Showing papers on "Methyl isobutyl ketone published in 1999"
TL;DR: In this article, the one-step synthesis of methyl isobutyl ketone (MIBK) from acetone and hydrogen over Cu-on-MgO catalysts was studied at atmospheric pressure in a fixed bed continuous flow reactor.
77 citations
TL;DR: In this paper, NiMgAl selectively gives methyl isobutyl ketone (MIBK), CoMgal gives methyl carbinol (MIBC) and FeMg aloxide (MSO) which are all valuable chemicals.
Abstract: Layered double hydroxides or hydrotalcite-like materials containing Ni, Co and Fe are prepared by coprecipitation technique. They are characterized by XRD, hydrogen and oxygen adsorption measurements, determination of acidity and surface area. Acetone conversion in presence of hydrogen has been carried out over these compounds at 373 K and at a pressure of 1 atm. They are found to be efficient catalysts in the selective conversion of acetone. NiMgAl selectively gives methyl isobutyl ketone (MIBK) whereas CoMgAl gives methyl isobutyl carbinol (MIBC) and FeMgAl produces mesityl oxide (MSO) which are all valuable chemicals. The formation of different products is related to the bifunctional nature of the catalysts involving both metallic and acid–base nature. The activity and product selectivity obtained are compared with those obtained over coprecipitated alumina-supported Ni, Co and Fe catalysts containing the same metal content. A mechanism of product formation is proposed.
65 citations
TL;DR: In this paper, a fixed-bed dynamic reactor at 160°C, 1 atm pressure and acetone/H2 molar ratio=3 was used for methyl isobutyl ketone (MIBK) synthesis.
Abstract: Acetone transformation into methyl isobutyl ketone (MIBK) was studied using a fixed-bed dynamic reactor at 160°C, 1 atm pressure and acetone/H2 molar ratio=3 The reaction was carried out over Pt/HMFI bifunctional catalysts, with 030 wt% of platinum which was supported over three aluminosilicates (Si/Al ratio=40, 95 and 160) and a borosilicate (Si/B ratio=44) with similar dispersion The results show that catalytic properties depend greatly on density and strength of the acidic sites of the catalysts Moreover, the limiting step of the MIBK synthesis reaction (aldolization of two acetone molecules) is carried out over the acidic sites of the aluminosilicates, but not over those of the borosilicate, which considerably affects reaction selectivity
30 citations
TL;DR: Excess molar enthalpies (H E ) at 298.15 K of N,N-dimethylformamide with a series of ketones were measured by using a Parr 1451 solution calorimeter as discussed by the authors.
30 citations
TL;DR: The model predicts that high equilibrium yields of butyric acid can be achieved only in the absence of ammoniolysis or in the presence of a separate water phase, however, high yields ofbutyramide should be possible if the water concentration is fixed at a low level and a more suited source of ammonia is applied.
Abstract: Enzymatic ester hydrolysis and ammoniolysis were performed as competitive reactions in methyl isobutyl ketone without a separate aqueous phase. The reaction system contained solid ammonium bicarbonate, which dissolved as water, ammonia, and carbon dioxide. During the reaction an organic liquid phase, a vapor phase, and at least one solid phase are present. The overall equilibrium composition of this multiphase system is a complex function of the reaction equilibria and several phase equilibria. To gain a quantitative understanding of this system a mathematical model was developed and evaluated. The model is based on the mass balances for a closed batch system and straightforward relations for the reaction equilibria and the solubility equilibria of ammonium bicarbonate, the fatty acid ammonium salt, water, ammonia, and carbon dioxide. For butyl butyrate as a model ester and Candida antarctica lipase B as the biocatalyst this equilibrium model describes the experiments satisfactorily. The model predicts that high equilibrium yields of butyric acid can be achieved only in the absence of ammoniolysis or in the presence of a separate water phase. However, high yields of butyramide should be possible if the water concentration is fixed at a low level and a more suited source of ammonia is applied.
