Influence of Remaining Acid Sites of an Amorphous Aluminosilicate on the Oligomerization of n-Butenes after Impregnation with Nickel Ions

Highly linear octene isomers can be produced from n-butene on industrial scale by using Ni-containing aluminosilicates as heterogeneous catalysts. These catalysts can be prepared by impregnating an aluminosilicate with a Ni(II) salt solution. This leads to a competition between acid-catalyzed and nickel-catalyzed reactions. In this study it is shown that some octene isomers are exclusively formed via an acid-catalyzed mechanism as a result of methyl group migration at the surface of a mesoporous catalyst. Specifically, the isomers 4,4-dimethylhexene (4,4-DMH) and 3-ethyl-2-methylpentene (3E-2MP) exhibit a systematic correlation compared to the amount of 3,4-dimethylhexene (3,4-DMH) formed at acid sites. By analyzing the ratio of 4,4-DMH and/or 3E-2MP to 3,4-DMH in the product spectrum before and after impregnation with a nickel precursor, the extend of acid site covered by nickel ions can be evaluated.

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Enhancement of HDO Activity of MoP/SiO2 Catalyst in Physical Mixture with Alumina or Zeolites

Catalysts ◽

10.3390/catal10010045 ◽

2019 ◽

Vol 10 (1) ◽

pp. 45 ◽

Cited By ~ 3

Author(s):

Ivan V. Shamanaev ◽

Irina V. Deliy ◽

Evgeny Yu. Gerasimov ◽

Vera P. Pakharukova ◽

Galina A. Bukhtiyarova

Keyword(s):

Catalytic Properties ◽

Acid Sites ◽

Physical Mixture ◽

Reaction Route ◽

Zeolite Β ◽

Acid Catalyzed ◽

Catalyzed Reactions ◽

Metal Catalyzed ◽

High Level ◽

Xrd And Tem

Catalytic properties of physical mixture of MoP/SiO2 catalyst with SiC, γ-Al2O3, SAPO-11 and zeolite β have been compared in hydrodeoxygenation of methyl palmitate (MP). MoP/SiO2 catalyst (11.5 wt% of Mo, Mo/P = 1) was synthesized using TPR method and characterized with N2 physisorption, elemental analysis, H2-TPR, XRD and TEM. Trickle-bed reactor was used for catalytic properties investigation at hydrogen pressure of 3 MPa, and 290 °C. The conversions of MP and overall oxygen-containing compounds have been increased significantly (from 59 to about 100%) when γ-Al2O3 or zeolite materials were used instead of inert SiC. MP can be converted to palmitic acid through acid-catalyzed hydrolysis along with metal-catalyzed hydrogenolysis, and as a consequence the addition of material possessing acid sites to MoP/SiO2 catalyst could lead to acceleration of MP hydrodeoxygenation through acid-catalyzed reactions. Isomerization and cracking of alkane were observed over the physical mixture of MoP/SiO2 with zeolites, but the selectivity of MP conversion trough the HDO reaction route is remained on the high level exceeding 90%.

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Enhancemen Effect of Hydrogen Sulfide Over Metal Ion-Exchange Mesoporous Silicate FSM-16 for Acid Catalyzed Reactions.

ASEAN Journal of Chemical Engineering ◽

10.22146/ajche.50166 ◽

2005 ◽

Vol 5 (1) ◽

pp. 76

Author(s):

Lebong Andalaluna ◽

Masatoshi Sugioka

Keyword(s):

Hydrogen Sulfide ◽

Ion Exchange ◽

Metal Ion ◽

Acid Sites ◽

Enhancement Effect ◽

Mesoporous Silicate ◽

Acid Catalyzed ◽

Activity Enhancement ◽

Catalyzed Reactions ◽

Metal Ion Exchange

The activity enhancement of metal ion-exchange mesoporous silicate FSM-16 (MeFSM-16) by sulfiding with hydrogen sulfide was studied using acid-catalyzed reactions, isomerization of I-butene, cis-2-butene and cyclopropane, as model reactions. It was revealed that the catalytic activities of MeFSM-16 for the acid-catalyzed reactions were remarkably enhanced after sulfiding with hydrogen sulfide. Moreover, it was observed that the optimum enhancement effect of hydrogen sulfide was obtained at the sulfiding temperature of 200°C. Infrared spectroscopic measurement of pyridine adsorption over sulfided MeFSM-16 showed that the activity enhancement of MeFSM-16 resulted in the generation of new Bronsted acid sites. Keywords: Metal ion-exchange, mesoporous silicate, hydrogen sulfide, and activity enhancement.

