Showing papers on "Isopropyl alcohol published in 1996"

Dehydrogenation of isopropylic alcohol on a Cu/SiO2 catalyst: a study of the activity evolution and reactivation of the catalyst

Abstract: The activation-deactivation behaviour of a Cu/SiO2 catalyst during isopropyl alcohol (IPA) dehydrogenation to acetone has been studied. Simultaneous reduction and sintering processes are responsible for the activation-deactivation behaviour observed. The reducing H2 atmosphere impulses the transformation of CuO into Cu0 and at the same time the sintering of the Cu0 phase formed. The reoxidation treatment in air at 573–673 K is able to regenerate a finely dispersed CuO phase from the sintered Cu0 phase. As a result, the active phase is redispersed and the dehydrogenation activity is recovered. The results indicate the existence of two CuO phases on the catalyst, with different properties. The CuO phase with a low reduction temperature, a small particle size and a poor crystallinity, is the one responsible for the appearance of the finely dispersed Cu0, which is the active phase for this reaction.

Kinetics of the Titanium Isopropoxide Decomposition in Supercritical Isopropyl Alcohol

Abstract: The formation of TiO2 powder from Ti(O-iC3H7)4 dissolved in supercritical isopropyl alcohol has been studied. Kinetic data were obtained in a temperature range of 531−568 K. A reaction mechanism has been proposed, based on a hydrolytic decomposition of Ti(O-iC3H7)4 by water produced in a catalytic dehydration of the isopropyl alcohol used as solvent and where the limiting steps are the decomposition reactions of the formed titanium hydroxides. In accordance with experimental results, such a mechanism leads to a first order kinetics relative to the precursor concentration. The activation energy was determined equal to 113 ± 16 kJ·mol-1, and an increase in the supercritical fluid density was found to decrease the overall reaction rate. The obtained results will be used to optimize the working of a continuous reactor producing submicronic TiO2 powder at a laboratory pilot scale.

Raman Spectroscopic Measurement of Oxidation in Supercritical Water. 2. Conversion of Isopropyl Alcohol to Acetone

Abstract: The oxidation of isopropyl alcohol in supercritical water has been investigated using Raman spectroscopy. Results for species concentration as a function of residence-time are presented for temperatures ranging from 400 to 480 °C at constant pressure, 24.4 ± 0.3 MPa, and constant equivalence ratio, 0.88 ± 0.02. Acetone has been identified as the principal intermediate formed and subsequently destroyed, during the oxidation process. By assuming first-order kinetics for the destruction of both isopropyl alcohol and acetone, effective first-order rate constants have been determined from fits of the experimental data. Assuming Arrhenius behavior, the fits yield rate constants for isopropyl alcohol, keff,ipa = 3.255 × 1022(s-1) exp[−301.1(kJ·mol-1)/RT], and for acetone, keff,ace = 1.948 × 1010(s-1) exp[−137.7(kJ·mol-1)/RT]. These results indicate that for temperatures greater than 425 °C, the destruction of isopropyl alcohol proceeds faster than that of acetone.

Method of extracting nucleic acids and method of detecting specified nucleic acid sequences

Abstract: An improved method of extracting nucleic acids from a sample comprising mixing the sample with a carrier which is at least one member selected from the group consisting of dextran, acrylamide and carboxymethyl cellulose to form a liquid mixture; mixing said liquid mixture with reagent C to render the nucleic acids and the carrier insoluble, said reagent C containing at least one reagent A selected from the group consisting of guanidinium thiocyanate, guanidinium hydrochloride, potassium thiocyanate and sodium thiocyanate and at least one reagent B selected from the group consisting of n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol, and tert-amyl alcohol; and separating the insolubilized nucleic acids and carrier from the liquid phase. The method is easier to use than the heretofore practiced procedures, involves a smaller number of steps, can reduce the possibility of aerosol generation, can be implemented within a short time, does not use phenol or chloroform, and yet it achieves a consistent efficiency in the extraction of nucleic acids. Also disclosed is a method of detecting a specified nucleic acid sequence.