29 citations
31 Jul 1999-Materials Science and Engineering A-structural Materials Properties Microstructure and Processing
TL;DR: In this paper, a self-sustaining reaction between Cu2O and Mg in stoichiometric amounts and additional ball milling was characterized by physical methods (DSC, XRD, and XPS).
Abstract: Cu40Mg60 amorphous alloy powders, prepared by mechanical alloying of the constituent elements, and Cu–MgO samples, made by the self-sustaining reaction between Cu2O and Mg in stoichiometric amounts and additional ball milling, were characterized by physical methods (DSC, XRD, and XPS). The catalytic properties of the specimens were tested in the dehydrogenation of 2-propanol and in the one-step synthesis of methyl isobutyl ketone from acetone. The samples exhibited high activities and selectivities in the dehydrogenation of 2-propanol. In contrast, their overall performance in the synthesis of methyl isobutyl ketone is inferior to that of Cu-on-MgO prepared by conventional methods. The catalytic performances of the samples are interpreted by the structural and surface changes induced by the catalytic reactions.
16 citations
TL;DR: Dynamic and flow-through flux chambers are convenient tools for field measurements of gas or VOC emission flux from solid surfaces in the field and analyses show that hexanal was the common and principal compound for all three types of tracks.
13 citations
31 Jul 1999-Materials Science and Engineering A-structural Materials Properties Microstructure and Processing
TL;DR: In this paper, the results concerning the acetone conversion to methyl isobutyl ketone promoted by mechanical energy were presented, and the results were followed under Ar and H 2 reaction atmosphere and as a function of the impact energy.
Abstract: Selected results concerning the acetone conversion to methyl isobutyl ketone promoted by mechanical energy are presented. Cu–MgO composites at different Cu contents and amorphous Cu 40 Mg 60 , prepared by different ball milling techniques, were employed as solid substrates for the mechanochemical process. The conversion and selectivity values of the acetone transformation were followed under Ar and H 2 reaction atmosphere and as a function of the impact energy. The mechanical treatment under H 2 resulted mainly in acetone hydrogenation leading to 2-propanol, while under Ar, the formation of diacetone alcohol, mesityl oxide and methyl isobutyl ketone (MIBK) was observed. Conversion changes and selectivity shifts were observed depending on the substrates employed, and the largest amount of MIBK was obtained when amorphous Cu 40 Mg 60 was used. An important structural transformation occurred during the mechanochemical runs.
12 citations
TL;DR: Three commercially available conversion varnish coating "systems" (stain, sealer, and topcoat) were selected for an initial scoping study and the primary volatile organic constituents included methyl ethyl ketone (MEK), isobutanol, n-butanol, methyl isOButyl ket one (MIBK), toluene, ethylbenzene, the xylenes, and 1,2,4-trimethylbenzenes.
Abstract: Three commercially available conversion varnish coating “systems” (stain, sealer, and topcoat) were selected for an initial scoping study The total volatile content of the catalyzed varnishes, as determined by US Environmental Protection Agency (EPA) Method 24, ranged from 64 to 73 weight% Uncombined (free) formaldehyde concentrations, determined by a sodium sulfite titration method, ranged from 015 to 058 weight% of the uncatalyzed varnishes Each sealer and topcoat was also analyzed by gas chromatography (EPA Method 311) The primary volatile organic constituents included methyl ethyl ketone (MEK), isobutanol, n-butanol, methyl isobutyl ketone (MIBK), toluene, ethylbenzene, the xylenes, and 1,2,4-trimethylbenzene
11 citations
Patent•
20 Oct 1999
TL;DR: In this article, a photomask plate with a film surface protection layer is characterized, in which a protective layer forming solution is prepared by mixing a main constituent comprising a two-liquid cross-linked antifouling surface coating agent, prepared by combining a mixed resin of a fluororesin and an acrylic resin in a solvent mixture of n-butyl acetate, methyl ethyl ketone (MEK), and methyl isobutyl kone (MIBK), with a cross-linking curing agent.
