Showing papers on "Methyl isobutyl ketone published in 1978"

Analysis for nickel in plasma and urine by electrothermal atomic absorption spectrometry, with sample preparation by protein precipitation.

Abstract: We describe and evaluate a method for determining nickel in plasma and urine by atomic absorption spectrometry. Proteins are precipitated with trichloroacetic acid and sulfuric acid; ammonium pyrrolidinedithlocarbamate is used as the chelating agent for nickel, and methyl isobutyl ketone as extraction solvent. The results were compared with results obtained by the acid-digestion technique for removing proteins and other organic substances. Analyses for both plasma and urine were better by the present procedure. The mean and standard deviation for nickel in plasma from 15 healthy individuals was 2.13 +/- 0.58 microgram/liter by this method. For nickel in urine from 15 healthy men the mean and standard deviation was 4.45 +/- 1.9 microgram/liter. The coefficient of variation for plasma was 11.9%, and for urine 12.2% in 10 analyses of the same plasma and urine with the protein-precipitation procedure, as compared with 26.0 and 38.2%, respectively, by the acid-digestion technique.

Processing method for magnetic powder

Abstract: PURPOSE: To improve a dispersion property in a binder by adding monomer such as metacrylic acid and others, acryl series monomer and copolymer starter and precipitate to a water medium containing a dispersed magnetic powder and thereafter by covering the powder surface with those components. CONSTITUTION: A monomer containing 10 mole % of metacrylic acid, 45 mole % of metacrylic methyl and 45 mole % of acrylic acid ethyl is primarily added to 10 part of γ-Fe 2 O 3 magnetic powder. Successively, karium sulfide 0.003 part, sodium sulfate 0.5 part and water 100 part are added to the above composition to heat and provide a repolymer for them, thereafter being washed, filtered and dried. Thereafter this powder is mixed together with vinyl chloride - vinyl acetate - vinyl alcohol copolymer and methyl isobutyl ketone - toluen mixed solvent to be kneaded together and is coated and dried on a polyester film. By such a process, a magnetic tape with a great retangular rate can be prepared. COPYRIGHT: (C)1980,JPO&Japio

A new personal sampler for organic vapors

Abstract: This paper describes the evaluation of a new personal sampler for organic vapors which is totally different from traditional sampling techniques using pumps and adsorption tubes. Sampling of organic vapors is effected by collection on an adsorption substrate contained within a small passive sampler worn by the worker. The collection element is removed from the sampler and subsequently analyzed for organic vapors. The results are equated with the time-weighted-average concentration of contaminants in air. This new sampling device circumvents inherent errors generally associated with sampling pumps and tubes; e.g., changes in pumping rates and variable pressure drops across adsorption tubes. Applications of the sampler were demonstrated on various concentrations of benzene, methyl isobutyl ketone, isooctane, butyl acetate, methyl chloroform, trichloroethylene, butanol and solvent mixtures. Variables studied included the effects of temperature, charcoal lot, and air velocities. In addition, the occurrence of "breakthrough" and effect of time on sample stability were investigated.

Application of a Coagulated Mixture Prepared from Finely Divided Cation and Anion Exchange Resins to the Enrichment of Copper (II)

Abstract: Mutual coagulation takes place, when a suspension of finely divided cation exchanger is added to that of anion exchanger. The resulting mixed resin is bulky and easily separated from the solution by filtration. A rapid and selective collection of a trace amount of copper(II) ion was carried out by the combined use of mixed resin and 8-quinolinol-5-sulfonic acid (H2qs). The copper(II) collected on the mixed resin in the form of [Cu(qs)2]2− was brought into solution from the resin with ethylenediaminetetraacetate, converted into copper(II)–diethyldithiocarbamate, extracted into methyl isobutyl ketone, and determined by atomic absorption spectrometry. The method was satisfactorily applied to the determination of a trace amount of copper(II) in well water.

Extraction of palladium and platinum with trioctylphosphine oxide (topo) in various solvents from hydrochloric and hydrobromic acid media

Abstract: The extraction of palladium and platinum with trioctylphosphine oxide (TOPO) in cyclohexane, chloroform, methyl isobutyl ketone (MIBK) and 2,2′-dichlorodiethyl ether (DCDE) from hydrochloric and hydrobromic acids in dependence on the concentration of the acids and the extractant has been investigated. The obtained relation have been discussed and the possibilities of the separation of palladium, platinum, gold and their simultaneous extraction have been pointed out.

Fluorination of methyl ketones

Abstract: Methyl ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone react with vaporized aqueous HF in the vapor phase at about 190° C.-400° C. to make the corresponding 2,2-difluoroalkanes.

