Acetone

About: Acetone is a research topic. Over the lifetime, 9458 publications have been published within this topic receiving 120867 citations. The topic is also known as: propanone & dimethylketone.

A new one-pot hydrothermal synthesis and electrochemical characterization of Li1+xMn2−yO4 spinel structured compounds

Abstract: A simple one step hydrothermal route to Li1+xMn2−yO4 spinel compounds (x = 0.01–0.06, y = 0.02–0.09) via reduction of commercially available potassium permanganate with common organic reductants (alcohols, acetone, hex-1-ene, and isobutyraldehyde) in lithium hydroxide aqueous solutions is developed. The cubic spinel phase with no other impurities can be isolated after short reaction times (∼5 h) at the relatively low temperature of 180 °C. Scanning electron microscopy imaging reveals that the crystalline products have a distribution of sizes; the majority of the sample is composed of smaller particles between 10 and 30 nm. However, there are noticeably larger 100–300 nm interspersed particles—more prevalent in reactions with acetone and isobutyraldehyde. In corresponding benchtop test reactions, UV-Vis spectroscopy shows that the disappearance of MnO4− occurs more rapidly when acetone and isobutyraldehyde are used as reducing agents. Cyclic voltammetry performed on our spinels prepared via hydrothermal synthesis shows three reversible redox processes: a wave with E1/2 of ∼2.9 V (vs. Li/Li+) and two close waves between 4.05 and 4.15 V. Galvanostatic cycling of a cell composed of Li1.02Mn1.96O4 prepared from the oxidation of acetone between 3.5 and 4.4 V demonstrates a specific capacity of 104 mA h g−1 on first discharge, with ∼87% capacity retention (90 mA h g−1) after 100 cycles. The specific capacity of all samples correlates with the rate of disappearance of MnO4− observed in our benchtop reactions, providing a facile way to control particle size and electrochemical behavior.

Infrared study of the adsorption of acetone on rutile

Abstract: The associative adsorption of acetone onto Lewis acidic Ti4+ ion sites on rutile is followed by the formation of a surface enolate complex which reacts with a further acetone molecule to give mesityl oxide. The enolate is also an intermediate in the exchange of hydrogen atoms between acetone and hydroxyl groups on rutile. The effects of dehydroxylation and dehydration of the rutile surface on the associative adsorption of acetone and on the formation of the enolate complex and mesityl oxide have been studied using infrared spectroscopy. The reversibility of the surface reactions has been established, in part by a study of the adsorption of mesityl oxide, which not only associatively adsorbs onto Ti4+ ion sites but also decomposes to enolate complex and coordinatively liganded acetone molecules. Reduction of rutile in hydrogen decreases the Lewis acidity of the oxide surface but promotes the formation of surface acetate ion by the chemisorption of acetone.

Mechanisms for hydrogenation of acetone to isopropanol and of carbon oxides to methanol over copper-containing oxide catalysts

Abstract: Mechanisms for the synthesis of methanol from CO and CO2 and for the hydrogenation of acetone to isopropanol are discussed based on the recent experimental results obtained by the authors. The state of copper-containing compounds in a hydrogen medium at 200–400°C and the nature of their interaction with the reaction components were studied. Hydrogenation of carbon oxides and acetone was proposed to be the result of the ability of copper ions to reversible transformations to generate copper metal and protons. Activation of acetone and CO2 can be achieved through their interaction with Cu0, and activation of CO through its interaction with oxygen-containing sites of Cu+1OCu+1 type which are formed after oxidation of a portion of Cu0 with carbon dioxide.

Antioxidative effects of the acetone fraction and vanillic acid from Chenopodium murale on tomato plants

Abstract: From the active acetone fraction of Chenopodium murale, vanillic acid was isolated and identified, based on 1H and 13C nuclear magnetic resonance spectral analyses. Free phenolic compounds inside the active acetone were qualified and quantified by using high performance liquid chromatography analysis, which revealed the presence of seven compounds with an abundance of vanillic and p-hydroxybenzoic acids. The allelopathic potential of the acetone fraction and vanillic acid was evaluated through laboratory bioassays against tomato plants. Our results showed that the allelopathic potential induced by low concentrations of the acetone fraction and vanillic acid stimulated the germination and growth of tomato and had stimulating effects on the activity of some antioxidant enzymes. We observed an enhancement in the activity of catalase, peroxidase, superoxide dismutase, and polyphenol oxidase, as well as the content of soluble protein and phenolic glycoside. Meanwhile, the levels of free phenolic compounds, H2O2, and lipid peroxidation decreased. The highest stimulations were recorded at 50 p.p.m. of acetone fraction and 0.5 p.p.m. of vanillic acid. In contrast, the highest concentrations exerted negative effects on all the measured parameters to record the maximum value of inhibition at 400 p.p.m. of acetone fraction and 4 p.p.m. of vanillic acid. These results proved the antioxidative effects of active acetone and vanillic acid at low concentrations and their potent use as a stimulator for tomato germination and growth.