Immobilization of Ir(OH)3 Nanoparticles in Mesospaces of Al-SiO2 Nanoparticles Assembly to Enhance Stability for Photocatalytic Water Oxidation

Iridium hydroxide (Ir(OH)3) nanoparticles exhibiting high catalytic activity for water oxidation were immobilized inside mesospaces of a silica-nanoparticles assembly (SiO2NPA) to suppress catalytic deactivation due to agglomeration. The Ir(OH)3 nanoparticles immobilized in SiO2NPA (Ir(OH)3/SiO2NPA) catalyzed water oxidation by visible light irradiation of a solution containing persulfate ion (S2O82−) and tris(2,2′-bipyridine)ruthenium(II) ion ([RuII(bpy)3]2+) as a sacrificial electron acceptor and a photosensitizer, respectively. The yield of oxygen (O2) based on the used amount of S2O82− was maintained over 80% for four repetitive runs using Ir(OH)3/SiO2NPA prepared by the co-accumulation method, although the yield decreased for the reaction system using Ir(OH)3/SiO2NPA prepared by the equilibrium adsorption method or Ir(OH)3 nanoparticles without SiO2NPA support under the same reaction conditions. Immobilization of Ir(OH)3 nanoparticles in Al3+-doped SiO2NPA (Al-SiO2NPA) results in further enhancement of the catalytic stability with the yield of more than 95% at the fourth run of the repetitive experiments.

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Chiral CuO@Ni with continuous macroporous framework and its high catalytic activity for electrochemical water oxidation

International Journal of Hydrogen Energy ◽

10.1016/j.ijhydene.2020.12.210 ◽

2021 ◽

Vol 46 (13) ◽

pp. 8922-8931

Author(s):

Wenyan Zhang ◽

Wei Wang ◽

Yingfei Hu ◽

Hangmin Guan ◽

Xiaoli Yang ◽

...

Keyword(s):

Catalytic Activity ◽

Water Oxidation ◽

High Catalytic Activity

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Catalytic Synthesis of Benzyl Acetate by Diatomite Supported Waugh-Type (NH4)6[MnMo9O32] •8H2O

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.483.38 ◽

2013 ◽

Vol 483 ◽

pp. 38-41

Author(s):

Shu Heng Liu

Keyword(s):

Acetic Acid ◽

Catalytic Activity ◽

Reaction Time ◽

Catalytic Synthesis ◽

Orthogonal Test ◽

Solid Catalyst ◽

High Catalytic Activity ◽

Benzyl Acetate ◽

Reaction Conditions ◽

Catalyst Dosage

Take Waugh-Type (NH4)6[MnMo9O32] •8H2O absorbed on diatomite and prepared supported solid catalyst. The properties of the catalyst were studied through the synthesis of benzyl acetate. The appropriate reaction conditions were obtained by orthogonal test: mole ratio of acetic acid to benzyl alcohol was 2.5:1.0, the catalyst dosage was 1.6g, the water carrying agent toluene dosage was 2.5ml, reaction time was 150min, esterification yield was 87.4%. The catalyst are high catalytic activity and non- polluting, and could be reused.

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Active phase of highly active Co3O4 catalyst for synthetic natural gas production

RSC Advances ◽

10.1039/c4ra12214c ◽

2014 ◽

Vol 4 (100) ◽

pp. 57185-57191 ◽

Cited By ~ 5

Author(s):

Baowei Wang ◽

Sihan Liu ◽

Zongyuan Hu ◽

Zhenhua Li ◽

Xinbin Ma

Keyword(s):

Catalytic Activity ◽

Low Temperature ◽

Natural Gas ◽

Active Phase ◽

Gas Production ◽

High Catalytic Activity ◽

Co Methanation ◽

Synthetic Natural Gas ◽

Highly Active ◽

Catalytic Stability

Co3O4 nanoparticles showed high catalytic activity for low temperature CO methanation. CoO is the active phase of the catalyst. Pre-reduction treatment can improve catalytic stability.

