Showing papers on "Methyl isobutyl ketone published in 1979"
TL;DR: In this article, the course of liquid-induced crystallization of a bisphenol A-derived polycarbonate was investigated using acetone, methyl propyl ketone and xylene as swelling agents, and a distinct separation of the diffusion and crystallization fronts was observed, changes in the distance between these two fronts having been determined for various swelling temperatures.
Abstract: The course of liquid-induced crystallization of a bisphenol A-derived polycarbonate was investigated using acetone, methyl propyl ketone, methyl isobutyl ketone, and xylene as swelling agents. It was found that above a certain temperature, characteristic of a given polycarbonate–swelling agent system, the diffusion process takes place with the formation of a sharp boundary. The velocity of motion of the diffusion front was determined at various temperatures, and these data were then used to calculate the apparent diffusion coefficients and diffusion activation energies for the different swelling liquids employed. Moreover, a distinct separation of the diffusion and crystallization fronts was observed in the systems investigated, changes in the distance between these two fronts having been determined for various swelling temperatures. The above phenomenon was used to determine the experimental conditions making possible the characterization of a crystallization process not controlled by the diffusion of the swelling agent into the sample. The dependence of half-times of crystallization on temperature was determined based on crystallization kinetics studies performed by means of a light depolarization technique.
31 citations
TL;DR: Exposure to a combination of the same doses of MEK and MIBK produced a consistent increase in extra responses during delay and a concomitant decrease in response times, compared to the effects of the individual gases.
Abstract: Acetone, methyl ethyl ketone (MEK) and methyl isobutyl ketone (MIBK) were evaluated for effects on a delayed match-to-sample discrimination task in the juvenile baboon. The animals were exposed to 1/2 the threshold limit value (TLV) of each gas for 24 hr per day during a 7-day period. They were also exposed to a combination of MEK and MIBK at the same exposure concentrations. Each exposure condition affected accuracy of performance minimally but resulted in increased and decreased extra responses during the delay intervals. Response times were slowed under acetone, MEK or MIBK. In contrast to the effects of the individual gases, exposure to a combination of the same doses of MEK and MIBK produced a consistent increase in extra responses during delay and a concomitant decrease in response times. Changes in tissue uptake and metabolism are suggested as possible mechanisms to explain this observation.
23 citations
TL;DR: A critical study of the solution conditions and other parameters affecting the reliability of the ammonium pyrrolidinedithiocarbamate-methyl isobutyl ketone (APDC-MIBK) extraction system for Ag, Cd, Co, Cr, Cu, Fe, Mn, Ni, and Pb was made as discussed by the authors.
Abstract: A critical study of the solution conditions and other parameters affecting the reliability of the ammonium pyrrolidinedithiocarbamate-methyl isobutyl ketone (APDC-MIBK) extraction system for Ag, Cd, Co, Cr, Cu, Fe, Mn, Ni, and Pb was made. The following parameters were investigated in detail: pH of the aqueous phase prior to extraction, amount of APDC added to the solution following pH adjustment, the length of time needed for complete extraction and the time-stability of the chelate in the organic phase. Except for Ag and Cr which were quantitatively extracted only in a very narrow pH range (1.0-2.0 and 1.8-3.0, respectively), and Cd and Pb which were stable in the extracted MIBK phase only for 2-3 hrs, the solution conditions for quantitative extraction were not critical for the other metals. Simultaneous extraction of all the metals except Cd and Pb was also investigated, Good recoveries (100±10%) were obtained for a number of spiked raw, treated and distributed drinking water samples covering...
19 citations
TL;DR: The analytical performance of a chelation/extraction procedure for concentrating trace metals from natural water samples has been investigated in this article, where the chelates were found to be stable in the organic phase for at least ten days.
Abstract: The analytical performance of a chelation/extraction procedure for concentrating trace metals from natural water samples has been investigated. The metals (Cd, Co, Cu, Ni, Pb, Zn), chelated with ammonium pyrrolidine dithiocarbamate, were concentrated by solvent extraction in methyl isobutyl ketone at a sample pH of 4; the organic phase was analyzed by flame atomic absorption spectrophotometry. Sensitivity of the method tested was adequate for surface waters and precision proved to be good. The chelates were found to be stable in the organic phase for at least ten days. In the two rivers studied, the recovery of spiked metals proved to be independent of sampling stations but slightly dependent on sampling dates; this latter dependence suggests the existence of weak matrix effects. No significant interferences from linear alkyl sulphonate (1 mg/l) or from humic acid (3mgC/l) were detected.
17 citations
TL;DR: Bismuth concentrations as low as 10 ng g-1 in 100-mg samples of geological materials can be determined by atomic absorption spectrometry with electrothermal atomization as mentioned in this paper.
15 citations
TL;DR: Recoveries of molybdenum from fortified samples ranged from 92.0 to 98.9% and the limits of detection on the flame and graphite furnace were 10 and 2 ng/mL, respectively.
