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Catalysts | Free Full-Text | Solventless Mechanochemical ...

Metal-catalyzed oxidation of alcohols to carbonyls is the most considerable fundamental functional-group reactions in organic synthetic chemistry [1,2,3]. The oxidative products are essential raw materials and precursors, which have been extensively utilized in the manufacturing of pharmaceuticals, cosmetics, fragrances, dyes, spices, plastics ...

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Ball Milling Synthesized MnO x as Highly Active Catalyst ...

A rapid (1.5 h) one-step ball milling (BM) method was developed not only to modify commercial MnO2 via top-down approaches (BM0), but also to bottom-up synthesize MnOx by cogrinding of KMnO4 and MnC4H6O4 (BM1) or KMnO4 and MnSO4 (BM2). Catalysts activity on gaseous POPs removal was tested using hexachlorobenzene (HCBz) as surrogate. Catalytic …

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(PDF) Mechanically induced oxidation of alcohols to ...

The present work addresses the development of an eco-friendly and cost-efficient protocol for the oxidation of primary and secondary alcohols to the corresponding aldehydes and ketones by mechanical processing under air. Ball milling was shown to

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Complete Dissolution of Ball-Milled Masson Pine Using an ...

on milling time, but also on the other conditions, such as ball mill model, ball material, and operation frequency. The yields of extractable lignin under specific conditions are more useful than milling time to evaluate the milling intensity (Fujimoto et al. 2005). The yields of extractable lignin and nitrobenzene oxidation products of Masson ...

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oxidation of alcohols - chemguide

oxidation of alcohols This page looks at the oxidation of alcohols using acidified sodium or potassium dichromate(VI) solution. This reaction is used to make aldehydes, ketones and carboxylic acids, and as a way of distinguishing between primary, secondary and …

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Cobalt singled out for selective alcohol oxidation ...

For the oxidation of benzyl alcohols to benzaldehyde, this catalyst demonstrates near perfect performance, with conversion and selectivity figures of 99%. This means that the reaction uses up almost all of the starting material while almost completely avoiding unwanted side-products.

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Catalytic Oxidation of Lignins into the Aromatic Aldehydes ...

3. Oxidation of Lignins into the Aromatic Aldehydes by Nitrobenzene. Oxidation of lignins by nitrobenzene—or nitrobenzene oxidation (NBO)—is a long-known [23,24,25] and highly selective process; its results qualitatively—and even quantitatively—were used to devise the structure of lignins [1,8,22,23,24].The use of nitrobenzene for oxidizing isoeugenol into …

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Supercritical water oxidation of semi-coke wastewater ...

Compared with the single oxidation experiment, which could obtain a residual COD concentration of 603 mg/L at 550 °C, 25 MPa, 1.3 times oxidation coefficient and 120 s, the segmented oxidation, i.e., pre-oxidation stage at 450 °C, 25 MPa, OC = 1.3, t = 60 s and second-stage oxidation at 550 °C, 25 MPa, OC = 0, t = 90 s, realizing a similar ...

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Oxidation of Alcohols - Oxidation of Alcohols to …

In the oxidation test, the alcohols are oxidized with sodium dichromate (Na 2 Cr 2 O 7). The rate of oxidation varies between primary, secondary and tertiary alcohol. On the basis of their oxidation rates, alcohols can be distinguished as: Primary alcohol gets easily oxidized to an aldehyde and can further be oxidized to carboxylic acids too.

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Hydrogen Production by Catalytic Reforming of Gaseous ...

Hydrogen has been attracting great interest as a major energy source in near future. The lack of an infrastructure has led to a research effort to develop fuel processing technology for production of hydrogen. In this review, we are reporting the catalytic reforming of gaseous hydrocarbons carried out in our research group, covering dry-reforming of CH4, tri …

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Ag2O–MnO2/Graphene Oxide Nanocomposite | Encyclopedia

As a conclusion, in general, the current catalytic oxidation protocol has found to be efficacious for oxygenation of various kinds of alcohols include benzylic, aliphatic, allylic, heterocyclic, primary and secondary alcohols, indicating the versatility of Ag 2 O–MnO 2 /(5 wt.%)GRO catalyst for aerial selective alcohol oxidation.

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Oxidation of Alcohol | hzorganichemistry

Oxidation of Alcohol. Oxidising the different types of alcohols. The oxidising agent used in these reactions is normally a solution of sodium or potassium dichromate (VI) acidified with dilute sulphuric acid. If oxidation occurs, the orange solution containing the dichromate (VI) ions is reduced to a green solution containing chromium (III) ions.