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Pt/porous nanorods of ceria as efficient high temperature catalysts with remarkable catalytic stability for carbon dioxide reforming of methane

Journal of Materials Chemistry A ◽

10.1039/c5ta03448e ◽

2015 ◽

Vol 3 (35) ◽

pp. 18074-18082 ◽

Cited By ~ 18

Author(s):

Zhiyun Zhang ◽

Jing Li ◽

Wei Gao ◽

Yuanyuan Ma ◽

Yongquan Qu

Keyword(s):

Carbon Dioxide ◽

Thermal Stability ◽

Catalytic Activity ◽

Storage Capacity ◽

Oxygen Storage Capacity ◽

Oxygen Storage ◽

High Catalytic Activity ◽

Carbon Dioxide Reforming ◽

Catalytic Stability ◽

High Oxygen Storage Capacity

Pt/porous nanorods of CeO2 with a large surface area, a high oxygen storage capacity and a remarkable thermal stability exhibit high catalytic activity and stability for the carbon dioxide reforming of methane reaction at 800 °C.

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Catalytic Oxidative/Extractive Desulfurization of Model Oil using Transition Metal Substituted Phosphomolybdates-Based Ionic Liquids

Catalysts ◽

10.3390/catal8120639 ◽

2018 ◽

Vol 8 (12) ◽

pp. 639 ◽

Cited By ~ 7

Author(s):

Yunlei Li ◽

Yanjie Zhang ◽

Panfeng Wu ◽

Caiting Feng ◽

Ganglin Xue

Keyword(s):

Catalytic Activity ◽

Ionic Liquids ◽

Transition Metal ◽

Sulfur Removal ◽

Oxidative Desulfurization ◽

High Catalytic Activity ◽

Reaction Conditions ◽

Extraction Solvent ◽

Model Oil ◽

Optimal Reaction

Polyoxometalates based ionic liquids (POM-ILs) exhibit a high catalytic activity in oxidative desulfurization. In this paper, four new POM-IL hybrids based on transition metal mono-substituted Keggin-type phosphomolybdates, [Bmim]5[PMo11M(H2O)O39] (Bmim = 1-butyl 3-methyl imidazolium; M = Co2+, Ni2+, Zn2+, and Mn2+), have been synthesized and used as catalysts for the oxidation/extractive desulfurization of model oil, in which ILs are used as the extraction solvent and H2O2 as an oxidant under very mild conditions. The factors that affected the desulfurization efficiency were studied and the optimal reaction conditions were obtained. The results showed that the [Bmim]5[PMo11Co(H2O)O39] catalyst demonstrated the best catalytic activity, with sulfur-removal of 99.8%, 85%, and 63% for dibenzothiophene (DBT), 4,6-dimethyldibenzothiophene (4,6-DMDBT), and benzothiophene (BT), respectively, in the case of extraction combining with a oxidative desulfurization system under optimal reaction conditions (5 mL model oil (S content 500 ppm), n(catalyst) = 4 μmol, n(H2O2)/n(Substrate) = 5, T = 50 °C for 60 min with [Omim]BF4 (1 mL) as the extractant). The catalyst can be recycled at least 8 times, and still has stability and high catalytic activity for consecutive desulfurization. Probable reaction mechanisms have been proposed for catalytic oxidative/extractive desulfurization.

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Characterization and Catalytic-Site-Analysis of an Aldo-Keto Reductase with Excellent Solvent Tolerance

Catalysts ◽

10.3390/catal10101121 ◽

2020 ◽

Vol 10 (10) ◽

pp. 1121

Author(s):

Rui Pei ◽

Weiliang Wu ◽

Yuqian Zhang ◽

Libing Tian ◽

Wei Jiang ◽

...

Keyword(s):

Catalytic Activity ◽

Organic Solvent ◽

Organic Solvents ◽

Reaction System ◽

Catalytic Site ◽

Solvent Tolerance ◽

Chiral Alcohols ◽

High Catalytic Activity ◽

Site Analysis ◽

Substrate Spectrum

Aldo-keto reductases (AKRs) mediated stereoselective reduction of prochiral carbonyl compounds is an efficient way of preparing single enantiomers of chiral alcohols due to their high chemo-, enantio-, and regio-selectivity. To date, the application of AKRs in the asymmetric synthesis of chiral alcohols has been limited, due to the challenges of cloning and purifying. In this work, the aldo-keto reductase (AKR3-2-9) from Bacillus sp. was obtained, purified and proved to be NADPH-dependent. It exhibits good bioactivity and stability at 37 °C, pH 6.0. AKR3-2-9 is catalytically active on 11 pairs of substrates such as 3-methylcyclohexanone and methyl pyruvate, among which it showed the highest catalytic activity for acetylacetone. In addition, AKR3-2-9 was able to be resistant to five common organic solvents such as methanol and ethanol, it retained high catalytic activity even in a reaction system containing 10% v/v organic solvent for 6 h, which indicates its broad substrate spectrum and exceptional organic solvent tolerance. Furthermore, its three-dimensional structure was constructed and catalytic-site-analysis of the enzyme was conducted. Notably, it was capable of catalyzing the reaction of the key intermediates of duloxetine. The extensive substrate spectrum and predominant organic solvents resistance makes AK3-2-9 a promising enzyme which can be potentially applied in medicine synthesis.