Abstract: A photomask plate with a film surface protective layer is characterized in that a protective layer forming solution is prepared by mixing a main constituent comprising a two-liquid cross-linked antifouling surface coating agent, prepared by combining a mixed resin of a fluororesin and an acrylic resin in a solvent mixture of n-butyl acetate, methyl ethyl ketone (MEK) and methyl isobutyl ketone (MIBK), with a cross-linking curing agent, prepared by mixing a polyisocyanate prepolymer and ethyl acetate, and a diluent comprising n-butyl acetate, methyl ethyl ketone (MEK) and cellosolve (ethylene glycol monoethyl ether) acetate. This protective layer forming solution is applied to a film surface of a photomask plate photosensitive emulsion layer produced by forming the film surface of the photosensitive emulsion layer (an emulsion photomask) on a substrate. The protective layer forming solution is then aged to form a film surface protective layer in a laminated manner. The resulting inexpensive and durable photomask is protected from being soiled or marked while having minimal reduction in ultraviolet light transmittance.
7 citations
TL;DR: The racemic myxobacterial pheromone (±)-1 (stigmolone), which induces the formation of the fruiting body of Stigmatellaaurantiaca, was synthesized from methyl isobutyl ketone in 48% overall yield in four steps.
Patent•
30 Apr 1999
TL;DR: In this article, the authors proposed to positively change capacitance of a capacitor against a frequency, by setting content of powder constituting coating, and showing a specified powder frequency characteristic index to be specified weight % against resin.
Abstract: PROBLEM TO BE SOLVED: To positively change capacitance of a capacitor against a frequency, by setting content of powder constituting coating, and showing a specified powder frequency characteristic index to be specified weight % against resin SOLUTION: Porous silica, barium titanate, titanium oxide, barium stannate, calcium carbonate in a range where powder frequency characteristic index is not less than 15% are used as powder contained in the coating layer of a plastic film When powder is distributed in a resin layer and it is applied on the plastic film, the content of powder is set to be 20-80 weight % against whole application quantity The surface ratio resistance of the coating layer is set to be not more than 10 Ω/(square) The content of organic solvent is to be to 01-30 ppm and ethyl acetate, methyl ethylketone, methyl isobutyl ketone, toluene, xylene and cyclohexanone exist for organic solvent
TL;DR: In this article, the Ni-added CaCO 3 did not decompose directly into CaO and CO 2 but via the route of CaCO3 + 4H 2 → CaO + CH 4 + 2H 2 O, supposed to have a relatively low activation barrier.
Abstract: One step synthesis of MIBK (methyl isobutyl ketone) from acetone over co-impregnated Ni-CaO catalyst and Ni effect on the thermal decomposition of CaCO 3 into CaO were studied. Bulk calcium acetate, one of catalyst precursors, decomposed into CaCO 3 and acetone at 400-450 °C, and CaCO 3 into CaO and CO 2 at 700 °C But, when nickel acetate for 2 wt% Ni was added into calcium acetate, the decomposition temperature of CaCO 3 was decreased to 500 °C in H 2 /N 2 stream but not in O 2 /N 2 stream or air, and in case of 20 wt% Ni, this phenomenon was more drastic. From TPD-MS experiment, we found out that Ni-added CaCO 3 did not decompose directly into CaO and CO 2 but via the route of CaCO 3 + 4H 2 → CaO + CH 4 + 2H 2 O, supposed to have a relatively low activation barrier. CaO can be formed even at 500 °C with the aid of Ni and H 2 . When 2 wt% Ni-CaO reduced at 500 °C for one step synthesis of MIBK was used, 60 – 80% of acetone overall conversion and 50 – 60% of MIBK selectivity were obtained.
Patent•
20 Apr 1999
TL;DR: In this paper, the α,ω-dicarboxylic acid is used as a cross-linking agent in a coating material composition by purifying the α and O(D)DICARBOXYCLIC acid produced by a fermentation method of a normal paraffin as a raw material until the nitrogen content of minor impurities therein reaches a specific value.
