (HRTEM) were employed to characterize the structure, particle size, and chemical composition of the resultant BNPs. Catalytic activities for hydrolysis of KBH4 and catalytic kinetics of prepared BNPs were also investigated. It was shown that Rh/Ni BNPs displayed much higher catalytic activities than that of Rh or Ni monometallic nanoparticles (MNPs), and the prepared Rh10Ni90 BNPs possessed the highest catalytic activities with a value of 11580 mol-H2·h−1·mol-Rh−1. The high catalytic activities of Rh/Ni BNPs could be attributed to the electron transfer effect between Rh and Ni atoms, which was confirmed by a density functional theory (DFT) calculation. The apparent activation energy for hydrogen generation of the prepared Rh10Ni90 BNPs was about 47.2 ± 2.1 kJ/mol according to a kinetic study. Full article
(This article belongs to the Special Issue Small Molecule Activation and Catalysis)
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Review

Jump to: Research

Open AccessReview Eco-Friendly Physical Activation Methods for Suzuki–Miyaura Reactions
Catalysts 2017, 7(4), 98; doi:10.3390/catal7040098
Received: 31 December 2016 / Revised: 9 March 2017 / Accepted: 16 March 2017 / Published: 23 March 2017
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Abstract
Eco-compatible activation methods in Suzuki–Miyaura cross-coupling reactions offer challenging opportunities for the design of clean and efficient synthetic processes. The main enabling technologies described in the literature are microwaves, ultrasound, grinding (mechanochemistry) and light. These methods can be performed in water or other
[...] Read more.
Eco-compatible activation methods in Suzuki–Miyaura cross-coupling reactions offer challenging opportunities for the design of clean and efficient synthetic processes. The main enabling technologies described in the literature are microwaves, ultrasound, grinding (mechanochemistry) and light. These methods can be performed in water or other green solvents with phase-transfer catalysis or even in solventless conditions. In this review, the authors will summarize the progress in this field mainly from 2010 up to the present day. Full article
(This article belongs to the Special Issue Suzuki–Miyaura Cross-Coupling Reaction and Potential Applications)
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Open AccessFeature PaperReview Visible-Light-Active TiO2-Based Hybrid Nanocatalysts for Environmental Applications
Catalysts 2017, 7(4), 100; doi:10.3390/catal7040100
Received: 20 January 2017 / Revised: 14 March 2017 / Accepted: 22 March 2017 / Published: 25 March 2017
Cited by 3 | PDF Full-text (7351 KB) | HTML Full-text | XML Full-text
Abstract
Photocatalytic nanomaterials such as TiO2 are receiving a great deal of attention owing to their potential applications in environmental remediation. Nonetheless, the low efficiency of this class of materials in the visible range has, so far, hampered their large-scale application. The increasing
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Photocatalytic nanomaterials such as TiO2 are receiving a great deal of attention owing to their potential applications in environmental remediation. Nonetheless, the low efficiency of this class of materials in the visible range has, so far, hampered their large-scale application. The increasing demand for highly efficient, visible-light-active photocatalysts can be addressed by hybrid nanostructured materials in which two or more units, each characterised by peculiar physical properties, surface chemistry and morphology, are combined together into a single nano-object with unprecedented chemical–physical properties. The present review intends to focus on hybrid nanomaterials, based on TiO2 nanoparticles able to perform visible-light-driven photocatalytic processes for environmental applications. We give a brief overview of the synthetic approaches recently proposed in the literature to synthesise hybrid nanocrystals and discuss the potential applications of such nanostructures in water remediation, abatement of atmospheric pollutants (including NOx and volatile organic compounds (VOCs)) and their use in self-cleaning surfaces. Full article
(This article belongs to the Special Issue Heterogeneous Catalysis for Environmental Remediation)
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Open AccessFeature PaperReview Characterization of MoVTeNbOx Catalysts during Oxidation Reactions Using In Situ/Operando Techniques: A Review
Catalysts 2017, 7(4), 109; doi:10.3390/catal7040109
Received: 5 January 2017 / Revised: 3 April 2017 / Accepted: 6 April 2017 / Published: 8 April 2017
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Abstract
Light alkanes are abundant in shale gas resources. The bulk mixed metal oxide MoVTe(Sb)NbOx catalysts play a very important role in dehydrogenation and selective oxidation reactions of these short hydrocarbons to produce high-value chemicals. This catalyst system mainly consists of M1 and
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Light alkanes are abundant in shale gas resources. The bulk mixed metal oxide MoVTe(Sb)NbOx catalysts play a very important role in dehydrogenation and selective oxidation reactions of these short hydrocarbons to produce high-value chemicals. This catalyst system mainly consists of M1 and less-active M2 crystalline phases. Due to their ability to directly monitor the catalysts under the relevant industrial conditions, in situ/operando techniques can provide information about the nature of active sites, surface intermediates, and kinetics/mechanisms, and may help with the synthesis of new and better catalysts. Sophisticated catalyst design and understanding is necessary to achieve the desired performance (activity, selectivity, lifetime, etc.) at reasonable reaction conditions (temperature, pressure, etc.). This article critically reviews the progress made in research of these MoVTe(Sb)NbOx catalysts in oxidation reactions mainly through in situ/operando techniques and suggests the future direction needed to realize the industrialization of these catalysts. Full article
(This article belongs to the Special Issue In Situ and Operando Characterization in Catalysis)
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Open AccessReview Improving the Stability of Cold-Adapted Enzymes by Immobilization
Catalysts 2017, 7(4), 112; doi:10.3390/catal7040112
Received: 13 January 2017 / Revised: 30 March 2017 / Accepted: 4 April 2017 / Published: 12 April 2017
Cited by 1 | PDF Full-text (629 KB) | HTML Full-text | XML Full-text
Abstract
Cold-adapted enzymes have gained considerable attention as biocatalysts that show high catalytic activity at low temperatures. However, the use of cold-adapted enzymes at ambient temperatures has been hindered by their low thermal stabilities caused by their inherent structural flexibilities. Accordingly, protein engineering and
[...] Read more.