Composition for external use

Abstract: PROBLEM TO BE SOLVED: To obtain a composition that has excellent endermic absorption and analgesic action by adding an alcohol and a carboxylate ester and/or a carboxylic acid. SOLUTION: This composition contains (A) 0.2-20wt.% of diclofenac or its salt, (B) 0.5-90wt.% of alcohol and (C) 0.5-20wt.% of a carboxylate ester and/or carboxylic acid. The component A is diclofenac sodium or diclofenac ammonium. The component B is a monohydric lower alcohol, for example, ethyl alcohol and/or isopropyl alcohol. The carboxylate ester is an ester from an aliphatic monocarboxylic acid and a monohydric alcohol and the carboxylic acid is an aliphatic carboxylic acid.

Dehydration and purification of isopropyl alcohol to an ultradry and ultrapure level

Abstract: A method for the on-site reprocessing of isopropyl alcohol used in semiconductor manufacturing, to generate an ultradry and ultrapure isopropyl alcohol. This ultradry and ultrapure isopropyl alcohol is produced through a pervaporation step, followed by double distillation. In the first distillation step, an autonomous azeotropic self-stripping distillation column is used to produce an ultradry and partially purified isopropyl alcohol. In the next step, the isopropyl alcohol is distilled in an overhead product distillation column, to produce an ultrapure and ultradry isopropyl alcohol. Alternatively, if the feed isopropyl alcohol contains less than 2000 ppm water, the pervaporation step may be omitted. The resulting isopropyl alcohol has between a high of 100 parts per million (ppm) and a low of 0.1 ppm of water in the isopropyl alcohol. It also has zero particles per milliliter of a size larger than 2.0 microns, zero to 2 particles per milliliter of a size of 0.5 micron to 2.0 microns, zero to 30 particles per milliliter of a size between 0.1 microns and 0.5 microns, an unspecified number of particles per milliliter below 0.1 microns, 1 part per trillion (ppt) to 1 part per billion (ppb) of any specific trace impurity such as metals, anions, and cations, and 10 ppt to 10 ppm of any other specific trace organic substances.

Surface chemistry of V–Sb–oxide in relation to the mechanism of acrylonitrile synthesis from propane. Part 1.—Chemisorption and transformation of possible intermediates

Abstract: The mechanism of propane ammoxidation to acrylonitrile on V–Sb–oxide is analysed by IR spectroscopy in three papers dealing with the study of (i) the reaction network in propane conversion, (ii) the relationship between ammonia chemisorbed species and catalytic behaviour and (iii) the effect of ammonia chemisorption on the surface reactivity. This first part deals with the study of the nature of surface adspecies formed by chemisorption of acetone, isopropyl alcohol, acrylic acid, ally alcohol, propene, propionic acid, acetic acid, propane and acrylonitrile on a vanadium antimonate catalyst (V/Sb = 1.0) and subsequent thermal treatment. The results indicate that the catalyst is characterized by multifunctional properties (H-abstraction, O-insertion and oxidative cleavage properties), the relevance of which for the mechanism and catalytic behaviour in acrylonitrile synthesis from propane is discussed. A surface reaction network in propane oxidation is also proposed involving multiple possible pathways of transformation. The main route of propane conversion is through the formation of propene as an intermediate, although a side reaction of acrylate formation via a propionate intermediate is possible. Propene may be oxidized according to two routes, the first leading to acetone which undergoes quick oxidative cleavage to an acetate species and a C1 fragment, and the second to the formation of an allyl alcoholate adspecies which transforms to acrolein which quickly further converts to an acrylate species. The acrylate species strongly interacts with the surface and is thermally stable up to relatively high temperatures.