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Selective oxidation of alcohols with molecular oxygen ...

Typical procedure for the oxidation of alcoholsA suspension of Ru/MnO x /CeO 2 (0.202 g, 5.0 mol% Ru) in α,α,α-trifluorotoluene (1.5 ml) was stirred for 10 min under O 2 atmosphere. The suspension was heated at 300 K and benzyl alcohol (0.108 g) was then added. The mixture was stirred at 300 K for 90 min under O 2 atmosphere. Benzaldehyde was …

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Original Paper - Taketoshi Minato

Original Paper. Google Scholar. Researchgate. Academia. Publons. "Molecular-Scale Solvation Structures of Ionic Liquids on a Heterogeneously Charged Surface". Kenichi Umeda, Kei Kobayashi, Taketoshi Minato, Hirofumi Yamada. J. Phys. Chem. Lett. 11, 8094-8099 (2020). "Influence of LiBOB as an Electrolyte Additive on the Performance of BiF ...

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Mechanically induced oxidation of alcohols to aldehydes ...

In 2015, Mal et al. reported the first example of a very interesting solvent free ball-milling oxidation of activated primary alcohols to aldehyde using NBS (1.5 equiv) or oxone (0.6 equiv) as co-oxidising agents. This paper has laid the foundation for further studies on this topic. [Google Scholar]

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Formation of Nitriles, Carboxylic ... - Wiley Online Library

For the oxidation of alkenes to 2‐hydroxyalkyl alkanoate esters, see Formation of Alcohols and Phenols by Alkene, Diene, and Alkyne Additions, Section 1. For the electrophilic cyclization of alkenoic acids and alkenamides to lactones and lactams, …

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Cellulose interpolymers and method of oxidation - EASTMAN ...

Oxidation of alcohols with TEMPO under acidic conditions converts primary and secondary alcohols to aldehydes and ketones, respectively (Bobbit, J. M.; Ma, Z., J. Org. Chem. 1991, 56, 6110-6114). Generally, over oxidation is not observed, but two molar equivalents of TEMPO per mole of substrate are required for the oxidation of the alcohol.

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MnOx–CeO2 mixed oxides for diesel soot oxidation: a review ...

The MnO x –CeO 2 exhibits high catalytic activities towards soot oxidation in the presence or absence of NO x. The superior soot oxidation activity of MnO x –CeO 2 in air is attributed to the excess amount of oxygen vacancies which promote the surface oxygen chemisorption. The mobility and replenishment of lattice oxygen are enhanced and ...

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NaOH alone can be a homogeneous ... - ScienceDirect.com

These observations are made on the aerobic oxidation reactions of different alcohols, including GL, ethylene glycol (EG), 2-propanol (2-PO), and ethanol (EtOH) in water under 1.0 MPa oxygen at 60–100 °C in the absence of any solid catalyst. The obtained data also provide a rigorous assessment of the relative reactivity of the different ...

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Photocatalytic Activity of g-C3N4 in the Partial Oxidation ...

The initial g-C 3 N 4 has a luminescence band in 420-600 nm region (Fig. 1a, curve 3) with a maximum at 460 nm, the intensity of which decreases significantly after treatment in the molten salts (Fig. 1a, curve 4).In view of the fact that the luminescence emission is a concurrent process involving expenditure of the photogenerated charges the photocatalytic activity of …

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I. Basic Principles ID. Oxidation Reactions

Oxidation of Activated Alcohols to Aldehydes [MnO 2] P. Wipf - Chem 2320 4 2/4/2006. 5 - Wipf, P.; Kim, Y.; Fritch, P. C. J. Org. Chem. 1993, 58, 7195. ... The rate of oxidation of alcohols by silver carbonate/Celite strongly depends on the solvent and the type of alcohol. More polar solvents and benzene slow the

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Catalysts | Free Full-Text | A Facile Synthesis of ZrOx ...

Catalytic oxidation of alcohols into respective aldehydes and ketones is a pivotal reaction in organic syntheses, because it produces valued precursors in agrochemicals, food processing, confectionary, fragrances, dyestuffs, insecticides, flame-retardants, and pharmaceuticals industries [1,2].Conventionally, alcohol oxidation has relied on the utilization of toxic and …

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Carbon dots-based catalyst for various organic ...