Abstract: PROBLEM TO BE SOLVED: To obtain an α,ω-dicarboxylic acid useful as a cross-linking agent in a coating material composition by purifying the α,ω-dicarboxylic acid produced by a fermentation method of a normal paraffin as a raw material until the nitrogen content of minor impurities therein reaches a specific value. SOLUTION: A solvent having functions to dissolve at least a part of, e.g. an α,ω-dicarboxylic acid produced by a fermentation method of a normal paraffin as a raw material and having >=500 ppm nitrogen content, e.g. brassilic acid, tetradecanedioic acid, pentadecanedioic acid, hexadecanedioic acid and octadecanedioic acid (e.g. isopropyl acetate, n-propyl acetate or methyl isobutyl ketone) is mixed with the α,ω-dicarboxylic acid to deposit and remove impurities insoluble in the above solvent and impurities soluble in the solvent are adsorbed on active carbon and removed therefrom. The α,ω-dicarboxylic acid dissolved in the solvent is then recovered to thereby purify the α,ω-dicarboxylic acid until the nitrogen content reaches 0-100 ppm.
Patent•
01 Sep 1999
TL;DR: In this article, the cracking waste liquid is first regulated to alkaline, added with hydrogen peroxide solution and distilled to separate out methyl isobutyl ketone, then the residual part is cooled and deposited, and then the supernatant is regulated to the alkaline added with HPC solution, heated while adding active carbon, then cooled and filtered; and the filtrate is produced into phenylacetic acid product through acidification and crystallization.
Abstract: The cracking waste liquid is first regulated to alkaline, added with hydrogen peroxide solution and distilled to separate out methyl isobutyl ketone. The residual part is cooled and deposited, and then the supernatant is regulated to alkaline added with hydrogen peroxide solution, heated while adding active carbon, then cooled and filtered; and the filtrate is produced into phenylacetic acid product through acidification and crystallization, centrifugal dewatering and drying. The said technological process has high phenylacetic acid recovering rate, realizes the utilization of the waste liquid, and reduces environmental pollution.
TL;DR: In this paper, the boiling points of the binary systems 4-methyl-2-pentanone + octane and hexane + 1,3-dioxolane were determined.
Abstract: Vapor-liquid equilibrium at 94 kPa has been determined for the binary systems 4-methyl-2-penatanone (methyl isobutyl ketone) + octane and hexane + 1,3-dioxolane. the system 4-methyl-2-pentanone + octane behaves like a regular solution, with moderate deviations from ideal behavior, and presents an azeotrope that boils at 384.05 K and contains 70 mole % ketone. the system hexane + 1,3-dioxolane deviates strongly from ideal behavior and has an azeotrope that boils at 332.76 K and contains 55 mole % hexane. the activity coefficients and boiling points of both binary systems were well correlated with its composition by the Redlich-Kister, Wohl, Wilson. UNIQUAC, NRTL and Wisniak-Tamir equations.
Patent•
07 Sep 1999
TL;DR: In this article, the problem of obtaining an organic-compound-containing water-based composition, especially, an organic coating, an ink, or an agricultural composition, having a lowered equilibrium surface tension and a lowered dynamic surface tension by using an alkylated polyamine as the surfactant was addressed.
Abstract: PROBLEM TO BE SOLVED: To obtain an organic-compound-containing water-based composition, especially, an organic coating, an ink, or an agricultural composition, having a lowered equilibrium surface tension and a lowered dynamic surface tension by using an alkylated polyamine as the surfactant. SOLUTION: The surfactant used is an alkylated polyamine represented by the formula (wherein m is 2-6; n is 2 or 3; and R and R' are each a 5-8C alkyl). It is desirable that an aqueous solution of the alkylated polyamine has a dynamic surface tension of 45 dye/cm or below when measured in a concentration of 5 wt.% or below at 23 deg.C and has one bubble/sec when measured by the maximum bubble pressure method. The alkylated polyamine is obtained by reductively alkylating a polyamine with an aldehyde or a ketone. For example, it is desirably carried out by the reductive alkylation of diethylenetriamine with methyl isoamyl ketone or the reductive alkylation of di(3- aminopropyl)amine with methyl isobutyl ketone.
