scholarly journals A covalent triazine framework-based heterogenized Al–Co bimetallic catalyst for the ring-expansion carbonylation of epoxide to β-lactone

RSC Advances ◽  
2017 ◽  
Vol 7 (8) ◽  
pp. 4635-4638 ◽  
Author(s):  
Senkuttuvan Rajendiran ◽  
Prakash Natarajan ◽  
Sungho Yoon
Keyword(s):  
Propylene Oxide ◽  
High Selectivity ◽  
Bimetallic Catalyst ◽  
Ring Expansion ◽  
Heterogenized Catalyst ◽  
Covalent Triazine Framework

The recyclable and heterogenized catalyst [bpy-CTF-AI(OTf)2][Co(CO)4] (bpy = bipyridine) efficiently converts propylene oxide into β-butyrolactone with high selectivity.

Cyclic Alkyl(aryl)boranes for 1,1-Carboboration of Monoalkynyltin Compounds

2013 ◽  
Vol 68 (5-6) ◽  
pp. 493-502 ◽  
Author(s):  
Bernd Wrackmeyer ◽  
Peter Thoma ◽  
Wolfgang Milius
Keyword(s):  
Solid State ◽  
High Selectivity ◽  
Ring Expansion ◽  
Membered Ring ◽  
Reaction Products ◽  
State Structure ◽  
Alkyl Aryl ◽  
X Ray ◽  
X Ray Crystallography ◽  
Nmr Techniques

Two cyclic alkyl(aryl)boranes, a 1-bora-indane derivative 1, and a tricyclic derivative 4, containing the boron atom in a six-membered ring, were structurally characterized by NMR techniques in solution. The solid-state structure of the 1-bora-indane 1 was determined by X-ray crystallography. The reactivity of these cyclic alkyl(aryl)boranes towards monoalkynyltin compounds, Me3Sn-C≡C-Me and Me3Sn-C C-Fc (Fc=ferrocenyl), was studied using multinuclear magnetic resonance methods (1H, 11B, 13C, 119Sn NMR). Novel alkenylboranes were formed by 1,1-carboboration reactions. This process involves an expansion of both five- and six-membered rings. Insertion into the respective B-C(aryl) bond was preferred with high selectivity. In the case of the six-membered ring in 4, the ring expansion to seven-membered rings proved to be readily reversible, and the thermodynamically stable reaction products were formed by ring contraction and concomitant transfer of the exocyclic B-nPr group

Property of Hydrogenated Nitrile Rubber Catalyzed by a Novel Rh-Ru Bimetallic System

2006 ◽  
Vol 11-12 ◽  
pp. 375-378
Author(s):  
Ming Yao ◽  
Dong Heng Zhang ◽  
Rui Qing Xu ◽  
Kuei Hsien Hsu ◽  
Yu Zhen Zhong
Keyword(s):  
Mechanical Properties ◽  
Molecular Weight ◽  
High Selectivity ◽  
Bimetallic Catalyst ◽  
Nitrile Rubber ◽  
Homogeneous Catalyst ◽  
Bimetallic Complex ◽  
Bimetallic System ◽  
Relative Molecular Weight ◽  
Novel Catalyst

Rh-Ru bimetallic complex is a novel catalyst used to hydrogenate nitrile rubber, which has high activity and high selectivity. Hydrogenated nitrile rubber with a degree of hydrogenation over 99% and gel-free was obtained using this homogeneous catalyst. In this paper, relative molecular weight and mechanical properties of three types of HNBR, including HNBR hydrogenated by Rh-Ru bimetallic catalyst, Therban A3406 and Zetpol 2000L, were analyzed and compared. The results showed that the relative molecular weight of HNBR increased a little after hydrogenation compared to NBR, its mechanical properties were superior to those of Therban A3406 and Zetpol 2000L, and their oil resistant and rheological curves at 130°C and 140°C in the range of shear rate 0∼100s-1 were similar.

