- Stability of hydrogen peroxide during perhydrolysis of carboxylic acids on acidic heterogeneous catalysts
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This paper describes a study of the stability of hydrogen peroxide in the presence of different aluminosilicate materials, in connection with an investigation of carboxylic acid perhydrolysis. During the reaction, aluminosilicate materials such as H-β zeolites, mesoporous material H-MCM-41 and alumina initiate the decomposition of hydrogen peroxide. The reason of the spontaneous decomposition of H2O2 is related to the partial dealumination of these zeolites. However, in the case of experiments carried out with H-ZSM-5 zeolite catalysts, a slight catalytic effect on the perhydrolysis and no spontaneous decomposition of hydrogen peroxide were noticed. The use of cation exchange resins as catalysts is more kinetically beneficial than H-ZSM-5 zeolite catalysts. Springer Science+Business Media B.V. 2010.
- Leveneur, Sebastien,Kumar, Narendra,Salmi, Tapio,Murzin, Dmitry Yu.
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Read Online
- Method for preparing peroxypropionic acid
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The invention relates to a method for preparing peroxypropionic acid. The method comprises the following step: performing a contact reaction on propionic acid and an oxidizing agent in the presence ofa catalyst, wherein the catalyst is a titanium silicon aluminum molecular sieve catalyst. The method provided by the invention has a simple process, a high conversion rate of propionic acid, good selectivity of the product peroxypropionic acid, and a production process easy to control, and is suitable for flexible production on various scales.
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Paragraph 0103-0132
(2019/08/30)
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- Branching ratios for the reaction of selected carbonyl-containing peroxy radicals with hydroperoxy radicals
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An important chemical sink for organic peroxy radicals (RO2) in the troposphere is reaction with hydroperoxy radicals (HO2). Although this reaction is typically assumed to form hydroperoxides as the major products (R1a), acetyl peroxy radicals and acetonyl peroxy radicals have been shown to undergo other reactions (R1b) and (R1c) with substantial branching ratios: RO2 + HO2 → ROOH + O2 (R1a), RO 2 + HO2 → ROH + O3 (R1b), RO2 + HO2 → RO + OH + O2 (R1c). Theoretical work suggests that reactions (R1b) and (R1c) may be a general feature of acyl peroxy and α-carbonyl peroxy radicals. In this work, branching ratios for R1a-R1c were derived for six carbonyl-containing peroxy radicals: C2H 5C(O)O2, C3H7C(O)O2, CH3C(O)CH2O2, CH3C(O)CH(O 2)CH3, CH2ClCH(O2)C(O)CH 3, and CH2ClC(CH3)(O2)CHO. Branching ratios for reactions of Cl-atoms with butanal, butanone, methacrolein, and methyl vinyl ketone were also measured as a part of this work. Product yields were determined using a combination of long path Fourier transform infrared spectroscopy, high performance liquid chromatography with fluorescence detection, gas chromatography with flame ionization detection, and gas chromatography-mass spectrometry. The following branching ratios were determined: C2H5C(O)O2, YR1a = 0.35 ± 0.1, YR1b = 0.25 ± 0.1, and YR1c = 0.4 ± 0.1; C3H7C(O)O2, YR1a = 0.24 ± 0.15, YR1b = 0.29 ± 0.1, and YR1c = 0.47 ± 0.15; CH3C(O)CH2O2, Y R1a = 0.75 ± 0.13, YR1b = 0, and YR1c = 0.25 ± 0.13; CH3C(O)CH(O2)CH3, Y R1a = 0.42 ± 0.1, YR1b = 0, and YR1c = 0.58 ± 0.1; CH2ClC(CH3)(O2)CHO, Y R1a = 0.2 ± 0.2, YR1b = 0, and YR1c = 0.8 ± 0.2; and CH2ClCH(O2)C(O)CH3, YR1a = 0.2 ± 0.1, YR1b = 0, and YR1c = 0.8 ± 0.2. The results give insights into possible mechanisms for cycling of OH radicals in the atmosphere.
- Hasson, Alam S.,Tyndall, Geoffrey S.,Orlando, John J.,Singh, Sukhdeep,Hernandez, Samuel Q.,Campbell, Sean,Ibarra, Yesenia
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experimental part
p. 6264 - 6281
(2012/08/28)
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- Perhydrolase
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The present invention provides methods and compositions comprising at least one perhydrolase enzyme for cleaning and other applications. In some particularly preferred embodiments, the present invention provides methods and compositions for generation of peracids. The present invention finds particular use in applications involving cleaning, bleaching and disinfecting.