Abstract: A method is presented for determining molybdenum in plant tissue and blood plasma by flame and flameless atomic absorption spectroscopy (AAS). The samples are digested with HNO3-HCIO4, and the metal is separated by chelation, extracted into methyl isobutyl ketone, and analyzed by AAS. Recoveries of molybdenum from fortified samples ranged from 92.0 to 98.9%. The limits of detection on the flame and graphite furnace were 10 and 2 ng/mL, respectively.
12 citations
TL;DR: An atomic absorption spectrometric method was reported for the determination of cobalt, nickel, and copper in a variety of geological materials including iron and manganese-rich, and calcareous samples as discussed by the authors.
12 citations
TL;DR: In this paper, conditions for the formation and extraction of thiocyanate complexes of osmium and ruthenium are reported, and the molar absorptivities are 1.71 × 104 l m mol-1 cm-1 for the Osmium complex at 620 nm and 5.5 × 103 l mor-1cm-1
12 citations
11 citations
TL;DR: In this article, the determination or cadmium, cobalt, copper, nickel and lead after extraction with tetramethylenedithiocarbamate into various solvents is achieved by injection of 50-μl aliquots of extract by pulse nebulization into an air-acetylene flame.
11 citations
TL;DR: In this article, a detailed study of the possible interferences from 123 representative organic compounds is described; 61 compounds interfered (when present in amounts of 0.1 g in the original sample).
TL;DR: In this paper, an improved curcumin method was developed using a 20 percent v/v 2-ethyl-l, 3-hexanediol, a boron complexing agent, in methyl isobutyl ketone as an extracting solvent.
Abstract: In the present study, an improved curcumin method has been developed using a 20 percent v/v 2-ethyl-l, 3-hexanediol, a boron complexing agent, in methyl isobutyl ketone as an extracting solvent. A 5-cm cylindrical quartz cell is
Patent•
30 Jan 1979
TL;DR: In this paper, a method to obtain colorless and odorless polyhydric alcohols from crude polydrugs obtained from compounds by-produced in the production of 4,4-dimethyl-1,3-dioxane, by extracting the crude alcohol with methyl isobutyl ketone in the presence of water.
Abstract: PURPOSE:To obtain colorless and odorless polyhydric alcohols from crude polyhydric alcohols obtained from compounds by-produced in the production of 4,4-dimethyl-1,3-dioxane, by extracting the crude alcohol with methyl isobutyl ketone in the presence of water.
TL;DR: It is observed that 2-hydroxyacetophenone oxime can be used for the quantitative extraction of nickel in the pH range 6.6-7.8 into methyl isobutyl ketone and Beer's law is obeyed over the range 1-6 ppm.
Patent•
07 Jun 1979
TL;DR: In this paper, an organic solvent, substantially insoluble in water, and capable of dissolving the aimed compound, particularly hexane, heptane, toluene, benzene and/or methyl isobutyl ketone, may be used as the organic solvent.
Abstract: PURPOSE: To obtain the titled compound having a large crystal form in reacting diisopropylbenzene dihydroperoxide, etc with a sulfite in the presence of an alkali efficiently, by carrying out the reaction in the presence of an organic solvent while removing the organic solvent to the outside of the system CONSTITUTION: Diisopropylbenzene dihydroperoxide or (2-hydroxy-2-propyl) cumene hydroperoxide or both are reacted with a sulfite in the presence of an alkali and an organic solvent while removing the organic solvent to the outside of the system by the azeotropic mixture thereof with water in the reaction, preferably the azeotropic mixture with water under reduced pressure, to give the aimed compound useful as a raw material for peroxides, eg a radical polymerization initiator, industrially and advatageously An organic solvent, substantially insoluble in water, and capable of dissolving the aimed compound, particularly hexane, heptane, toluene, benzene and/or methyl isobutyl ketone, may be used as the organic solvent COPYRIGHT: (C)1983,JPO&Japio
TL;DR: A one-tube sample preparation method for blood lead determination which is relatively simple to perform and which does not require background correction for matrix effects is described.
Abstract: This paper describes a one-tube sample preparation method for blood lead determination which is relatively simple to perform and which does not require background correction for matrix effects The red cells are lysed with a dilute potassium cyanide solution and heat A citrate buffer is added, and the solution is then extracted with ammonium pyrrolidine dithiocarbamate and methyl isobutyl ketone An aliquot of the MIBK layer is applied to a carbon rod atomizer and the peak at 2170 nm is measured The method demonstrates an overall in-run reproducibility of 139 µg/100 mL blood standard deviation, a between-run standard deviation of 227 µg/100 mL blood and a sensitivity of 0012 µg/mL/1% nm
01 Jun 1979
TL;DR: In this article, the effects of water-phase pH on the extraction equilibria of weakly acidic phenols were studied in a series of pH-controlled batch extractions of phenol, resorcinol, and hydroquinone into diisopropyl ether (DIPE) and methyl isobutyl ketone (MIBK).