Determination of microgram amounts of tellurium in steels by atomic absorption spectrometry

Abstract: A solvent extraction procedure has been developed for the determination of tellurium in all types of steel. After dissolution, the sample is extracted with trioctylphosphine oxide-methyl isobutyl ketone. The extract is then nebulized directly into the atomic absorption burner flame. This method requires 25 minutes and can determine as low as 2 parts per million level tellurium.

Spectrophotometric Study of 1, 3-Cyclohexanedione Bisthiosemicarbazone Monohydrochloride -Bi (III) Complex. Determination of Bi (III)

Abstract: The spectrophotometric study was made of red-violet 1, 3-cyclohexanedione bis-thiosemicarbazone-Bi (III) in an acidic dimethylformamide-water solution (λmax = 540 nm, ∊ = 3.3 × 10−4 1. mol−1. cm−1, stoichiometry 3:1, apparent stability constant (6.0 × 1010). A new method for the spectrophotometric determination of Bi (III) is proposed for concentrations between 0.7 and 7.4 ppm. The relative error (95 % confidence level) is 0.5 % for 3.7 ppm of Bi (III). The extraction with methyl isobutyl ketone of the red-violet complex was also studied spectrophotometrically (λmax = 550 nm, ∊ = 3.34 × 104 1. mol−1.cm−1, stoichiometry 2:1). A new method for the extraction-spectrophotometric determination of Bi (III) is proposed for concentrations, in aqueous phase, between 0.2 and 1.2 ppm. The relative error (95 % confidence level) is 0.8 % for 0.9 ppm of Bi (III).

Atomic Absorption Spectroscopic Determination of Lead Extracted from Acid-Solubilized Tissues

Abstract: A method is presented for determining lead in a variety of tissues. Lyophilized samples are solubilized with nitric acid at room temperature in glass screw-cap culture tubes. Following neutralization with sodium hydroxide and sodium bicarbonate, the lead is extracted into methyl isobutyl ketone as the pyrrolidine dithiocarbamate complex and analyzed by flame atomic absorption spectrophotometry. Brain, heart, liver, lung, and spleen gave recoveries ranging from 92 to 102% with standard deviations of less than 8%. Aorta, kidney, and rib were unsuitable for analysis by this method. A large number of samples can be analyzed without specialized equipment or intricate experimental steps. The detection limit is 35 ng/g tissue (wet weight) and sensitivity is approximately 140 ng/g tissue (wet weight).

Determination of organosilicon compounds in water by atomic absorption spectroscopy

Abstract: An extraction technique is described for the determination of ppm concentrations of both hydrophobic and hydrophilic methylsiloxane compounds in water, based on a single extraction with a mixed solvent of (1∶1) l-pentanol and methyl isobutyl ketone followed by the determination of the silicone compounds extracted into the mixed solvent by atomic absorption spectroscopy. The method is applicable over the concentration range 0.3–30 ppm Si. Standard deviation in the case of 10 ppm Si is 0.313.

Solvent extraction of gold(III) with 1-phenyl-3-methyl-4-trifluoroacetylpyrazolone-5

Abstract: A simple, rapid and selective separation procedure of gold based on its extraction with 1-phenyl-3-methyl-4-trifluoroacetylpyrazolone-5 has been developed. The dependence of the distribution ratio of gold on the pH of aqueous solutions, concentration of hydrochloric, nitric and perchloric acids and the organic solvents has been investigated. Decontamination factors for a number of metal ions with respect to gold are reported. Excellent separation of gold is obtained from many elements including noble metals. Citrate, cyanide, iodide, thiosulfate and thiourea completely mask gold, whereas oxalate does not interfere. Solutions of 1 M HCl, 0.2 M KCN, and the buffer of pH 0.8 readily strip gold from the organic phase. Some useful analytical applications of this procedure are discussed.

Distillation process for recovery of methyl isobutyl ketone

Abstract: There is disclosed an azeotropic distillation process for separating toluene from methyl isobutyl ketone (MIBK) in a spent liquor mixture. A toluene azeotrope former, preferably methanol, is added to the liquor in an amount sufficient to form an azeotrope with all of the toluene present in the mixture. The methanol is added in an amount of at least about 2.62, typically an excess amount of about 3.4 to about 6.3 parts by weight of methanol per 1.0 part by weight of toluene. The resulting azeotrope of methanol and toluene is then separated by distillation from the MIBK. The methanol may be subsequently recovered from the toluene by extraction with water. Other toluene azeotrope formers may be utilized.

