Acetone isopropyl alcohol system

Another system was studied with x-rays, which should give results similar to when y-rays are used. In the acetone-isopropyl alcohol system Rabani and Stein (57) reported G(H2) as function of pH, acetone, and isopropyl alcohol concentrations. They report GH = 0.55 and Ge = 2.65 at pH 2-4. 

If we apply (26.73) to the system acetone + chloroform discussed above we find that the term - 2nj In rj always determines the sign of 5. The excess entropy in this case is then associated mainly with the loss in the number of orientations of the monomolecules. Another similar case is that of methanol + carbon tetrachloride (c/. fig. 24.5). On the other hand we must notice that for the systems acetone + ethanol and acetone + isopropyl alcohol the excess entropy is positive... 

A yield of about 95% of theoretical is achieved using this process (1.09 units of isopropyl alcohol per unit of acetone produced). Depending on the process technology and catalyst system, such coproducts as methyl isobutyl ketone and diisobutyl ketone can be produced with acetone (30). 

Stratifying water systems for selective extraction of thiocyanate complexes of platinum metals have been proposed. The extraction degree of mthenium(III) by ethyl and isopropyl alcohols, acetone, polyethylene glycol in optimum conditions amounts to 95-100%. By the help of electronic methods, IR-spectroscopy, equilibrium shift the extractive mechanism has been proposed and stmctures of extractable compounds, which contain single anddouble-chai-ged acidocomplexes [Rh(SCN)J-, [Ru(SCN)J, [Ru(SCN)J -have been determined. Constants of extraction for associates investigated have been calculated. 

Complexes of N-N bonded dinitrogen dioxide, such as depicted in pathway B of Scheme 5, would appear to be necessary in order to effect the formation of the N-N bond. This has been treated theoretically as a metal promoted reductive coupling of 2 NO to form a hyponitrite complex (79). The Cu Tp112) system was also shown to catalyze NO oxidations of benzyl and isopropyl alcohol to benzaldehyde and acetone (Eq. (37)). Electrospray mass spectrometry indicated that higher... 

In 1992, industrial wastewater containing isopropyl alcohol and acetone from the Kennedy Air Force Base was treated using at 5-gpm Perox-Pure unit. Total O M costs for the system were 3.60 per 1,000 gallons of wastewater treated. These costs included 2.00 for electricity priced at 0.06 per kW-hour, 0.60 for hydrogen peroxide priced at 0.35 per pound, and 1.00 for maintenance (D10057S, p. 59 60 D19079Y, p. 3-21 D17231G, p. 410). 

A systematic study has been developed by Christopoulou and Perkins (78). They employed three different types of detectors (differential refractometer, variable wavelength detector set at 205 or 232 nm, and infrared detector at 5.72 /zm) and three commercially packed columns (I, LC-Si, 250 X 4.6-mm ID, 5-/zm particle size II, LC-18, 250 X 4.6-mm ID, 5-/zm particle size III, LC-18, 150 X 4.6-mm ID, 5-/zm particle size). The various mobile phases used were system I, 1.5% isopropyl alcohol (IPA) in hexane system II, acetonitrile/acetone (1 1) system III, acetonitrile (spectra) system IV, acetonitrile/methylene chloride (3 1). Columns I and II were used with solvent systems I and II, respectively, and refractometry was the mode of detection. Column III was used with solvent system III and UV detection at 205 or 232 nm, as well as with solvent system IV and infrared detection at 5.72 /zm. 

Gobolos et al. studied reductive amination of acetone with ammonia in a flow system at 169-210°C and 0.8 MPa H2 (H2/NH3 = 0.5) on Raney Ni that had been modified by organic tin compounds with general formula of SnR l (R = Et, Bu, or benzyl) in order to suppress the formation of isopropyl alcohol.16 By introducing tin from tetraalkyl tin, the selectivity to the formation of secondary amine significantly increased at the expense of the primary amine (isopropylamine/diisopropylamine ratio = 68.2/24.1 at 192°C, compared to 83.6/8.6 at 190°C with unmodified catalyst). By modifying the catalyst with SnBzl2Cl2, the lowest selectivity (<1%) for the formation of isopropyl alcohol was obtained at temperatures of 171-202°C. The isopropy-lamine/diisopropylamine ratio was close to the values obtained on the unmodified catalyst (7.3% selectivity to isopropyl alcohol at 190°C). 

Diisopropylmercury yielded isopropylmercuric chloride and isopropyl alcohol as well as acetone. The first two products gave acetone upon further reaction with 03. The following equation appears to describe this system ... 

The zero creep/laser interferometer system was evaluated using A1 foils [0.002 cm thick, 1.905 cm long]. No thickness tolerance was furnished by the manufacturer, however, no discernible variations were observed using a micrometer accurate to 0.1 /im. The foils were washed in acetone and isopropyl alcohol before being mounted in the reactor. The reactor was evacuated before the sample was heated to temperature. The operating vacuum was 7 10 atm at temperature. Typical runs were from 3-4 days in length, and data was collected every 5 seconds. 

A major feature of acetone noted previously is that, along with isopropyl alcohol (IPA), it is considered a universal solvent. This means that acetone and IPA are fiilly miscible with a wide range of compounds within solvent classes such as alkanes, chlorinated alkanes, ketones, and—most inqiortantly— water. Consequently, for those support materials that are used as either NP or RP supports (e.g., cyanqiropyl, aminopropyl, diol), acetone (w IPA) may be used as a conversion solvent For example, to change a cyanopropyl colunm from a NP hexane/ dichloromethane mobile phase to a RP acetonitrile/water system, acetone (or IPA) is equilibrated with the column as an intermediate step. Note that buffers should never be present in any solution during the conversion step. If a buffer is in the mobile phase, then an identical mobile phase without the buffer must be equilibrated with the column prior to the conversion step. 

Gradient solvent systems generally improve the resolution of this chromatographic technique. Outstanding mixtures are isopropyl alcohol in hexane firom 1% to 10% [227], n-heptane/ethyl ether/acetone [228], and acetone in hexane at 8%, 10%, and 12% [229]. 

Cofactor regeneration is potentially possible via electrochemical, chemical, photochemical, and enzymatic methods. The enzymatic methods are of two types those that are enzyme-coupled (using two enzymes) and those that are substrate-coupled. Table 10.3 lists some of the regeneration options. The substrate-coupled approach is particularly attractive [32]. In such systems, it is common to use 2-propanol [isopropyl alcohol (IPA)] as the cosubstrate that leads to acetone as the coproduct. The complication with such a system is that a competitive equilibrium is established... 

A narrow substrate spectrum has been described for tiie yeast alcohol dehydrogenase (YADH) from Saccharomyces cerevisiae, making it a suitable biocatalyst only for molecules like methanol, ethanol, or in some cases acetone. Unfortunately the cofactor NADH is needed, which is regenerated by FDH (Scheme 29.6c). For the asymmetric synthesis of (S)-phenylethylamine with isopropylamine (IPA) as amino donor, acetone was converted to isopropyl alcohol catalyzed by YADH. The effectiveness of this method was compared to the reaction without YADH/FDH. A conversion yield of 99% was achieved with the YADH/FDH system while a conversion yield of 63-89% was obtained without YADH/FDH [69]. 

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