Abstract: Condensate water samples from two typical coal-conversion processes were analyzed for phenols by gas chromatography-mass spectrometry and high-performance liquid chromatography. Significant amounts of phenol, dihydroxybenzenes and the trihydroxybenzene phloroglucinol were found. The presence of a trihydroxybenzene is particularly important as trihydroxybenzenes are extremely resistant to biological oxidation. The effects of water-phase pH on the extraction equilibria of the weakly acidic phenols were studied in a series of pH-controlled batch extractions of phenol, resorcinol, and hydroquinone into diisopropyl ether (DIPE) and hydroquinone into methyl isobutyl ketone (MIBK). The equilibrium distribution coefficient K/sub D/ decreased sharply in the pH range typical of condensate waters, 8.7-9.8, which is also the range of the pK/sub a/'s of the phenols. A simple model combining the acid ionization and the phase distribution equilibria fit the data well. Batch extractions of di- and trihydroxybenzenes into MIBK and DIPE showed MIBK to be clearly a better solvent than DIPE. The distribution coefficients in MIBK were an order of magnitude greater than those in DIPE, some of which were much less than unity. DIPE is currently used in the Phenosolvan process to extract phenol from coke-oven and coal-conversion effluent waters. With the K/sub D/'s measured in this work, calculationsmore » showed that the Phenosolvan process, as currently run, will not remove polyhydroxybenzenes from alkaline water solution to the levels required for further treatment, recycle or discharge of the condensate waters.« less
TL;DR: In this article, a procedure for determination of small amounts of silver in copper ores and processed products is proposed, where samples are dissolved in a Teflon bomb in a mixture of hydrofluoric and nitric acids, then evaporated in the presence of nitric and boric acids.
Abstract: A procedure is proposed for determination of small amounts of silver in copper ores and processed products. The samples are dissolved in a Teflon bomb in a mixture of hydrofluoric and nitric acids, then evaporated in the presence of nitric and boric acids. Silver is extracted from the sample solution with a solution of triphenylphosphine in methyl isobutyl ketone, then determined by atomic-absorption spectrophotometry. The method is precise and accurate. The relative standard deviation for a silver content of 10−4% is about 4%.
TL;DR: In this article, the effect of surfactants, condensed phosphates, soap, EDTA, NTA, citric acid, oil and Alamine-336 on the fluorimetric determination of uranium in a 5-ml aqueous sample extracted with methyl isobutyl ketone after addition of saturated calcium nitrate or 1N acid-deficient saturated aluminium nitrate salting-out solutions has been established.
Abstract: The effect of surfactants, condensed phosphates, soap, EDTA, NTA, citric acid, oil and Alamine-336 on the fluorimetric determination of uranium in a 5-ml aqueous sample extracted with methyl isobutyl ketone after addition of saturated calcium nitrate or 1N acid-deficient saturated aluminium nitrate salting-out solutions has been established. The error produced by these compounds, even at concentrations up to 500 mg/l, does not exceed ±10%, except for anionic LAS-type detergent, which at above the 50 mg/l level forms stable emulsions after extraction from solutions containing the acid-deficient aluminium nitrate salting-out reagent. Up to 1 hour of standing time after extraction may be required for the emulsions to break. The detection limit for uranium is 1.1μg/l (2s).
Patent•
02 May 1979
TL;DR: In this paper, the authors proposed a method to obtain a by-product diisobutyl ketone fraction of high quality which contains acidic impurities by the alkali treatment of a residue after removal of a product from a reaction mixture through the distillation in the production of methyl isomethaine.
Abstract: PURPOSE:To obtain a by-product diisobutyl ketone fraction of high quality which contains acidic impurities a little, by the alkali treatment of a residue after removal of a product from a reaction mixture through the distillation in the production of methyl isobutyl ketone. CONSTITUTION:In the production of methyl isobutyl ketone from acetone and/or isopropanol by aldol condensation, hydrogenation, etc., alkali treatment is carried out when a by-product diisobutyl ketone fraction is isolated after removing a light fraction, such as methyl isobutyl ketone, etc. from a reaction product by distillation. The diisobutyl ketone fraction contains diisobutyl ketone as a principal component and small amounts of 4,6-dimethyl-2-heptanone, diisobutyl carbinol, etc. In the alkali treatment, 0.1-10wt.% aqueous solution of NaOH, etc. is preferably used. The aqueous solution is preferably used in an amount of 0.1-30 parts by volume per part by volume of the residue or diisobutyl ketone fraction to be treated.
Journal Article•
TL;DR: A gas chromatographic method of determination of methyl isobutyl ketone, methyl isOButyl carbinol, acetone, toluene and o-xylene has been elaborated.
Abstract: A gas chromatographic method of determination of methyl isobutyl ketone, methyl isobutyl carbinol, acetone, toluene and o-xylene has been elaborated Those compounds have been best separated on the column containing 10% Carbowax 20 M on Chromosorb W Air samples were collected by passing the examined air through charcoal tubes and by consequent desorption of adsorbed compounds with carbon disulfide Activated charcoal used in tests has been found to adsorb (by weight) 15% of the determined solvents