Carbon dots (CDs), owing to their zero-dimensional structure and outstanding physicochemical features, can be used as a support to metals, metal oxides, to form nanocomposites, thus emerging as promising nanocatalysts to drive various organic transformations. For this reason, we planned to review the usage and advantages of these …

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Mechanochemical Synthesis of a Carboxylated Carbon ...

mechanochemical oxidation of activated carbon using persulfate salts as oxidant in a planetary ball mill without using any solvent. In a typical catalyst preparation experiment, a steam activated carbon was milled with the solid oxidizing agent in a planetary ball mill for 5 h. The resulting mixture was washed with 5% HCl

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General and Prospective Views on Oxidation Reactions in ...

The selective oxidation of a broad set of primary and secondary benzyl alcohols to the corresponding aldehydes and ketones has been recently performed at room temperature under solvent-free ball milling conditions with no trace of over-oxidation carboxylic acid products . Under mechanical activation conditions with zirconia milling balls ...

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Highly selective oxidation of alcohols using MnO2/TiO2 ...

MnO 2 /TiO 2-ZrO 2 is an active and environmentally friendly catalyst for liquid phase oxidation of alcohols. With almost identical manganese dioxide loading by adsorption method, MnO 2 /TiO 2-ZrO 2 exhibited better catalytic behaviors than other used catalysts. This catalyst also showed excellent reusability in the process.

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Catalyst Types and Preparation Notes - Chemical Engineering

Few applications of semiconductor catalysts are: CuO for oxidation of nitric oxides, NiO for dehydrogenation of alkanes, MnO 2 for oxidation of alcohols, and V 2 O 5 for oxidation of hydrocarbons. Insulators: Catalytic functions of insulators are different from that of conductor and semi conductor materials.

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Photocatalytic Selective Oxidation of Organic Compounds in ...

The most efficient oxidation was found for allylic alcohols, while the oxidation of alcohols such as cyclohexanol proceeds much more slowly. 3-Pentanol ( t = 10 h, X = 55%, S = ) [ 71 ] and 2-heptanol ( t = 1.5 h, X = 3%, S = ) [72%] are oxidized by molecular oxygen to ketones in the presence of mpg-C 3 N 4 samples by the action of ...

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Oxidation of alcohols - Groby Community College

Alcohols - oxidation. Oxidation reactions do depend on the type of alcohol we have: primary, secondary or tertiary. Primary and secondary alcohols can be oxidised with acidified aqueous potassium dichromate(VI). This reagent will not affect tertiary alcohols. They are . …

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Solvent-free, visible-light photocatalytic alcohol ...

Flavins were studied extensively for the oxidation of alcohols, amines, methylbenzenes, styrenes, and phenylacetic acids [9-12]. Some derivatives were also immobilized on silica ... reaction mixture in ball mills, such as the vibrational ball mill or the planetary ball mill, or with a pestle and mortar. In prelimi-

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Fabrication and charge–discharge properties of composites ...

Ni x Mn 1−x O solid solution were synthesized by mechanical ball-milling and calcination with X = 0.1–0.9 ratio of NiO and MnO. The ball-milling for synthesis of Ni x Mn 1−x O solid solution was performed for 5 h at a rotational speed of 650 rpm in an Ar atmosphere using a planetary ball-milling apparatus (P-7; Fritsch Japan Co., Ltd,). A ZrO 2 crucible (volume of 30 …

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Reactions of Alcohols - Rutgers University

Oxidation of Primary Alcohols Primary alcohols are easily oxidized just like secondary alcohols, and the INITIAL product of oxidation is an aldehyde. Ch11 Reacns of Alcohols (landscape).docx Page 4 However, the aldehyde can also be easily oxidized to an acid, and this 'over-oxidation' is a practical problem.

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Angewandte Chemie International Edition: Vol 52, No 48

It contains a framework of MnO 4 tetrahedra ... The alkoxyamine exhibits a high catalytic activity for the oxidation of alcohols to afford the corresponding carbonyl compounds in high yield by oxidative transformation into an oxoammonium ion, which is proposed to serve as an active species. ... the rate of a ball-mill reaction catalyzed by Cr 2 ...

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Mechanochemical catalytic oxidations in the solid state ...

The oxidation of primary alcohols under mechanochemical conditions in a Spex8000M Mixer/Mill was investigated. To facilitate ease of separation and recyclability, a …

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The preparation of large surface area lanthanum based ...

In addition to the SAS preparation method, LaMnO 3 was synthesised by mechanochemical milling of the individual oxides and flame spray pyrolysis. The milling procedure used a planetary ball mill (Retsch PM100). La 2 O 3 and Mn 2 O 3 were added to a ZrO 2 milling vessel with six 15 mm ZrO 2 balls before being ground at 700 rpm for 16 h. The resulting dry …