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Synthesis of FePcS–PMA–LDH Cointercalation Composite with Enhanced Visible Light Photo-Fenton Catalytic Activity for BPA Degradation at Circumneutral pH

Materials ◽

10.3390/ma13081951 ◽

2020 ◽

Vol 13 (8) ◽

pp. 1951 ◽

Cited By ~ 1

Author(s):

Fenglian Huang ◽

Shiqiang Tian ◽

Yan Qi ◽

Erping Li ◽

Liangliang Zhou ◽

...

Keyword(s):

Catalytic Activity ◽

Bisphenol A ◽

Visible Light ◽

Layered Double Hydroxides ◽

Electrochemical Impedance ◽

Reaction System ◽

High Catalytic Activity ◽

Exchange Method ◽

Double Hydroxides ◽

Circumneutral Ph

(1) Background: Iron tetrasulfophthalocyanine with a large nonlinear optical coefficient, good stability, and high catalytic activity has aroused the attention of researchers in the field of photo-Fenton reaction. Further improvement of the visible light photo-Fenton catalytic activity under circumneutral pH conditions for their practical application is still of great importance. (2) Methods: In this paper, iron tetrasulfophthalocyanine (FePcS) and phosphomolybdic acid (PMA) cointercalated layered double hydroxides (LDH) were synthesized by the ion-exchange method. All samples were fully characterized by various techniques and the results showed that FePcS and PMA were successfully intercalated in layered double hydroxides and the resulted compound exhibited strong absorption in the visible light region. The cointercalation compound was tested as a heterogeneous catalyst for the visible light photo-Fenton degradation of bisphenol A (BPA) at circumneutral pH. (3) Results: The results showed that the degradation and total organic carbon removal efficiencies of bisphenol A were 100% and 69.2%, respectively. (4) Conclusions: The cyclic voltammetry and electrochemical impedance spectroscopy measurements demonstrated that the main contribution of PMA to the enhanced photo-Fenton activity of FePcS–PMA–LDH comes from the acceleration of electron transfer in the reaction system. Additionally, the possible reaction mechanism in the photo-Fenton system catalyzed by FePcS–PMA–LDH was also proposed.

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Effect of Sulfation on Zirconia-Pillared Montmorillonite to the Catalytic Activity in Microwave-Assisted Citronellal Conversion

International Journal of Chemical Engineering ◽

10.1155/2014/950190 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7 ◽

Cited By ~ 3

Author(s):

Is Fatimah ◽

Dwiarso Rubiyanto ◽

Thorikul Huda

Keyword(s):

Catalytic Activity ◽

Surface Acidity ◽

Total Pore Volume ◽

High Catalytic Activity ◽

X Ray Diffraction ◽

Adsorption Method ◽

X Ray ◽

Pillared Montmorillonite ◽

Microwave Assisted ◽

Tandem Cyclization

Preparation of sulfated zirconia-pillared montmorillonite was carried out in two steps; zirconia pillarization and sulfation to zirconia-pillared montmorillonite. The prepared materials were characterized by using X-ray diffraction (XRD), measurement of the specific surface area, total pore volume and pore size distribution by the N2adsorption method, scanning electron microscopy-energy dispersive X-ray (SEM-EDX), and surface acidity determination by using pyridine adsorption-FTIR analysis. The activity of the materials as catalysts was evaluated for a microwave-assisted conversion of citronellal. The results showed that the prepared materials had a physicochemical character that promoted high catalytic activity to convert citronellal. From varied Zr content and study of the effect of sulfation on the activity, it was found that Zr content and sulfation increase the surface acidity of the material as shown by the higher total conversion and tendency to produce menthol as a product of the tandem cyclization-hydrogenation mechanism.

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