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Page/Page column 51-53
(2008/12/06)
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- Peracid precursors for antimicrobial use
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This disclosure describes unique chemical structures for use as solid or concentrated chemical precursors to the production of peroxy acids when combined with hydrogen peroxide or a hydrogen peroxide precursor such as percarbonates or perborates. Peroxy acids (peracids) such as peroxyacetic acid are used currently to disinfect medical equipment such as endoscopes and related items. It has been discovered that these structures are not currently listed in Chemical Abstracts and do not appear to be the subject of any prior art related to this or any other similar application. The specification for this claim includes chemical structures for each claimed precursor as well as means of synthesis that could be carried our by any skilled synthetic organic chemist. Practical uses for this invention include several antimicrobial applications of which at least one example is included.
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Page/Page column 5
(2008/06/13)
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- HIGH-PURITY ALICYCLIC EPOXY COMPOUND, PROCESS FOR PRODUCING THE SAME, CURABLE EPOXY RESIN COMPOSITION, CURED ARTICLE THEREOF, AND USE
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The present invention provides a high-purity alicyclic epoxy compound in which an alicyclic olefin compound is epoxidized with an aliphatic percarboxylic acid having substantially no water followed by the removal of a solvent to produce an alicyclic epoxy compound represented by the general formula (I) that is in turn subjected to purification by distillation to thereby the high-purity alicyclic epoxy compound wherein the concentration of high-molecular-weight components having an elution time shorter than that of the alicyclic epoxy compound in detection by a GPC analysis is 5.5% or less in terms of the area ratio, the concentration of impurities having a retention time shorter than that of the alicyclic epoxy compound in detection by a GC analysis is 19.5% or less in terms of the area ratio, the concentration of reactive intermediates is 4.5% or less in terms of the area ratio, and a color hue (APHA) is 60 or less; a process of efficiently producing the same by the use of a low-toxicity solvent; a curable resin composition using the same; a cured product; and applications.
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Page/Page column 16
(2010/11/24)
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- PROCESS FOR PRODUCING EPOXY COMPOUND, EPOXY RESIN COMPOSITION AND USE THEREOF, ULTRAVIOLET-CURABLE CAN COATING COMPOSITION, AND PROCESS FOR PRODUCING COATED METAL CAN
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The invention I provides a method of producing an alicyclic epoxy compound having a specific structure, which comprises epoxidizing an alicyclic olefin compound having a specific structure by using an aliphatic percarboxylic acid having low water content. The alicyclic epoxy compound is useful for use in coatings, inks, adhesives, sealants, encapsulants, stabilizers or the like. The invention II provides an epoxy resin composition containing the alicyclic epoxy compound as a main component, and a photosemiconductor device comprising a photosemiconductor element encapsulated with the epoxy resin composition. The epoxy resin composition can be cured by heating, thereby obtaining a cured product having excellent moisture and heat resistance and transparency. The invention III provides: an ultraviolet rays-curable can-coating composition containing the alicyclic epoxy compound as a main component, which can be cured by ultraviolet irradiation, and can form a coating film having excellent film performances such as processability, adhesion, hardness and scratch resistance, particularly film appearance and retort resistance; and a process of producing a coated metal can using the composition.
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- Method for preparing β-phosphorous nitroxide radicals
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The invention concerns a method for preparing β-phosphorous nitroxide radicals which comprises preparing in a first step an aminophosphonate by reacting a carbonyl compound, a primary amine and a phosphorous compound, then in a second step in oxidizing said aminophosphonate using on-halogenated organic peracids in a two-phase organic water/solvent medium with a buffered aqueous phase with a pH ranging between 5 and 12.
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- Heterolytic decarboxylation involving acyltrifluoroacetyl peroxide intermediates
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Selective carboxylic acid decarboxylation was elaborated. Generation of acyltrifluoroacetyl peroxides from carboxylic peracids and trifluoroacetyl anhydride (Method A), as well as from trifluoroperacetic acid and acyltrifluoroacetyl anhydride (Method B), leads to simultaneous peroxide decomposition into the corresponding alkyltrifluoroacetates. DFT computations, as well as experimental data, support an acid-catalyzed heterolytic mechanism for acyltrifluoroacetyl peroxide decomposition.
- Krasutsky, Pavel A.,Kolomitsyn, Igor V.,Botov, Evgenij M.,Carlson, Robert M.,Semenova, Irina G.,Fokin, Andrey A.
