Methylisobutyl ketone

The sample to be analyzed can be dissolved in an organic solvent, xylene or methylisobutyl ketone. Generally, for reasons of reproducibility and because of matrix effects (the surroundings affect the droplet size and therefore the effectiveness of the nebulization process), it is preferable to mineralize the sample in H2SO4, evaporate it and conduct the test in an aqueous environment. 

As a symmetrical ketone, acetone is a reactive compound with many synthetic uses. Among the important chemicals based on acetone are methylisobutyl ketone, methyl methacrylate, ketene, and diacetone alcohol. 

Mesityl Oxide. This is an alpha-beta unsaturated ketone of high reactivity. It is used primarily as a solvent. It is also used for producing methylisobutyl ketone. 

Mesityl oxide is produced by the dehydration of acetone. Hydrogenation of mesityl oxide produces methylisobutyl ketone, a solvent for paints and varnishes ... 

In almost all theoretical studies of AGf , it is postulated or tacitly understood that when an ion is transferred across the 0/W interface, it strips off solvated molecules completely, and hence the crystal ionic radius is usually employed for the calculation of AGfr°. Although Abraham and Liszi [17], in considering the transfer between mutually saturated solvents, were aware of the effects of hydration of ions in organic solvents in which water is quite soluble (e.g., 1-octanol, 1-pentanol, and methylisobutyl ketone), they concluded that in solvents such as NB andl,2-DCE, the solubility of water is rather small and most ions in the water-saturated solvent exist as unhydrated entities. However, even a water-immiscible organic solvent such as NB dissolves a considerable amount of water (e.g., ca. 170mM H2O in NB). In such a medium, hydrophilic ions such as Li, Na, Ca, Ba, CH, and Br are selectively solvated by water. This phenomenon has become apparent since at least 1968 by solvent extraction studies with the Karl-Fischer method [35 5]. Rais et al. [35] and Iwachido and coworkers [36-39] determined hydration numbers, i.e., the number of coextracted water molecules, for alkali and alkaline earth metal... 

Morris [814] separated microgram amounts of vanadium, chromium, manganese, iron, cobalt, nickel, copper, and zinc from 800 ml of seawater by precipitation with ammonium tetramethylenedithiocarbamate, and extraction of the chelates at pH 2.5 with methylisobutyl ketone. Solvent was removed from the extract, the residue was dissolved in 25% nitric acid, and the inorganic residue was dispersed in powdered cellulose. The mixture was pressed into a pellet for X-ray fluorescence measurements. The detection limit was 0.14 pig or better when a 10 min counting period was used. 

The best way to take advantage of the organic solvent effect without simultaneously diluting the sample is by employing solvent extraction. By this method the element to be analyzed can actually be concentrated and a solution of the element is obtained in essentially pure organic solvent. One of the most commonly used systems involves formation of the metal chelate with ammonium 1-pyrro-lidinecarbodithioate (APDC) and then extracting this into methylisobutyl ketone (MIBK). APDC chelates of many elements form and extract into MIBK from acid solution. 

Paper chromatography using Whatman No. 1 paper was once used to determine the homogeneity of halcinonide. 60 Twenty percent formamide in methanol comprises one stationary phase and methylisobutyl ketone-formamide (20 1) is the mobile phase. A second solvent system uses 25% propylene glycol-chloroform as the stationary phase and toluene saturated with propylene glycol as the mobile phase. 

Rhenium can be analyzed by various instrumental techniques that include flame-AA, ICP-AES, ICP-MS, as well as x-ray and neutron activation methods. For flame-AA analysis the metal, its oxide, or other insoluble salts are dissolved in nitric acid or nitric-sulfuric acids, diluted, and aspirated directly into nitrous oxide-acetylene flame. Alternatively, rhenium is chelated with 8-hydroxy quinoline, extracted with methylisobutyl ketone and measured by flame-AA using nitrous oxide-acetylene flame. 

In the single publication which describes this device (01), tests are reported for a 6-in.-diameter tower with the system acetic acid-methylisobutyl ketone-water, ketone dispersed. Extraction rates are expressed... 