Patent•
14 Jan 1999
TL;DR: Tantalum and niobium are recovered from raw materials contg. both elements by: digestion (fusion) using exclusively HF; sepn. of Ta and Nb from each other as fluoro-complexes by solvent extn. as discussed by the authors.
Abstract: Tantalum and niobium are recovered from raw materials contg. both elements by: digestion (fusion) using exclusively HF; sepn. of Ta and Nb from accompanying elements; sepn. of Ta and Nb from each other as fluoro-complexes by solvent extn. of the fusion soln. using methyl isobutyl ketone (MIBK); washing the loaded MIBK with exclusively water. The resultant aq. wash soln. is removed separately from the extn. operation.
Patent•
26 Jan 1999
TL;DR: In this paper, the problem of obtaining hydroxypropylcellulose in a manner that the solvent can be easily recycled by reacting an alkali cellulose with propylene oxide in a reaction solvent being an aliphatic ketone having a specified number of carbon atoms is addressed.
Abstract: PROBLEM TO BE SOLVED: To obtain hydroxypropylcellulose in a manner that the solvent can be easily recycled by reacting an alkali cellulose with propylene oxide in a reaction solvent being an aliphatic ketone having a specified number of carbon atoms SOLUTION: The aliphatic ketone used is one having 6-10 carbon atoms and is desirably methyl isobutyl ketone, methyl n-amyl ketone or methyl n-hexyl ketone The cellulose as the starting material is a sheety or powdery wood pulp, cotton linter or the like The aqueous alkali solution is a 10-40 wt% solution of eg sodium hydroxide and is used in an amount 02-08 time as large as that of the cellulose The amount of the propylene oxide used is 10-60 times as large as that of the alkali cellulose The amount of the reaction solvent used is 06-20 times as large as that of the cellulose by weight The reaction temperature is 40-80 degC, and the reaction time is 3-10 hr
Patent•
24 Aug 1999
TL;DR: In this paper, the problem of obtaining a nonionic type, water-soluble, modified cellulose having free OH group, useful as a thickening agent for aqueous solutions, binders and coating by reacting water-ssoluble cellulose or the like with a multifunctional isocyanate under specific conditions is addressed.
Abstract: PROBLEM TO BE SOLVED: To obtain a nonionic type, water-soluble, modified cellulose having free OH group, useful as a thickening agent for aqueous solutions, binders and coating by reacting water-soluble cellulose or the like with a multifunctional isocyanate under specific conditions. SOLUTION: This cellulose is obtained by reacting (A) at least one of water- soluble cellulose, cellulose ether and cellulose ester having free OH group (preferably methyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose and carboxymethyl cellulose) with (B) 0.2 to 10 wt.%, based on the cellulose, preferably 0.2 to 5.0 wt.%, of a multifunctional isocyanate at 40 to 100 deg.C, preferably in the presence of an inert organic solvent (e.g. acetone, methyl isobutyl ketone or toluene). The reaction mixture preferably contains a catalyst which promotes the reactions between the isocyanate and hydroxyl group.
TL;DR: In this article, a solvent extraction-flame atomic absorption spectrometer was used for the determination of dissolved zinc in saline waters, using a well established solvent extraction and flame atomic absorption method (ammonium pyrollidine dithiocarbamate, methyl isobutyl ketone).
Abstract: A rapid, precise and sensitive solvent extraction-atomic spectrometric technique has been developed for the determination of dissolved zinc in saline waters, using a well established solvent extraction-flame atomic absorption spectrometry method (ammonium pyrollidine dithiocarbamate — methyl isobutyl ketone). The concentration range of the technique covers levels found in estuarine and coastal waters for analytical batches of 22 samples. The limit of detection of the technique is estimated as 0.7 μg L−1. Data for spiking recovery and long term standard deviation of determination are presented.
TL;DR: A mixture of methyl ethyl ketone (MEK) and toluene is widely used as solvents in industrial installations as mentioned in this paper, and the basic problems in the practical use of these solveents are considered in [1, 3].
