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Heterogeneous catalysts

Tìm thấy 16+ kết quả cho từ khóa "Heterogeneous catalysts"

Ranolazine-functionalized CuO NPs: Efficient homogeneous and heterogeneous catalysts for reduction of 4-nitrophenol

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The catalytic process for heterogeneous catalysis is not more effective as in the case of homogeneous catalysis because several active sites of CuO NPs were blocked due to their attachment to glass strips. However, the advantage of heterogeneous catalysis is that CuO NPs can be reused as catalysts for several cycles. These CuO NPs are highly economical and nontoxic, with excellent efficiency for catalytic reduction of 4-NP in both homogeneous and heterogeneous media..

Reusability and regeneration of solid catalysts used in ultrasound assisted biodiesel production

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Ultrasonic-assisted biodiesel production process from palm oil using alkaline earth metal oxides as the heterogeneous catalysts. doi: 10.1016/j.apcatb . doi: 10.1016/j.saa . doi: 10.1016/j.jece . Wang R, Li H, Chang F, Luo J, Hanna MA et al. A facile, low-cost route for the preparation of calcined porous calcite and dolomite and their application as heterogeneous catalysts in biodiesel production. doi: 10.1039/

Synthesis and application of polyvinylimidazole-based Brønsted acidic ionic liquid grafted silica as an efficient heterogeneous catalyst in the preparation of quinoxaline derivatives

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As an extension of our previous work on heterogeneous catalysts based on polymeric support and polymer grafted silica, 46 − 52 herein we report the synthesis and characterization of two types of polyvinylimidazole-based Brønsted acidic ionic liquid grafted silica and their application as heterogeneous catalysts in the synthesis of quinoxaline derivatives with various substrates. The quinoxaline derivatives are important precursors in pharmaceutical chemistry..

The promoted synthesis of minoxidil by magnetic nanoparticles of cobalt ferrite (CoFe2O4) as a heterogeneous reusable catalyst

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The prepared nanoferrites were utilized as efficient and green heterogeneous catalysts for N -oxidation of 2,6-diamino-4- chloro-pyrimidine with H 2 O 2 in refluxing ethanol giving 2,6-diamino-4-chloro-pyrimidine N -oxide as a starting material for the synthesis of 2,4-diamino-6-piperidinopyrimidine 3-oxide (minoxidil). Recently, magnetic nanoparticles of ferrites have been widely used as green and efficient heterogeneous catalysts in the synthesis of organic compounds.

Study on the SiO2 supported ionic liquid phase (SILP) catalysts for the hydroformylation of ethylene

240970-ND.pdf

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Catalysts for hydroformylation reaction 11 1.1.4. Recent trends in the heterogeneous hydroformylation reaction 14 1.1.5. Heterogeneous catalysts for vapor phase hydroformylation of alkenes 17 1.1.6 Mechanism of hydroformylation reaction 21 1.2. SILP catalyst 26 1.2.1.

Selective oxidation of sulfides and hydrocarbons with H2O2 over manganese catalyst supported on nanoparticles

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Comparison of the homogeneous and heterogeneous systems reveals that the heterogeneous catalysts exhibited lower activity than the homogeneous catalyst (Table 8, entries 1–3). Various homogeneous and heterogeneous Mn catalysts have been used for the oxidation of cycloalkanes with H 2 O 2 and t-BuOOH. 47,48 However, none of the reported catalysts showed such high activity and/or selectivity as [Mn 2 (HL) 2 (H 2 O) 4 ] or Fe 3 O 4 @SiO 2 /[Mn 2 L(HL)(H 2 O) 4.

Hydrotalcite framework stabilized ruthenium nanoparticles (Ru/HTaL): Efficient heterogeneous catalyst for the methanolysis of ammonia-borane

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In this study, hydrotalcite framework stabilized ruthenium nanoparticles were prepared, characterized, and used as heterogeneous catalysts in the methanolysis of AB. The characterization of the resulting Ru/HTaL material was done by using various spectroscopic and visualization techniques, which showed the formation of highly dispersed and crystalline ruthenium(0) nanoparticles with a mean diameter of 1.27 ±0.8 nm on the surface of HTaL,.

Acid-activated clay as heterogeneous and reusable catalyst for the synthesis of bioactive cyclic ketal derivatives

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Moreover, heterogeneous catalysts often avoid the contamination of the final product, which is essential for further implementation in the pharmaceutical market. 25 Ion exchange resins such as niobium phosphate have been evaluated in the acetalization of hexanal under mild reaction conditions.

Heterogeneous Fenton-like degradation of Acid Red 17 using Fe-impregnated nanoporous clinoptilolite: artificial neural network modeling and phytotoxicological studies

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The degradation efficiency of AR17 by the Fenton-like process with NP-Clin and Fe-NP-Clin as heterogeneous catalysts was 43.5% and 97.6%, respectively. Therefore, Fe-NP-Clin was selected as a heterogeneous catalyst for further experiments.. Decolorization efficiency of AR17 in different oxidation processes (a): Heterogeneous Fenton with Fe-NP- Clin. (b): Heterogeneous Fenton with NP-Clin. (c) Adsorption onto Fe-NP-Clin sample.

Advances in polymer based Friedlander quinoline synthesis

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Friedländer synthesis of poly-substituted quinolines using a highly efficient and reusable heterogeneous catalyst. Titania nanomaterials: Efficient and recyclable heterogeneous catalysts for the solvent-free synthesis of poly-substituted quinolines via Friedlander hetero-annulation. A mild and highly efficient Friedländer synthesis of quinolines in the presence of heterogeneous solid acid nano-catalyst.

