scholarly journals Highly Selective Skeletal Isomerization of Cyclohexene Over Zeolite-Based Catalysts for High-Purity Methylcyclopentene Production

2020 ◽  
Author(s):  
Hua Song ◽  
Hao Xu ◽  
Zhaofei Li ◽  
Shijun Meng ◽  
Jack Jarvis
Keyword(s):  
Experimental Data ◽  
High Purity ◽  
High Selectivity ◽  
Skeletal Isomerization ◽  
Dft Study ◽  
Mild Conditions

Abstract Cyclohexene skeletal isomerization was achieved under mild conditions over rationally designed zeolite-based catalysts with high selectivity towards methylcyclopentene and satisfactory stability for multiple runs. The favorable performance was investigated, which can be attributed to unique acidic, structural and morphologic features of optimized Co/NaUZSM-5 catalyst. Further experimental data suggested that carboncationic mechanism might be followed and the reaction mainly occurs within the internal pores of zeolite structures, which was also validated by DFT study.

scholarly journals Highly selective skeletal isomerization of cyclohexene over zeolite-based catalysts for high-purity methylcyclopentene production

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Hao Xu ◽  
Zhaofei Li ◽  
Shijun Meng ◽  
Jack Jarvis ◽  
Hua Song
Keyword(s):  
Experimental Data ◽  
High Activity ◽  
High Purity ◽  
Morphological Features ◽  
Skeletal Isomerization ◽  
Added Value ◽  
Dft Studies ◽  
Mild Conditions ◽  
Liquid Yield

AbstractCyclohexene skeletal isomerization towards methylcyclopentene is an economically favorable process due to the higher added value of the product. Traditional oxide-based catalysts face the challenge of achieving both high activity and stability. In this work, cyclohexene skeletal isomerization is achieved under mild conditions over designed zeolite-based catalysts with 96.8 wt.% liquid yield, 95.8 wt.% selectivity towards methylcyclopentene and satisfactory stability for multiple runs. The favorable performance is attributed to the unique acidic, structural and morphological features of the optimized cobalt/NaUZSM-5 catalyst. Further experimental data and DFT studies suggest that a carboncationic mechanism might be followed and that the reaction mainly occurs within the internal pores of the zeolite structures.

Preparation of L-α-Glycerophosphocholine from Natural Lecithin Catalyzed by Tert-Butylamine

2013 ◽  
Vol 641-642 ◽  
pp. 148-151
Author(s):  
Hong Ya Li ◽  
Xiao Li Zhang ◽  
Wei Li Bai ◽  
Bin Xia Zhao
Keyword(s):  
Experimental Data ◽  
High Purity ◽  
Equation Model ◽  
Mild Conditions ◽  
Tert Butylamine ◽  
Catalyst Content

L-α-glycerophosphocholine, transesterification, tert-butylamine, natural lecithin Abstract. Tert-butylamine was confirmed as effective catayst for preparing L-α-glycerophospho -choline at mild conditions. The process using this catalyst would be much simpler, since the recovery of the catalyst can be combined with the recovery of methanol by distillation. The conversion of phosphatidylcholine could reach over 98% after 4 h, with a catalyst content of 2.4% under 60 °C. The mechanism of the methanolysis reaction was proposed and the experimental data fit the equation model well. GC was used to analyze the product, it was indicated that the product had high purity, and the catalyst could get similar effect to the fresh after repeatedly used.

Eco-Friendly Synthesis of Sulphonic Acid Oxime Esters Catalyzed by 2-(1H-Benzotriazole-1-yl)-1,1,3,3-Tetramethyluronium Tetrafluoroborate

2014 ◽  
Vol 525 ◽  
pp. 93-96
Author(s):  
Wei Shi ◽  
Ji Ming Zhang ◽  
Jian Hua Zhou ◽  
Jian Hua Zhou ◽  
Song Song Ding
Keyword(s):  
High Selectivity ◽  
Sulphonic Acid ◽  
Present Approach ◽  
High Yield ◽  
Facile Synthesis ◽  
Reaction Duration ◽  
Mild Conditions ◽  
Environmental Friendly

Herein we describle a facile synthesis of sulphonic acid oxime esters in acetonitrile from the corresponding sulphonic acids and oximes catalyzed by the environmental friendly 2-(1H-benzotriazole-1-yl)-1,1,3,3-tetramethyluronium tetrafluoroborate (TBTU) in the presence of triethylamine (TEA) under mild conditions. The present approach offers the advantages of a clean reaction, simple methodology, employing readily available catalyst, short reaction duration, high selectivity and high yield.