Mixed alumina chromia pillared layered α-zirconium phosphate materials: acidity and catalytic behaviour for isopropyl alcohol decomposition

Abstract: The surface acidity and the catalytic behaviour of a series of mixed alumina chromia pillared cY-zirconium phosphates have been studied. The acid properties of these catalysts have been evaluated by measurements of the NH, thermal programmed desorption, pyridine adsorption and dehydration of isopropyl alcohol at 220°C. Both surface acidity and catalytic activity show a marked dependence on the AI/Cr ratio, but they are not a monotonic function of the catalyst composition. The most acid materials were those with Al/Cr ratios between 20,030 and 40/60. From this ratio, the acidity is gradually reduced with increasing Al concentration. The activity of the mixed alumina chromia pillared materials for isopropyl alcohol decomposition is considerably enhanced with respect to the analogous chromia pillared compounds of the order of 20 times for maximum activity. The most active materials were those with the highest micropore volumes. All catalysts show selectivities higher than 99% for the dehydration of isopropyl alcohol.

Topical deodorant compositions

Abstract: Topical deodorant and compositions are provided. The deodorant compositions include in the range of about 20 to about 80 percent by weight of an acetylsalicylic acid solution and in the range of about 20 to about 80 percent by weight of a waxy carrier. The acetylsalicylic acid solution has acetylsalicylic acid in the range of between about 5 percent by weight per unit volume of a solvent mixture up to saturation of the solvent mixture. This solvent mixture consists essentially of propylene glycol in the range of about 5 to 15 percent by volume, glycerin in the range of about 1 to 10 percent by volume, and the balance of the solvent mixture made up with one or more solvents selected from the group consisting of isopropyl alcohol, water, and ethanol, the balance of the solvent mixture comprising at least 50 percent by volume isopropyl alcohol. The waxy carrier preferably includes cetyl alcohol and sodium stearate. Thus, the composition has a waxy consistency for each of application to the skin for antiperspirant purposes.

Applying composition for preventing surface reflection and formation of pattern

Abstract: PROBLEM TO BE SOLVED: To satisfactorily form or remove an applied film having a low refractive index with an aqueous medium by using a fluorocompound in a specific molecular weight range via an aqueous solvent. SOLUTION: Perfluoroalkyl polyether carboxylic acid having the weight average molecular weight of 1100-6000 is used as a water-soluble fluorocompound. The perfluoroalkyl polyether carboxylic acid is the fluorocompound having the specific perfluoroalkyl polyether group in the molecular skeleton and one or two or more carboxylic acid groups in the molecule. Only water or various mixed solvents using water as the main component can be practically used as an aqueous solvent. In case of the mixed solvent, the mixed solvent with an organic solvent misible with water such as lower alcohol or lower alkyl carboxylic acid having five carbon atoms or less, which may be substituted by fluorine atom, is preferably used to improve the solubility of the fluorocompound. Isopropyl alcohol is preferably used as the solvent misible with water in particular. COPYRIGHT: (C)1997,JPO

Flavor and fragrance modifier for perfume and modifying method

Abstract: PROBLEM TO BE SOLVED: To provide a modifier for use in adding to a perfume which affords an improvement in flavor and fragrance characteristics to the perfume, by a method comprising subjecting a leaf of piper betle Line to the extraction with water, a water- containing lower alcohol or an alcohol not containing water. SOLUTION: This modifier for flavor and fragrance can be obtained by providing a raw leaf or a dried leaf of piper betle Line, optionally crushing the leaf, and subjecting the leaf to the extraction with an alcohol not containing water. As to an extracting solvent for a leaf of piper betle Line, the followings are mentioned. Water, a water-containing lower alcohol other than isopropyl alcohol, a lower alcohol not containing water and acetone have no significant difference from one another in effect in modifying the flavor and fragrance of a mint-type perfume. Hexane has only a low effect in such modification. Isopropyl, alcohol is disadvantageous sine it may adversely affect the fragrance of the extract because of its own singular smell. Methanol and acetone are both disadvantageous since they are difficult to be completely separated and removed from the extract. Taking in consideration of subsequent steps such as concentration and decolorization, the use of an alcohol having a water content of 65% or less is preferred. As pieced together from the above-mentioned results, an alcohol having a water content of 5 to 90% is most preferred.