MZ Solid Catalysts for Synthesis of 1-Methoxy-2-Propanol with High Selectivity

2012 ◽  
Vol 616-618 ◽  
pp. 1717-1720
Author(s):  
Yong Jie Wang ◽  
Mu Zhang
Keyword(s):  
Catalytic Activity ◽  
Alkali Metal ◽  
Propylene Oxide ◽  
Oxide Catalyst ◽  
High Selectivity ◽  
Catalyst Activity ◽  
Complex Oxide ◽  
Solid Catalysts ◽  
New Type ◽  
Selective Access

This document explains and demonstrates the problem of Methanol and propylene oxide propoxylation, ZrO2 load active alkali metal oxides MgO the catalytic propoxylation method, analyzed a new type of catalyst activity and selectivity. The results show that the synthesis of MZ complex oxide as a catalyst for the reaction of Methanol substrate, through the catalytic reaction of propylene oxide, selective access to the propylene glycol ether, High selectivity synthesis 1-Methoxy-2-propanol. Synthesis of complex oxide catalyst MZ series in the course of the performance of the primary ether good selectivity, Primary ether, second ether ratio greater than 12, and the catalytic activity is also high (about 91% of all).

scholarly journals Atomically Dispersed Fe-Co Bimetallic Catalysts for the Promoted Electroreduction of Carbon Dioxide

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Zhangsen Chen ◽  
Gaixia Zhang ◽  
Yuren Wen ◽  
Ning Chen ◽  
Weifeng Chen ◽  
...  
Keyword(s):  
Bimetallic Catalysts ◽  
Active Sites ◽  
High Performance ◽  
High Selectivity ◽  
Bimetallic Catalyst ◽  
Hydrogen Electrode ◽  
Zeolitic Imidazolate Framework ◽  
Faradaic Efficiency ◽  
Dispersed Catalysts ◽  
Wide Potential

AbstractThe electroreduction reaction of CO2 (ECO2RR) requires high-performance catalysts to convert CO2 into useful chemicals. Transition metal-based atomically dispersed catalysts are promising for the high selectivity and activity in ECO2RR. This work presents a series of atomically dispersed Co, Fe bimetallic catalysts by carbonizing the Fe-introduced Co-zeolitic-imidazolate-framework (C–Fe–Co–ZIF) for the syngas generation from ECO2RR. The synergistic effect of the bimetallic catalyst promotes CO production. Compared to the pure C–Co–ZIF, C–Fe–Co–ZIF facilitates CO production with a CO Faradaic efficiency (FE) boost of 10%, with optimal FECO of 51.9%, FEH2 of 42.4% at − 0.55 V, and CO current density of 8.0 mA cm−2 at − 0.7 V versus reversible hydrogen electrode (RHE). The H2/CO ratio is tunable from 0.8 to 4.2 in a wide potential window of − 0.35 to − 0.8 V versus RHE. The total FECO+H2 maintains as high as 93% over 10 h. The proper adding amount of Fe could increase the number of active sites and create mild distortions for the nanoscopic environments of Co and Fe, which is essential for the enhancement of the CO production in ECO2RR. The positive impacts of Cu–Co and Ni–Co bimetallic catalysts demonstrate the versatility and potential application of the bimetallic strategy for ECO2RR.

scholarly journals Fine cubic Cu2O nanocrystals as highly selective catalyst for propylene epoxidation with molecular oxygen

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Wei Xiong ◽  
Xiang-Kui Gu ◽  
Zhenhua Zhang ◽  
Peng Chai ◽  
Yijing Zang ◽  
...  
Keyword(s):  
Molecular Oxygen ◽  
Partial Oxidation ◽  
Propylene Oxide ◽  
High Selectivity ◽  
Active Oxygen Species ◽  
Active Oxygen ◽  
Lattice Oxygen ◽  
Oxygen Species ◽  
Propylene Epoxidation ◽  
Selective Catalyst