Highly Selective Oxidation of Cinnamaldehyde to Benzaldehyde by Hydrogen Peroxide in Mild Conditions

2014 ◽  
Vol 522-524 ◽  
pp. 458-464
Author(s):  
Yuan Mei Nie ◽  
Yong Peng An ◽  
Cai Hua Peng ◽  
Xing Dong Yao
Keyword(s):  
Hydrogen Peroxide ◽  
Hydrogen Bond ◽  
Sodium Bicarbonate ◽  
Propylene Glycol ◽  
Selective Oxidation ◽  
High Selectivity ◽  
Protic Solvent ◽  
Hydrogen Bond Interaction ◽  
Mild Conditions ◽  
Effect Of Solvent

Benzaldehyde was produced from oxidation of cinnamaldehyde by hydrogen peroxide in propylene glycol in the presence of sodium bicarbonate. Protic solvent demonstrated high selectivity and the yield of benzaldehyde could reach up to 82% in propylene glycol. The effect of solvent on the selectivity was attributed to hydrogen bond interaction between the oxidation intermediate epoxide and the solvent.

scholarly journals Renewable energy storage via efficient reversible hydrogenation of piperidine captured CO2

2018 ◽  
Vol 20 (18) ◽  
pp. 4292-4298 ◽  
Author(s):  
Mi Lu ◽  
Jianghao Zhang ◽  
Yao Yao ◽  
Junming Sun ◽  
Yong Wang ◽  
...  
Keyword(s):  
Renewable Energy ◽  
Energy Storage ◽  
Reaction Kinetics ◽  
High Purity ◽  
Storage System ◽  
Mild Conditions ◽  
Hydrogen Storage System ◽  
Renewable Hydrogen ◽  
Renewable Energy Storage ◽  
High Purity Hydrogen

A highly efficient formate-piperidine-adduct based hydrogen storage system was developed. High-purity hydrogen can be produced with superior reaction kinetics under mild conditions. By integrating this system with renewable hydrogen and fuel cells, in-demand rechargeable hydrogen batteries could be realized for storing renewable energy.

scholarly journals Biomimetic and bioinspired molecular electrets. How to make them and why does the established peptide chemistry not always work?

2020 ◽  
Vol 92 (2) ◽  
pp. 275-299 ◽  
Author(s):  
Kamil Skonieczny ◽  
Eli M. Espinoza ◽  
James B. Derr ◽  
Maryann Morales ◽  
Jillian M. Clinton ◽  
...  
Keyword(s):  
High Selectivity ◽  
Science And Engineering ◽  
Peptide Chemistry ◽  
Nitrobenzoic Acid ◽  
Biological Inspiration ◽  
Mild Conditions ◽  
Amide Coupling ◽  
Synthetic Polypeptides ◽  
Electric Dipoles ◽  
Nitro Reduction

Abstract“Biomimetic” and “bioinspired” define different aspects of the impacts that biology exerts on science and engineering. Biomimicking improves the understanding of how living systems work, and builds tools for bioinspired endeavors. Biological inspiration takes ideas from biology and implements them in unorthodox manners, exceeding what nature offers. Molecular electrets, i.e. systems with ordered electric dipoles, are key for advancing charge-transfer (CT) science and engineering. Protein helices and their biomimetic analogues, based on synthetic polypeptides, are the best-known molecular electrets. The inability of native polypeptide backbones to efficiently mediate long-range CT, however, limits their utility. Bioinspired molecular electrets based on anthranilamides can overcome the limitations of their biological and biomimetic counterparts. Polypeptide helices are easy to synthesize using established automated protocols. These protocols, however, fail to produce even short anthranilamide oligomers. For making anthranilamides, the residues are introduced as their nitrobenzoic-acid derivatives, and the oligomers are built from their C- to their N-termini via amide-coupling and nitro-reduction steps. The stringent requirements for these reduction and coupling steps pose non-trivial challenges, such as high selectivity, quantitative yields, and fast completion under mild conditions. Addressing these challenges will provide access to bioinspired molecular electrets essential for organic electronics and energy conversion.