Acetone in urine as biological index of occupational exposure to isopropyl alcohol.

Abstract: In order to investigate a role of acetone in urine (AcU, mg/l) as an indicator of occupational exposure to isopropyl alcohol (IPA, ppm), AcU was measured in 80 male workers exposed to this substance in a plastic factory. The exposure concentration of solvent was also monitored personal diffusive sampling in the individuals during morning 4-hr shift. Urine samples were collected near the end of the shift and were analyzed for acetone by head-space gas chromatography. The correlation between airbornre concentration of IPA and its urinary metabolite acetone was significant: AcU (mg/l) = 0.031 x IPA (ppm) + 0.608, r = 0.75, n = 80, P < 0.001. We established 44 ppm as the lowest airborne concentration of IPA that caused excessive urinary excretion of acetone which could be discriminated from the endogenous production of acetone in non-exposed people. This concentration was as low as one ninth to one tenth of the current exposure limit of 400 ppm. At higher concentrations than 44 ppm, AcU was found to be a useful index for monitoring occupational exposure to IPA.

Manufacture of laminate

Abstract: PURPOSE: To provide a laminate having gas barrier properties, fragrance keeping properties and resistance to oils and resistance to chemicals under low humidity and useful for various kinds of packaging by applying polyalcohol solution prepared by reducing a carbon monoxide-ethylene copolymer to a base and drying thereon CONSTITUTION: Polyalcohol solution prepared by reducing a carbon monoxide- ethylene copolymer is applied onto a base and drying thereon to manufacture a laminate It is preferable that the repeating unit particularly represented by the formula is 80% or more, more preferably 95% or over is contained in polyalcohol, and further it is optimum that 97% or over is contained therein As apolyalcohol solvent, methyl alcohol, normal propyl alcohol, isopropyl alcohol or the like is preferable, and electrolyte of 001-05wt% (to polymer) can be blended therein for the purpose of lowering viscosity It is also preferable to apply preliminarily a bonding agent on the surface of the base and dried thereon by the dry lamination method, which is what is called the anchor coating

Production of high-purity epoxy resin

Abstract: PURPOSE:To obtain a high-purity epoxy resin contg. minute amts. of org. chlorine compds. by reacting a phenolic hydroxyl compd. with an epihalohydrin in the presence of an alkali metal hydroxide and a specific mixed solvent. CONSTITUTION:A phenolic hydroxyl compd. (e g. a naphthol novolak resin) and an epihalohydrin (e.g. epichlorohydrin) are dissolved in a mixed solvent comprising a tert. monohydric alcohol (e.g. tert. butyl alcohol) and a sec. monohydric alcohol (e.g. isopropyl alcohol). An alkali metal hydroxide (e.g. sodium hydroxide) is added as the catalyst to the soln., which is then heated to 30-80 deg.C to react the phenolic hydroxyl compd. with the epihalohydrin, giving a high-purity epoxy resin. Thus, the contents of hydrolyzable chlorine and total chlorine can be reduced and an epoxy resin suitable as a sealant for a highly integrated circuit can be obtd.

Influence of organic modifier and temperature on the enantiomeric separation of γ-lactams by HPLC

Abstract: A high-performance liquid chromatographic method is reported for the resolution of the enantiomers of a series of fused γ-lactams (2,7-diaza-3-oxo[3.3.0]octan-6-ones) with probable anti-HIV and anticancer activity. Resolution was achieved on a Chiralcel® OD column, cellulose tris-(3,5-dimethylphenyl carbamate) adsorbed on macroporous silica gel; mixtures ofn-hexane and isopropyl alcohol in different proportions were used as the mobile phase. The analysis was studied at different temperatures.