AbstractPropylene epoxidation with O2 to propylene oxide is a very valuable reaction but remains as a long-standing challenge due to unavailable efficient catalysts with high selectivity. Herein, we successfully explore 27 nm-sized cubic Cu2O nanocrystals enclosed with {100} faces and {110} edges as a highly selective catalyst for propylene epoxidation with O2, which acquires propylene oxide selectivity of more than 80% at 90–110 °C. Propylene epoxidation with weakly-adsorbed O2 species at the {110} edge sites exhibits a low barrier and is the dominant reaction occurring at low reaction temperatures, leading to the high propylene oxide selectivity. Such a weakly-adsorbed O2 species is not stable at high reaction temperatures, and the surface lattice oxygen species becomes the active oxygen species to participate in propylene epoxidation to propylene oxide and propylene partial oxidation to acrolein at the {110} edge sites and propylene combustion to CO2 at the {100} face sites, which all exhibit high barriers and result in decreased propylene oxide selectivity.

ZM Solid Catalysts for Synthesis of 1-Butoxy-2-Propanol with High Selectivity

2011 ◽  
Vol 415-417 ◽  
pp. 1771-1776
Author(s):  
Yong Jie Wang
Keyword(s):  
Catalytic Activity ◽  
Alkali Metal ◽  
Propylene Oxide ◽  
Oxide Catalyst ◽  
High Selectivity ◽  
Catalyst Activity ◽  
Complex Oxide ◽  
Solid Catalysts ◽  
New Type ◽  
Selective Access

This document explains and demonstrates the problem of butanol and propylene oxide propoxylation, ZrO2 load active alkali metal oxides MgO the catalytic propoxylation method, analyzed a new type of catalyst activity and selectivity. The results show that the synthesis of ZM complex oxide as a catalyst for the reaction of butanol substrate, through the catalytic reaction of propylene oxide, selective access to the propylene glycol ether, High selectivity synthesis 1-butoxy-2-propanol. Synthesis of complex oxide catalyst ZM series in the course of the performance of the primary ether good selectivity, Primary ether, second ether ratio greater than 12, and the catalytic activity is also high (about 90% of all).

scholarly journals Evaluation of favorable operating conditions for quinoline hydrodenitrogenation

2018 ◽  
Vol 24 (4) ◽  
pp. 379-386
Author(s):  
Gabriel Vasconcelos ◽  
Hugo Oliveira ◽  
Rita Colman
Keyword(s):  
Nitrogen Removal ◽  
Bimetallic Catalysts ◽  
High Selectivity ◽  
Bimetallic Catalyst ◽  
Simulation Analysis ◽  
Operating Conditions ◽  
Environmental Aspects ◽  
Hydrogen Flow ◽  
Hydrogen Consumption ◽  
Key Factor

Economic and environmental aspects render nitrogen removal from oil loads increasingly more necessary. Studies have proven that it is possible to achieve high selectivity to quinoline hydrodenitrogenation products using PtMo bimetallic catalysts supported on zeolites. However, the reaction follows the route of higher hydrogen consumption. The main products in this reaction are propylcyclohexene, propylbenzene, and propylcyclohexane, being more selective for propylcyclohexane, which is directly related to increased hydrogen consumption. Therefore, the identification of the best conditions of temperature and hydrogen flow to make the process more selective for propylbenzene is of interest. The study conducted in UniSim? Software showed considerable improvements in selectivity with increasing the temperature of reaction between 450 and 500?C. Additionally, the catalytic tests confirmed that the bimetallic catalyst reached higher selectivity when the temperature of 460?C was used, as determined by simulation. The experimental results and the simulation analysis showed that molybdenum in catalysts is essential for HDN reactions and that temperature is a key factor toward propylbenzene selectivity.

Formation of C2oxygenates and ethanol from syngas on an Fe-decorated Cu-based catalyst: insight into the role of Fe as a promoter

2017 ◽  
Vol 19 (45) ◽  
pp. 30883-30894 ◽  
Author(s):  
Lixia Ling ◽  
Qiang Wang ◽  
Riguang Zhang ◽  
Debao Li ◽  
Baojun Wang
Keyword(s):  
High Selectivity ◽  
Bimetallic Catalyst ◽  
Insight Into

Fe-decorated Cu bimetallic catalyst exhibits a high selectivity to ethanol.

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