Abstract: Dewaxing with selective solvents at low temperatures is unavoidable in production of lube oils from paraffinbase crude oils. A mixture of acetone or methyl ethyl ketone (MEK) and toluene is widely used as solvents in industrial installations. Ketones are used for precipitating solid paraffinic hydrocarbons, and toluene is used for dissolving the oil part of the feedstock. The basic problems in the practical use of these solvents are considered in [1–3].
Patent•
08 Jun 1999
TL;DR: In this article, an epoxy-based primer composition is proposed to provide an one-pack type epoxy based primer composition able to form a dry film especially excellent in low-temperature drying characteristics, solvent resistance and adhesiveness, and excellent in storage stability.
Abstract: PROBLEM TO BE SOLVED: To provide an one-pack type epoxy-based primer composition able to form a dry film especially excellent in low-temperature drying characteristics, solvent resistance and adhesiveness, and excellent in storage stability as well. SOLUTION: This composition is prepared by including (A) an epoxy resin having two or more epoxy groups in a molecule and (B) a ketimine compound obtained through reaction of a primary amine with (a) methyl ethyl ketone and (b) methyl isobutyl ketone and (C) a dehydrating agent. The ketimine compound contains ketimine groups derived from the ketone (a) and the ketone (b) in the ratio (a)/(b) of 0.05-4.0. The equivalent weight ratio between epoxy groups (c) in the epoxy resin and active hydrogen groups (d) in the ketimine compound is in the ratio (d)/(c) of 0.1-2.0.
Patent•
28 Sep 1999
TL;DR: In this paper, the problem of obtaining a compound containing a primary nitrogen atom and a polyoxyalkylene chain in one molecule by introducing a specific structure into the compound was solved, where the objective compound has a structure of formula I (R and R are each an alkylene; R is H or a hydrocarbon group; (m) and n) are each >= 1).
Abstract: PROBLEM TO BE SOLVED: To obtain the subject compound containing a primary nitrogen atom and a polyoxyalkylene chain in one molecule by introducing a specific structure into the compound. SOLUTION: The objective compound has a structure of formula I (R and R are each an alkylene; R is H or a hydrocarbon group; (m) and (n) are each >=1). The compound of formula I can be produced e.g. by reacting (A) a polyamine of the formula; H2 N-(R -NH)m -R -NH2 (e.g. diethylenetriamine) with (B) a ketone of formula II (R and R' are each a hydrocarbon group) (e.g. methyl isobutyl ketone) at an A:B molar ratio of 1:2 to 1:8 under normal pressure at 70-150 deg.C for 3-20 hr to form (C) an intermediate of formula III, adding (D) an oxide of formula IV to the intermediate C at 80-150 deg.C under a pressure of 1-1.5 kg/cm spending 3-20 hrs, adding water to the addition product and refluxing at 80-120 deg.C to eliminate the ketone-originating hydrocarbon group of formula V added to the terminal.
Patent•
27 Jul 1999
TL;DR: In this paper, an antifoaming agent composition for high temperature organic solvent comprising specified weight percents of a silicone oil containing a perfluoroarlyl group represented by a particular formula, methyl isobutyl ketone and methylene chloride.
Abstract: PROBLEM TO BE SOLVED: To reduce replacement frequency and consumption of a cleaning liquid and reduce amount of liquid replacement work so as to reduce cost by employing an antifoaming agent composition for high temperature organic solvent comprising specified weight percents of a silicone oil containing a perfluoroarlyl group represented by a particular formula, methyl isobutyl ketone and methylene chloride. SOLUTION: Twenty to sixty wt.% of methyl isobtyl ketone or a fluorohydrocarbon having a boiling point of 30 deg.C or higher is added to a silicone oil containing a prefluoroarkyl group represented by the formula (in the formula, Me represents a methyl group, n represents an integer of 4-8, and q and p represent 50-500, respectively). Further, 20-60 wt.% of a chlorine-containing solvent containing methylene chloride, chloroform, carbon tetrachloride or the like is added so as to prepare an anti-foaming agent composition for high temperature organic solven. Addition of the composition to a vapor cleaning liquid is carried out at the time when the vapor cleaning liquid starts foaming during execution of vapor cleaning or before a start of cleaning. By such a procedure, quality troubles are avoided, amount of liquid replacement work and liquid consumption can be reduced and a large cost reduction can be effected.