Two-stage process for producing diisopropyl ether using catalytic distillation

Abstract: A process for the efficient production of diisopropyl ether where catalytic distillation is used to increase the yield of product beyond thermodynamic equilibrium limitations has been developed. In a hydration zone the propylene in a feedstock is reacted with water in the presence of a catalyst to effect hydration to produce an effluent stream containing at least water, unreacted propylene, and isopropyl alcohol, and then, in an etherification zone, at least a portion of the effluent stream is further reacted by catalytic distillation in the presence of a catalyst to effect reaction of propylene and isopropyl alcohol to form diisopropyl ether while concurrently separating an organic portion containing the diisopropyl ether and an aqueous portion, and collecting the organic portion containing the diisopropyl ether.

Synthesis of Ethyl Salicylate Using Household Chemicals

Abstract: Ethyl salicylate is synthesized, isolated, and characterized in a three-step process using simple equipment and household chemicals. First, acetylsalicylic acid is extracted from aspirin tablets with isopropyl alcohol, then hydrolyzed to salicylic acid with muriatic acid, and finally, the salicylic acid is esterified using ethanol and a boric acid catalyst. The experiment can be directed towards high school or university level students who have sufficient background in organic chemistry to recognize the structures and reactions that are involved.

Process for producing isopropyl alcohol

Abstract: A process for producing isopropyl alcohol by hydrating directly propylene and water in the presence of a strong acid solid catalyst which includes feeding continuously propylene, water which is the same as or more than propylene in terms of mole, and a saturated hydrocarbon (propane, butane and the like) to a reactor in which the above solid catalyst is filled or suspended, and carrying out a hydration reaction in the conditions of 50° to 200° C. and 60 to 250 atm while maintaining the concentration of isopropyl alcohol contained in the reaction liquid at 6 to 30 weight %, and then drawing a vapor phase out of the reactor, liquefying a part of thereof by reducing the pressure or cooling to separate vapor components, and refining crude isopropyl alcohol contained in the liquid phase to obtain refined isopropyl alcohol.

Water-soluble peeling fluid for cleaning and production thereof

Abstract: PURPOSE: To obtain a water-soluble cleaning composition which has high cleaning and peeling effects, causes no destruction of global and natural environments, is safe for the human body, free from ozonosphere depletion, underground water pollution, a fire, a carcinogen, a respiratory trouble, a skin trouble, etc., and easy to handle and can be used without anxiety. CONSTITUTION: A water-soluble peeling fluid composition for cleaning which consists of a carboxylated sodium chondroitin sulfate, monosaccharides comprising cyclodextrin, sodium pyruvate, polysaccharides comprising xanthan gum, xylan, xylose, glucose, natural, microbial and basidiomycetous glucoses, a fortifier comprising sodium pantothenate, a fermentation lactic acid comprising sodium pyruvate, an antioxidant comprising sodium erysorbate, an antiseptic, antibacterial preservative comprising 4-isopropyltropone, pure water, benzyl alcohol and isopropyl alcohol.

Use of Water-Based Solvent Preparations in Factories in Japan

Abstract: Use of Water-Based Solvent Preparations in Factories in Japan: Hirohiko UKAI, et al. Kyoto Industrial Health Association-Prevalence of water-based solvent preparations in 122 factories of various types (e.g., painting, printing, etc.) in the city of Kyoto was investigated by interview in 1995. The survey showed that water-based solvent preparations were used in 20% of the factories studied and that the leading organic solvent components in water-based solvent preparations were methyl, ethyl and isopropyl alcohols, among which the use of isopropyl alcohol was the most common. Among glycol derivatives, 2-butoxyethanol was the most frequently used. (J Occup Health 1996; 38: 124-127)

The influence of α- and β-Si3N4 precursors on formation of α-SiAlON ceramics

Abstract: During the formation of α-SiAlON from a powder mixture wet-milled in isopropyl alcohol at a temperature of 1500–1600 °C there appears considerable amount of β-SiAlON. β-SiAlON is formed in high α- as well as in high β-Si 3 N 4 starting powders. The β-SiAlON is dissolved at higher temperatures. The rate of dissolution of α-Si 3 N 4 was observed to be higher than that of β-Si 3 N 4 and the densification and rate of α-SiAlON formation is higher in high α-Si 3 N 4 powder.