Theoretical screening of single atoms anchored on defective graphene for electrocatalytic N2 reduction reactions: a DFT study

2020 ◽  
Vol 22 (17) ◽  
pp. 9322-9329 ◽  
Author(s):  
Pingping Liu ◽  
Cheng Fu ◽  
Yafei Li ◽  
Haiyan Wei
Keyword(s):  
Dft Study ◽  
Reduction Reactions ◽  
Mild Conditions ◽  
Single Atoms ◽  
Defective Graphene

The reduction of molecular dinitrogen (N2) to ammonia (NH3) under mild conditions is attractive due to the wide application of ammonia.

PURIFICATION OF LYSOZYME BY INTRINSICALLY SHIELDED HYDROGEL BEADS

2013 ◽  
Vol 27 (19) ◽  
pp. 1341028
Author(s):  
CONG LI ◽  
R. ZHANG ◽  
L. WANG ◽  
A. BOWYER ◽  
R. EISENTHAL ◽  
...  
Keyword(s):  
Binary Mixture ◽  
High Purity ◽  
High Selectivity ◽  
Egg White ◽  
Titration Calorimetry ◽  
Binding Affinities ◽  
Affinity Separation ◽  
Hydrogel Beads ◽  
Relative Binding ◽  
Very High

Macro-sized intrinsically shielded hydrogel beads have been prepared from BSA and CM-dextran grafted with CB using a technique based on freeze-thawing gelation method. The size of the beads lies in around 500 μm. Isothemal titration calorimetry (ITC) showed that the relative binding affinities of the lysozyme for CB, compared with BSA, at pH 3.0 was stronger than that at pH 7.4. They were employed for the affinity separation of lysozyme using chromatography column. Their adsorption capacity for lysozyme at pH 3.0 is higher than that at pH 9. In a binary mixture of lysozyme and ovalbumin, the beads showed very high selectivity toward lysozyme. Lysozyme of very high purity (> 93%) was obtained from a mixture of lysozyme and ovalbumin, and 85% from egg white solution. The results indicate that the macro-sized bead can be used for the separation, purification, and recovery of lysozyme in a chromatograph column.

Selective separation of silver(I) by novel substituted thiourea

2007 ◽  
Vol 95 (8) ◽  
Author(s):  
Aslam Khan
Keyword(s):  
Experimental Data ◽  
Nitric Acid ◽  
Acid Concentration ◽  
Organic Phase ◽  
High Selectivity ◽  
Nitric Acid Concentration ◽  
Equilibration Time ◽  
Acid Solutions ◽  
Nitric Acid Solutions ◽  
Species Effect

The extraction of silver(I) from nitric acid solutions using naphthyl substituted thiourea such as 1-naphthylthiourea (ANTU) has been studied. Different variables: equilibration time, aqueous pH, chloride and extractant concentrations and organic phase diluent that could affect the extraction system were evaluated at 28.0 ± 2.0 °C. It was found that silver is quantitatively extractred by ANTU over the entire studied range of nitric acid concentration. Extraction of silver by ANTU is fast and equilibration was achieved in less than five minutes. Experimental data relating to silver have been analysed to determine the stoichiometry of the extracted species. Effect of foreign ions on the extraction of silver was carried out. Recycling capacity of the extractant was also studied. Thiourea and EDTA solutions were found suitable for > 99% stripping of extracted silver(I). The reagent has been found to have high selectivity for silver against copper, cadmium, nickle, cobalt, halfnium, zircomium and europium.

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