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p. 8687 - 8691
(2007/10/03)
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- PROCESS FOR PREPARING EQUILIBRIUM PEROXY ACID AND PROCESS FOR PRODUCING LACTONE
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The present invention relates to a method of producing an equilibrium peracid mixture containing not more than 1.5% by weight of water and not more than 1.5% by weight of hydrogen peroxide by reacting hydrogen peroxide and carboxylic acid(s) in a reaction-distillation apparatus while removing water. The present invention also relates to the reaction between the above-mentioned equilibrium peracid mixture and a cyclic ketone. According to the method of the present invention, the selectivity to the lactone can be increased without any decrease of the initial reactivity in the conversion of the cyclic ketone.
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- Liquid chromatographic simultaneous determination of peroxycarboxylic acids using postcolumn derivatization
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The first liquid chromatographic method with postcolumn derivatization for the simultaneous determination of peroxycarboxylic acids is described. Aliphatic peracids with chain lengths from C2 to C12 are separated by HPLC on a reversed-phase C18 column with acetonitrile/water gradient elution. For improved peak shape, tetrahydrofuran and acetic acid are added to the aqueous eluent. After chromatographic separation, the peroxycarboxylic acids react with 2,2′-azino-bis(3-ethylbenzothiazoline)-6-sulfonate, a popular substrate for the enzyme peroxidase. Iodide traces are added as catalyst. The oxidation product, a green radical cation, is determined using a UV/ visible detector in four characteristic regions of the visible and near-infrared spectrum in the range 405-815 nm. The advantages of the new method are detection limits in the low micromolar range, negligible matrix interferences, high reproducibility, and the possibility for simultaneous determination of several peroxycarboxylic acids.
- Effkemann,Pinkernell,Neumueller,Schwan,Engelhardt,Karst
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p. 3857 - 3862
(2007/10/03)
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- Process for preparing perpropionic acid solution
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A process for preparing perpropionic acid solution comprising reacting propionic acid with hydrogen peroxide in the presence of a boric acid catalyst wherein the reaction is carried out by using an ethyl propionate as a reaction solvent, and water in the reaction solution is removed continuously by azeotropic distillation with the reaction solvent. Since the reaction is carried out while the concentration of the peroxide in an aqueous phase separated from the distillate by the azeotropic distillation is maintained at not more than 0.1% by weight, a perpropionic acid solution containing almost no unreacted hydrogen peroxide can be prepared.
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- Process for stabilizing percarboxylic acid
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Disclosed is a process for stabilizing a percarboxylic acid characterized in that the percarboxylic acid is mixed with at least one pyridine derivative selected from the group consisting of picoline, ethylpyridine, conyrine, lutidine and N-oxide thereof.
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- Process for the preparation of epsilon-caprolactone
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Process for manufacturing Σ- caprolactone by oxidation of cyclohexanone by means of a crude C2 -C4 percarboxylic acid solution, resulting from the reaction of hydrogen peroxide on the corresponding carboxylic acid in the presence of a weak acid catalyst, with continuous elimination of water by azeotropic entrainment, characterized in that the molar ratio of cyclohexanone used to the percarboxylic acid is between about 0.50 to 0.99.
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- Phyllanthostatin A
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An unusal cytostatic (PS ED50 4 ug/ml) lignan ester has been isolated from the Central American tree Phyllanthus acuminatus and is herein designated Phyllanthostatin A. Separation of a methanol extract of the root by size exclusion chromatography, high speed countercurrent distribution and semi-preparative hplc afforded glycoside in 0.007% yield. In solution, phyllanthostatin A was slowly transformed into justicidin-B. The structure of the lignan glycoside, determined by hrfabms and 2D nmr spectroscopy, is: STR1
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- Process for preparing alpha-substituted acetaldehydes
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Processes are described for the preparation of 2,2,6-trimethyl-1-cyclohexen-1-ylacetaldehyde (hereinafter referred to as "beta-cyclohomocitral" which either (A) comprises the steps of: I. Oxidizing beta-ionone having the formula: SPC1 with a peralkanoic acid having the formula: EQU1 (wherein R is H, methyl or ethyl) in the presence of buffer and in the absence of dimethyl formamide, to form 2,2,6-trimethyl-1-cyclohexen-1-ylvinylacetate (hereinafter referred to as beta-ionone enol ester) having the formula: SPC2 Ii. hydrolyzing said beta-ionone enol ester using a basic hydrolysis agent to form beta-cyclohomocitral having the structure: SPC3 Or (B) oxidizing beta-ionone with hydrogen peroxide in the presence of inorganic base to form beta-cyclohomocitral, directly.
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