Composition for sterilization and disinfection

Abstract: PROBLEM TO BE SOLVED: To obtain a composition for sterilization and disinfection which shows strong bactericidal activity and its sustainability without causing dryness of skin and lack of pliableness by adding specific five compounds into an alcohol for disinfection. SOLUTION: This composition is prepared by adding (a) benzalconium chloride, (b) propylene glycol, (c) glycerol and (d) triethanolamine into an alcoholic medium. Benzalconium chloride, propylene glycol, glycerol and ethanolamine in the alcoholic medium are preferably formulated in amounts of about 0.1-1.0wt.%, about 1.0-2.0wt.%, about 0.1-1.0wt.% and about 0.1-0.5wt.%, respectively. As the alcoholic medium, ethyl alcohol and isopropyl alcohol are preferable and used as the solutions of 70-90w/v%. The composition can disinfect readhered bacteria and is possible to be successively used for a long term due to the protective activity for skin and extremely effective for protection from spread of hospital infection caused by MRSA(methicillin-resistant Staphylococcus aureus).

The Effect of Acidity of Al and Fe Silicates with MFI Structure on Benzene and Toluene Alkylation with Isopropyl Alcohol

Abstract: Kinetic study of toluene and benzene alkylation with isopropyl alcohol on alumo- and ferrisilicates of MFI structure has shown that the alkylation activity does not follow the acidity (both the number and strength of bridging OH groups) of these molecular sieves. The rate of the overall reaction is controlled by the desorption/transport rate of bulky, strongly adsorbed cymenes and cumene. A higher concentration of n-propyltoluenes compared to n-propylbenzene, both undesired reaction products, formed via a bimolecular isomerization of isopropyl aromate with benzene or toluene, was due to the higher reactivity of isopropyltoluene with toluene in comparison with that of cumene with benzene. It is concluded that ferrisilicates of MFI structure possessing low strength acid sites appear to be promising catalysts for achieving both a high isopropyl- and para-selectivity in toluene alkylation to p-cymene.

Low vapor pressure solvent

Abstract: An advantageous effective cleaning solvent consisting essentially, according to one embodiment, of methyl ethyl ketone, methyl isobutyl ketone, isopropyl alcohol, toluene and n-butyl acetate, in certain ranges of proportions. Water also is included to aid in reducing the vapor pressure of the solvent. The composite vapor pressure of the solvent, at 20° C., neglecting the vapor pressure contribution of water, is not greater than 35 mm of mercury. The invention solvent is particularly effective as a paint cleaner, e.g. for cleaning paint guns.

Production of hesperetin momoglucoside

Abstract: PROBLEM TO BE SOLVED: To obtain the subject compound useful for a food additive, an antioxidant, etc., by dissolving hesperidin with an aqueous alkali solution for forming a chalcone, adding an organic solvent and an acid for hydrolyzing the hesperidin to impart a water solubility thereto and expand usages thereof. SOLUTION: This method for producing hesperetin monoglucoside useful for a food additive, an antioxidant, etc., is to dissolve hesperidin as a flavonoid extracted from lees of a mandarin orange, into an aqueous alkali solution for forming a chalcone, add a water soluble organic solvent such as isopropyl alcohol, n-propyl alcohol, ethyl alcohol and methyl alcohol, for preparing a solution of the chalcone-hesperidin, then add an acid such as 1.0-1.5N hydrochloric acid to the solution for hydrolyzing hesperidin with the acid to impart a water solubility thereto and expand usages thereof. COPYRIGHT: (C)1997,JPO