Patent•
15 Jun 1999
TL;DR: In this article, an organic solvent consisting of 40-90 wt.% of poor solvent was selected from the group consisting of benzene, tluene, xylene, propanol, hexanol, and 10-60 wt% of good solvent.
Abstract: PROBLEM TO BE SOLVED: To provide a vinyl chloride resin laminated sheet, which can be manufactured without requiring valuable facilities and in which no discoloring develops due to high temperature. SOLUTION: This vinyl chloride resin laminated sheet is obtained by applying a vinyl chloride resin organo-sol consisting of a vinyl chloride resin and an organic solvent on one side of a vinyl chloride resin sheet and then dried and fused under heat. The organic solvent consists of 40-90 wt.% of poor solvent, which is selected from the group consisting of benzene, tluene, xylene, propanol, hexanol, hexane and 10-60 wt.% of good solvent, which is selected from the group consisting of methyl isobutyl ketone, diisobutyl ketone, tetrahydrofuran, diacetone alcohol, isoamyl acetate and cyclohexanon.
Patent•
24 Aug 1999
TL;DR: In this paper, the aldol condensation of a ketone branched at the carbon atom in the β-position with an aldehyde branching at the α-position is carried out in the presence of an aqueous solution of an alkali metal hydroxide at 30-55%, preferably 40-50% concentration thereof at 60-130 deg.C, and the produced water is preferably continuously separated and removed from the reactional mixture.
Abstract: PROBLEM TO BE SOLVED: To produce the subject compound by an improved method (in an excellent-addition ratio and selectivity) by carrying out the aldol condensation of a ketone branched at the carbon atom in the β-position with an aldehyde branched at the carbon atom in the α-position and subsequent hydrogenating reaction. SOLUTION: The aldol condensation of (A) a 6-8C alkyl methyl ketone branched at the carbon atom in the β-position (e.g. methyl isobutyl ketone) with (B) a 4-15C aldehyde branched at the carbon atom in the α-position (e.g. 2-ethylhexanal) is carried out in the presence of an aqueous solution of an alkali metal hydroxide at 30-55%, preferably 40-50% concentration thereof at 60-130 deg.C, preferably 80-120 deg.C to produce (B) an α,β-unsaturated ketone, which is subsequently hydrogenated to afford a saturated alcohol. At the time of the aldol condesation, the produced water is preferably continuously separated and removed from the reactional mixture.
TL;DR: In this article, the graphite surface was examined following the evaporation of each solvent at temperatures ranging from 25°C to 300°C, and a linear relationship was found between the height and diameter of the isolated features.
Patent•
23 Nov 1999
TL;DR: In this article, the arylsulfonylureide compound which is of value as a color developer is provided in high yield and high purity by a simple procedure, which is described in detail.
Abstract: The arylsulfonylureide compound which is of value as a color developer is provided in high yield and high purity by a simple procedure. The technology of the invention for producing an arylsulfonylureide compound of general formula (1) (Ar1 --SO2 NHCONH)n --Ar2 (1)wherein Ar1 represents an aromatic residue; Ar2 represents a bivalent or trivalent aromatic residue; n represents an integer of 2 or 3 comprises reacting an arylsulfonamide alkali metal salt of general formula (2) Ar1 --SO2 NH.B (2)wherein B represents an alkali metal with an aromatic isocyanate compound of general formula (3) Ar2 --(NCO)n (3)in at least one solvent selected from the class consisting of acetonitrile, acetone, methyl ethyl ketone, diethyl ketone, methyl isobutyl ketone, tetrahydrofuran, ethyl acetate, and butyl acetate and containing 1 to 10 weight % of water in a state of suspension being maintained throughout the reaction and eliminating the alkali metal from the resulting arylsulfonylureide compound alkali metal salt in the same solvent.