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Catalytic Properties of Fluorine Modified SmNa-Y Zeolites

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19920781 ◽

1992 ◽

Vol 57 (4) ◽

pp. 781-787 ◽

Cited By ~ 3

Author(s):

Stanisłav Kowalak ◽

Maria Pawłowska ◽

Kenneth J. Balkus

Keyword(s):

Catalytic Properties ◽

Acid Sites ◽

Y Zeolites ◽

Cumene Cracking ◽

Toluene Disproportionation ◽

Zeolite Nay ◽

Polyvalent Cations ◽

Protonic Acid ◽

Acid Catalyzed ◽

Catalyzed Reactions

It is known that mild fluorination of zeolites, including those modified with polyvalent cations, increases their activity for acid catalyzed reactions. In this study we report the reactivity of fluorine modified Sm(III) exchanged zeolite NaY. Mild fluorination of SmNaY reduces the activity of strong protonic acid sites and increases the contribution of weak aprotic acid centres. Results for cumene cracking and toluene disproportionation as well as for 1-hexene isomerization are reported.

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Design and Synthesis of Hyperbranched Aromatic Polymers for Catalysis

Polymers ◽

10.3390/polym10121344 ◽

2018 ◽

Vol 10 (12) ◽

pp. 1344 ◽

Cited By ~ 4

Author(s):

Yuta Nabae ◽

Masa-aki Kakimoto

Keyword(s):

Heterogeneous Catalysts ◽

Aerobic Oxidation ◽

Review Article ◽

Linear Polymers ◽

Design And Synthesis ◽

Oxidation Of Alcohols ◽

Aromatic Polymers ◽

Acid Catalyzed ◽

Ether Ketone ◽

Catalyzed Reactions

Aromatic polymers such as poly(ether sulfone), poly(ether ketone), and polyimide have been widely used in industry due to their thermal, mechanical, and chemical stabilities. Although their application to catalysis has been limited, the introduction of a hyperbranched architecture to such aromatic polymers is effective in developing catalytic materials that combine the advantages of homogenous and heterogeneous catalysts. This review article overviews the recent progress on the design and synthesis of hyperbranched aromatic polymers. Several acid catalyzed reactions and the aerobic oxidation of alcohols have been demonstrated using hyperbranched aromatic polymers as catalysts. The advantage of hyperbranched polymers against linear polymers is also discussed.

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Participation of molecular hydrogen-originated protonic acid sites in acid-catalyzed reactions

Research on Chemical Intermediates ◽

10.1163/156856798x00483 ◽

1998 ◽

Vol 24 (4) ◽

pp. 439-448 ◽

Cited By ~ 5

Author(s):

Hideshi Hattori ◽

Takayuki Yamada ◽

Tetsuya Shishido

Keyword(s):

Molecular Hydrogen ◽

Acid Sites ◽

Protonic Acid ◽

Acid Catalyzed ◽

Catalyzed Reactions

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A Review on Application of Heterogeneous Catalyst in the Production of Biodiesel from Vegetable Oils

Journal of Applied Science & Process Engineering ◽

10.33736/jaspe.432.2017 ◽

2017 ◽

Vol 4 (2) ◽

pp. 142-157 ◽

Cited By ~ 11

Author(s):

A.S. Yusuff ◽

O.D. Adeniyi ◽

M.A. Olutoye ◽

U.G. Akpan

Keyword(s):

Heterogeneous Catalyst ◽

Heterogeneous Catalysts ◽

Biodiesel Production ◽

Comprehensive Overview ◽

Solid Catalysts ◽

Heterogeneous Catalytic ◽

Catalytic Materials ◽

Before And After ◽

Catalyzed Reactions

Biodiesel has been considered as one of the interesting alternative and environmentally benign fuels. The development of environmental friendly heterogeneous catalyst for the esterification/transesterification process seems to be promising route and the reason why it is more preferred to conventional homogeneous and enzymatic catalyzed reactions is discussed. However, investigation on heterogeneous catalyst for biodiesel production is extensively carried out based on previous research studies. In order to reduce cost of biodiesel production, evaluation and characterization of heterogeneous catalytic materials before and after its preparation provide facts on the process that have significant impact on the desired activity and selectivity properties. This review study provides a comprehensive overview of common process techniques usually employ in producing biodiesel. Different materials that serve as sources of heterogeneous catalysts to transesterify oils or fats for production of biodiesel with emphasis on selection criteria of solid catalytic materials are also highlighted. The potential heterogeneous catalyst that could be derived from anthill, various methods of preparing solid catalysts, as well as reusability and leaching analysis are discussed in details

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Exploring the catalytic performance of a series of bimetallic MIL-100(Fe, Ni) MOFs

Journal of Materials Chemistry A ◽

10.1039/c9ta01948k ◽

2019 ◽

Vol 7 (35) ◽

pp. 20285-20292 ◽

Cited By ~ 18

Author(s):

Mónica Giménez-Marqués ◽

Andrea Santiago-Portillo ◽

Sergio Navalón ◽

Mercedes Álvaro ◽

Valérie Briois ◽

...