Recovery of hydroquinone

Abstract: Hydroquinone is obtained in greater than 95 percent yield through a nonaqueous recovery process compatible with the methyl isobutyl ketone (MIBK) based diisopropylbenzene dihydroperoxide isolation process Hydroquinone, from the Hock-splitting reaction, is precipitated (after most of the reaction solvent is distilled off), separated, repulped in acetone, crystallized and separated again The supernatant from the first separation step contains hydroquinone along with tars This stream is subjected to a purification process comprising a series of distillation and extraction steps so that the hydroquinone in that stream can be recycled back into the process

Extraction and atomic-absorption spectrometric determination of traces of bismuth with zinc dibenzyldithiocarbamate in aluminium alloys and solder alloys

Abstract: A sensitive method for the extraction and atomic-absorption spectrometric determination of bismuth with zinc dibenzyldithiocarbamate (ZnDBC) has been developed for aluminium alloys and solder alloys. Bismuth is extracted from relatively strong acidic solution into methyl isobutyl ketone (MIBK) as BiDBC complex and its concentration is determined by spraying the MIBK extract into an air-acetylene flame. Iron and copper up to 1 mg resp. 100 μg did not interfere with the extraction of bismuth in the range of 0–80 μg. The limit of detection was about 0.12 ppm in MIBK.

An automated system for the determination of lead in blood, manganese in urine and nickel in waste water

Abstract: An automated system has been developed to analyze lead in blood, manganese in urine and nickel in waste water at a rate of 20 to 30 samples per hour. The analysis is based on direct chelation without digestion, extraction into methyl isobutyl ketone and flame atomic absorption spectrophotometry. The applicability of the system in the field of occupational and environmental medicine is discussed.

Extraction of methacrylic acid

Abstract: PURPOSE:To extract methacrylic acid from a mixture containing methacrylic acid efficiently and to separate it easily after the extraction, using methyl isobutyl ketone having a large partition coefficient as a solvent.

Flameless atomic absorption spectroscopic determination of heavy metals in whole-fish samples

Abstract: Flameless atomic absorption spectroscopy with a carbon rod atomizer was used to determine lead, cadmium, and chromium in whole-fish samples. Samples were dry-ashed, and the metals were separated by solvent extraction with ammonium pyrrolidine dithiocarbamate in methyl isobutyl ketone, and then back-partitioned into an aqueous acid solution for analysis. The back-partitioning step allows a direct comparison of sample solutions with aqueous solutions of the standard. Recoveries of the metals from fortified samples averaged 91% (+/-9.6) for lead and 100% (+/-5.6) for chromium at the 0.1-1 ppm level, and 100% (+/-13.3) for cadmium at the 0.01-0.1 ppm level.

Application of a coagulated mixture prepared from finely divided cation and anion exchange resins to the enrichment of copper(ii)

Abstract: Mutual coagulation takes place, when a suspension of finely divided cation exchanger is added to that of anion exchanger. The resulting mixed resin is bulky and easily separated from the solution by filtration. A rapid and selective collection of a trace amount of copper(II) ion was carried out by the combined use of mixed resin and 8-quinolinol-5-sulfonic acid (H2qs). The copper(II) collected on the mixed resin in the form of [Cu(qs)2]2− was brought into solution from the resin with ethylenediaminetetraacetate, converted into copper(II)–diethyldithiocarbamate, extracted into methyl isobutyl ketone, and determined by atomic absorption spectrometry. The method was satisfactorily applied to the determination of a trace amount of copper(II) in well water.

Synthesis and aqueous recovery of hydroquinone

Abstract: Hydroquinone having a purity greater than 99 percent is isolated through an aqueous recovery scheme compatible with the methyl isobutyl ketone based diisopropylbenzene dihydroperoxide isolation process. Hydroquinone. from the Hock-splitting reaction, is extracted into water while the impurities are concentrated in a distillation tower. Phase separation of the distillation tower bottoms affords an efficient separation of the hydroquinone from the organic impurities. Concentration, crystallization, and solid liquid separation (centrifugation) of the aqueous phase yields a wet hydroquinone cake which, upon recrystallization from acetone. yields high purity hydroquinone.

Nickel and cobalt sepn. from aq. acid soln. - by extn. with thiocyanate contg. methyl isobutyl ketone with less loss of thiocyanate ions

Abstract: Method for solvent utractial using thiocyanate ions to separate one metal from another in aq ueous soln. comprises adding to the soln. an inorganic acid to inhibit almost completely the ionisatial of the thiocyanate to thiocyanic acid. Hydrocyanic acid is removed from the aq. soln. using a water immiscible organic solvent, thus, minimising the loss of strength in thiocyanate ions. Process is used esp. for the sepn. of Co and Ni in acid soln. It can also be used to separate Be and Al; or Hf and Zr. The closed cycles giving thiocyanate and acid recovery cheapn the process.