Cold-adapted enzymes have gained considerable attention as biocatalysts that show high catalytic activity at low temperatures. However, the use of cold-adapted enzymes at ambient temperatures has been hindered by their low thermal stabilities caused by their inherent structural flexibilities. Accordingly, protein engineering and immobilization have been employed to improve the thermal stability of cold-adapted enzymes. Immobilization has been shown to increase the thermal stability of cold-adapted enzymes at the critical temperatures at which denaturation begins. This review summarizes progress in immobilization of cold-adapted enzymes as a strategy to improve their thermal and organic solvent stabilities. Full article
(This article belongs to the Special Issue Immobilized Enzymes: Strategies for Enzyme Stabilization)
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Open AccessFeature PaperReview Abatement of VOCs Using Packed Bed Non-Thermal Plasma Reactors: A Review
Catalysts 2017, 7(4), 113; doi:10.3390/catal7040113
Received: 20 December 2016 / Revised: 6 April 2017 / Accepted: 7 April 2017 / Published: 12 April 2017
Cited by 1 | PDF Full-text (2436 KB) | HTML Full-text | XML Full-text
Abstract
Non thermal plasma (NTP) reactors packed with non-catalytic or catalytic packing material have been widely used for the abatement of volatile organic compounds such as toluene, benzene, etc. Packed bed reactors are single stage reactors where the packing material is placed directly in
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Non thermal plasma (NTP) reactors packed with non-catalytic or catalytic packing material have been widely used for the abatement of volatile organic compounds such as toluene, benzene, etc. Packed bed reactors are single stage reactors where the packing material is placed directly in the plasma discharge region. The presence of packing material can alter the physical (such as discharge characteristics, power consumption, etc.) and chemical characteristics (oxidation and destruction pathway, formation of by-products, etc.) of the reactor. Thus, packed bed reactors can overcome the disadvantages of NTP reactors for abatement of volatile organic compounds (VOCs) such as lower energy efficiency and formation of unwanted toxic by-products. This paper aims at reviewing the effect of different packing materials on the abatement of different aliphatic, aromatic and chlorinated volatile organic compounds. Full article
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Open AccessFeature PaperReview Merging Metallic Catalysts and Sonication: A Periodic Table Overview
Catalysts 2017, 7(4), 121; doi:10.3390/catal7040121
Received: 8 March 2017 / Revised: 7 April 2017 / Accepted: 14 April 2017 / Published: 19 April 2017
Cited by 1 | PDF Full-text (8874 KB) | HTML Full-text | XML Full-text
Abstract
This account summarizes and discusses recent examples in which the combination of ultrasonic waves and metal-based reagents, including metal nanoparticles, has proven to be a useful choice in synthetic planning. Not only does sonication often enhance the activity of the metal catalyst/reagent, but
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This account summarizes and discusses recent examples in which the combination of ultrasonic waves and metal-based reagents, including metal nanoparticles, has proven to be a useful choice in synthetic planning. Not only does sonication often enhance the activity of the metal catalyst/reagent, but it also greatly enhances the synthetic transformation that can be conducted under milder conditions relative to conventional protocols. For the sake of clarity, we have adopted a structure according to the periodic-table elements or families, distinguishing between bulk metal reagents and nanoparticles, as well as the supported variations, thus illustrating the characteristics of the method under consideration in target synthesis. The coverage focuses essentially on the last decade, although the discussion also strikes a comparative balance between the more recent advancements and past literature. Full article
(This article belongs to the Special Issue Enabling Technologies toward Green Catalysis)
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