Encapsulation of copper(II) complexes with three dentate NO2 ligands derived from 2,6-pyridinedicarboxylic acid in NaY zeolite

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Furthermore, our homogeneous and heterogeneous catalysts are very efficient compared to [Cu(H 4 C 6 N 6 S 2 ) ]–NaY 31 in the oxidation of cyclohexene. In addition, the catalyst and method applied in this paper have advantages in terms of heterogeneous nature, high reusability, high conversions, and selectivity of the catalyst.. Comparison of literature catalysts and our catalyst system for oxidation of hydrocarbons.. 1 Cu–salen 28.

Efficient C–C cross-coupling reactions by (isatin)-Schiff base functionalized magnetic nanoparticle-supported Cu(II) acetate as a magnetically recoverable catalyst

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Comparison of the catalytic activity of various heterogeneous catalysts in the Suzuki–Miyaura cross-coupling reaction.. 1 Fe 3 O 4 @SiO 2 –Isa Cu(II) 70 92 a This work. Metal existence, phase purity, and crystallinity of the sample were characterized by XRD using a Philips X’Pert MPD with Cu K α radiation.

Catalytic conversion of carbon dioxide into cyclic carbonates by Cu(II) and Ni(II) acetylacetonates anchored onto Siral 80

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In the present study, heterogeneous catalysts were prepared by using Siral 80 as a support material, APTES as a modifier, and Cu(acac) 2 or Ni(acac) 2 as metal acetylacetonates according to the procedure explained above, and characterized. Siral 80 was obtained from SASOL-Condea AG, Germany. The chemical composition of Siral 80 is 78.3% SiO 2 , 21.7% Al 2 O 3 , 0.02% Fe 2 O 3 , 0.02% TiO 2 , 0.01% CaO, and 0.2% MgO. Preparation of the catalysts.

Exploration of efficiency of nano calcium oxide (CAO) as catalyst for enhancement of biodiesel production

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Inorganic heterogeneous catalysts offer abundant benefits relative to either inorganic homogenous or organic catalyst including ease of separation, recovery of catalyst, reusability of catalyst, cheap and minimized corrosion (Mazaheri et al., 2018. Bhuyar et al., 2019).. Among the heterogeneous catalyst that was used in transesterification reaction, calcium oxide, CaO proven to be highly effective catalyst in biodiesel production by many literature studies.

BẢNG TÓM TẮT ĐỀ TÀI NGHIÊN CỨU "Nghiên Cứu Tổng Hợp Họ Vật Liệu MOF-Cu và Khảo Sát Hoạt Tính

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Dhakshinamoorthy, A., et al., Delineating similarities and dissimilarities in the use of metal organic frameworks and zeolites as heterogeneous catalysts for organic reactions. Yaghi, The pervasive chemistry of metal-organic frameworks. Garcia, Metal organic frameworks as efficient heterogeneous catalysts for the oxidation of benzylic compounds with t- butylhydroperoxide. Kuppler, R.J., et al., Potential applications of metal-organic frameworks.

Green dehydrogenation of dimethylamine borane catalyzed by cheaply copper(0) nanocatalysts without any stabilizer at nearly room temperature

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Dimethylammonium hexanoate stabilized rhodium(0) nanoclusters identified as true heterogeneous catalysts with the highest observed activity in the dehydrogenation of dimethylamine-borane. Thermal dehydrogenation of dimethylamine borane catalyzed by a bifunctional rhenium complex. Aminopropyltriethoxysilane stabilized ruthenium(0) nanoclusters as an isolable and reusable heterogeneous catalyst for the dehydrogenation of dimethylamine–borane.

Tin-sulfur based catalysts for acetylene hydrochlorination

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Development of a heterogeneous non-mercury catalyst for acetylene hydrochlorination.. doi: 10.1021/acscatal.5b01178. doi: 10.1162/GLEP_a_00208. doi: 10.5194/acp . doi: 10.1126/. doi: 10.1021/jacs.5b07752. doi: 10.1016/j.jcat . doi: 10.1021/acscentsci.8b00306. doi: 10.1126/science.aal3439. doi.org/10.1039/C7CC05986H. doi.org/10.1039/C5CY00751H. doi: 10.1039/C8CY00291F. doi: 10.1039/C9CY00401G. doi: 10.1016/J.MCAT .

Sn(II)/PN@AC catalysts: Synthesis, physical-chemical characterization, and applications

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High performance of supported Cu-based catalysts modulated via phosphamide coordination in acetylene hydrochlorination. doi: 10.1016/j.apcata . The Preparation of Cu-g-C 3 N 4 /AC catalyst for acetylene hydrochlorination. doi: 10.3390/. MOMTPPC improved Cu-based heterogeneous catalyst with high efficiency for acetylene hydrochlorination. doi: 10.1016/j.mcat . doi: 10.1039/C3RA46099A.

Oxidative dehydrogenation of propane over V2O5 and K2O-V2O5 impregnated MgAl2O4 catalysts

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Heterogeneous catalyst design for petrochemical selective oxidation reactions is a fundamental research field in catalysis, and oxidative dehydrogenation (ODH) of propane has gained great importance for lower alkane utilization in recent years. 1,2 Endothermic direct dehydrogenation of propane is an equilibrium reaction. thus its conversion is temperature limited, the enthalpy of the reaction is high, and catalyst coking is commonly observed.

Photocatalytic decomposition of textile dyestuffs by photosensitive metal oxide catalysts

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The heterogeneous photocatalytic oxidation method included in the IOP enables the transformation of pollutants into harmless and/or less harmful components by degradation of pollutants in the presence of UV light and semiconductor metal oxides (ZnO, TiO 2 , CeO . In this study, photodegradation of dyes with Bi 2 O 3 -CTAB and ZnO-CTAB catalysts was examined. Abstract: Textile azo dyes are one of the pollutants in waste water that adversely affect human and environmental health.