Keyword(s):

Heterogeneous Catalysts ◽

De Novo ◽

Catalytic Performance ◽

Mixed Metal ◽

Acid Catalyzed ◽

Catalyzed Reactions

Stable mixed-metal FeIII/NiII MIL-100 MOFs have been synthesized de novo and have been explored as superior heterogeneous catalysts in acid catalyzed reactions, presenting superior performances.

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Photoinduced rearrangement of hydroxymethylisoxazolines, a route to enaminoaldehydes

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19862167 ◽

1986 ◽

Vol 51 (10) ◽

pp. 2167-2180 ◽

Cited By ~ 6

Author(s):

Lubor Fišera ◽

Nadezhda D. Kozhina ◽

Peter Oravec ◽

Hans-Joachim Timpe ◽

Ladislav Štibrányi ◽

...

Keyword(s):

Thionyl Chloride ◽

Quantum Yields ◽

Acid Catalyzed ◽

Catalyzed Reactions ◽

Photoinduced Rearrangement ◽

Condensed Heterocycles

3-Aryl-4-R-carbamoyl-5-hydroxymethylisoxazolines (IV) were synthesized by allowing R-NH2 amines with R = H, CH3, C3H7, C6H5C2H5, and NH2 to act on 3-(X-phenyl)-4-oxo-3a,4,6,6a-tetrahydrofuro[3,4-d]isoxazoles (III) with X = H, 4-CH3, 4-OCH3, 2-OCH3, 4-Cl, 2-Cl, 4-F, 2-F, 4-Br, 4-NO2, and 3-NO2. Exposed to radiation, the substances IV give Z-2-hydroxymethylamino-2-aryl-1-formylacrylamides (V) in good yields. The 4-Cl and 4-F substituted Z-derivatives V isomerize irreversibly to the E-derivatives VI if allowed to stand in solvent; the remaining derivatives V are stable. The quantum yields of the photoreaction are from 0.012 to 0.106 in dependence on the substituent X. In all cases where the compounds IV were used for the preparation of condensed heterocycles in conditions of acid-catalyzed reactions, lactones III were preferentially formed; the action of thionyl chloride on IV results in the formation of chloromethyl derivatives VIII, which do not undergo further cyclization.

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Microwaves and Heterogeneous Catalysis: A Review on Selected Catalytic Processes

Catalysts ◽

10.3390/catal10020246 ◽

2020 ◽

Vol 10 (2) ◽

pp. 246 ◽

Cited By ~ 14

Author(s):

Vincenzo Palma ◽

Daniela Barba ◽

Marta Cortese ◽

Marco Martino ◽

Simona Renda ◽

...

Keyword(s):

Heterogeneous Catalysis ◽

Energy Saving ◽

Microwave Heating ◽

Microwave Radiation ◽

Heterogeneous Catalysts ◽

Conventional Heating ◽

Specific Effects ◽

Natural Choice ◽

Future Challenges ◽

Catalyzed Reactions

Since the late 1980s, the scientific community has been attracted to microwave energy as an alternative method of heating, due to the advantages that this technology offers over conventional heating technologies. In fact, differently from these, the microwave heating mechanism is a volumetric process in which heat is generated within the material itself, and, consequently, it can be very rapid and selective. In this way, the microwave-susceptible material can absorb the energy embodied in the microwaves. Application of the microwave heating technique to a chemical process can lead to both a reduction in processing time as well as an increase in the production rate, which is obtained by enhancing the chemical reactions and results in energy saving. The synthesis and sintering of materials by means of microwave radiation has been used for more than 20 years, while, future challenges will be, among others, the development of processes that achieve lower greenhouse gas (e.g., CO2) emissions and discover novel energy-saving catalyzed reactions. A natural choice in such efforts would be the combination of catalysis and microwave radiation. The main aim of this review is to give an overview of microwave applications in the heterogeneous catalysis, including the preparation of catalysts, as well as explore some selected microwave assisted catalytic reactions. The review is divided into three principal topics: (i) introduction to microwave chemistry and microwave materials processing; (ii) description of the loss mechanisms and microwave-specific effects in heterogeneous catalysis; and (iii) applications of microwaves in some selected chemical processes, including the preparation of heterogeneous catalysts.

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