In a 40-mm.-diameter column (Cl) with 3-in. plate spacing and %4-in. holes whose total cross section was about 6% of the column cross section, and with the system acetic acid-methylisobutyl ketone-water, ketone dispersed, the best extraction rates occurred at a total liquid flow of 35.6 cu. ft./(hr.)(sq. ft.), 29 cycles/min., and 4-mm. amplitude. The HETS was 10 in., corresponding to a total throughput/volume of a theoretical stage of 42.1 hr.-1. Similarly in a 1.5-in. column (B2) with plates on a 1-in. spacing and containing ) 2-in. holes whose area was 23% of the column cross section, pulsed at 28 cycles/min., 6-mm. amplitude, with the same system, the HETS was 2.59 in. at a total liquid flow... 

MIBK - Methylisobutyl ketone. Solvent used in some cements and primers. 

Single Stage and Cross Current Extraction of Acetic Add from Methylisobutyl Ketone with Water... 

Note TBPO, tributylphosphine oxide. TOPO, trioctylphosphine oxide. TPPO, triphenylphosphine oxide, acac, acetyl acetone. HDEHP, di(2-ethylhexyl)phosphoric acid. MIBK, methylisobutyl ketone. DMDOHEMA, N,iV-diniethyl-iV,iV-dioctylhexylethoxymalonamide. 

A number of procedures for the determination of metals and biological samples call for the extraction of the metal with an organic chelating agent in order to remove interferences and concentrate the metal to enable detection of low levels. The urine or blood sample may be first subjected to wet ashing to enable extraction of the metal. Beryllium from an acid-digested blood or urine sample may be extracted by acetylacetone into methylisobutyl ketone prior to atomic absorption analysis. Virtually all of the common metals can be determined by this approach using appropriate extractants. 

The availability of strongly chelating extractant reagents for a number of metals has lead to the development of procedures in which the metal is extracted from minimally treated blood or urine and then quantified by atomic absorption analysis. The metals for which such extractions can be used include cobalt, lead, and thallium extracted into organic solvent as the dithiocarbamate chelate, and nickel extracted into methylisobutyl ketone as a chelate formed with ammonium pyrro-lidinedithiocarbamate. 

An indirect AAS method was described for EDTA in the antibiotic streptomycin [42]. The method involved formation of the Ni(II) complex with EDTA, release of complexed Ni(II) by pH adjustment, and subsequent determination of Ni(II) by AAS. EDTA was also determined through its masking effect on the extraction of copper oxinate into methylisobutyl ketone at pH 6.5. The decrease in AAS signal of Cu(II) was linearly proportional to the EDTA concentration [43]. 

Ketones are extensively used as solvents and extracts in a number of worldwide industries. The most widely used ketones are acetone, methylethyl ketone, methylisobutyl ketone, and cyclohexanone. The interaction of methylethyl ketone with other chemicals, such as n-hexane, potentiates neurotoxicity in mammals and demonstrates solvent-induced neuropathy. High concentrations of methylethyl ketone in workplace air caused depression, narcosis, and numbness of the extremities.43... 

ICP-AES=inductively coupled plasma-atomic emission spectrometry Mg(N03)3=magnesium nitrate MIBK=methylisobutyl ketone MS=mass spectrometry PIXE=proton-induced X-ray emission spectrometry XRF=X-ray fluorescence analysis WM-AES=wavelength-modulated atomic emission spectrometry... 

Cvetkovic and coworkers [74] evaluated a mixed Ni and Sr nitrates matrix modifier for the determination of Se in wines by Zeeman ET-AAS. Samples were heated on a boiling water bath with small amounts of HNO3 and H2O2. To eliminate interferences, especially sulfates and phosphates, Se was complexed with APDTC and extracted into methylisobutyl ketone (MIBK) and the graphite furnace temperature program was optimized for both aqueous and organic solutions. Selenium concentrations up to 0.93 pg l-1 were detected in wines from the Republic of Macedonia. 

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