Acetone water separation

A conventional batch still has only one stripping plate, the kettle (Figs 11.2 and 11.3). This is adequate in some cases such as an acetone/water separation (Fig. 11.4) where enriching is difficult and stripping... 

From these equations it can easily be seen that for positive deviation from Raoult s law (Ki > 1) the smallest separation factors and therewith the greatest separation problems occur at the top of the column. To determine the separation factor at the top of the column, one divides by a number larger flian unity y ), while in the bottom of the column one multiplies with a number larger than unity (xf"). While, for example, for the system acetone—water separation factors a little above unity are obtained at the top of the column at atmospheric pressure, separation factors greater than 40 are observed at the bottom of the column (see Chapter 11). In the... 

Fig. 41. The pervaporation separation of acetone—water mixtures achieved with a water-selective poly(vinyl alcohol) (PVA) membrane and with an acetone-selective siUcone mbber membrane. The PVA membrane is best suited to removing small amounts of water from a concentrated acetone solution, whereas the siUcone mbber membrane is best suited to removing small amounts of acetone from a dilute acetone stream (89).

Fig. 7. Extractive distillation column profiles for the acetone—methanol—water separation (40). (a) Liquid composition versus theoretical tray location where...

The chemical propjerties of the contaminants have to be considered when selecting separation techniques. Some of the liquids are absolutely immiscible in water, and if the process stream involves water and the contamination is liquid/liquid, then the separation technique can greatly reduce the volume of contaminated water. For example, if acetone is the contaminant of concern, a simple vap>or stripping technique can be effective in making a separation. In the case of refined oil, which has a solubility limit of approximately 50 ppm, one of the oil/water separation techniques could be effective. Some general guidelines to consider are ... 

The general reaction procedure and apparatus used are exactly as described in Procedure 2. Ammonia (465 ml) is distilled into a 2-liter reaction flask and to this is added 165mlofisopropylalcoholandasolutionof30g(0.195 mole) of 17/ -estradiol 3-methyl ether (mp 118.5-120°) in 180 ml of tetrahydrofuran. The steroid is only partially soluble in the mixture. A 5 g portion of sodium (26 g, 1.13 g-atoms total) is added to the stirred mixture and the solid dissolves in the light blue solution within several min. As additional metal is added, the mixture becomes dark blue and a solid (matted needles) separates. Stirring is inefficient for a few minutes until the mass of crystals breaks down. All of the sodium is consumed after 1 hr and 120 ml of methanol is then added to the mixture with care. The product is isolated as in Procedure 4h 2. After being air-dried, the solid weighs 32.5 g (ca. 100% for a monohydrate). A sample of the material is dried for analysis and analyzed as described in Procedure 2 enol ether, 91% unreduced aromatics, 0.3%. The crude product may be crystallized from acetone-water or preferably from hexane. 

Bisethylenedioxypregn-5-ene. Method A. A mixture of progesterone (10 g), freshly distilled ethylene glycol (80 ml) and benzene (350 ml) is slowly distilled for 15 min to remove traces of water. p-Toluenesulfonic acid monohydrate (0.3 g) is added and the mixture is heated under reflux with stirring for 5 hr with a water separator. Saturated sodium bicarbonate solution is added to the cooled mixture and the benzene layer is separated. The organic layer is washed twice with water, dried and evaporated in vacuo. The residue is crystallized twice from acetone-methanol to give 4.15 g (32%) of bisketal, mp 178-181°. 

B-Norcholesterol Acetate (71). A test tube containing 2 g (4.4 mmoles) of (70) is placed in an oil bath at 150° and the temperature of the bath is slowly raised. At 170°, the liquified mass begins to froth and after 15 min the evolution of CO2 is essentially complete. The melt is allowed to stand at 180° for an additional 15 min. After cooling to room temperature and trituration with 5 ml of acetone, long white plates separate. The crystals are removed by filtration and washed with 70% acetone-water to yield 1.74 g (94%) of (71) mp 77-79°. 

A mixture consisting of 22.7 g potassium o-bromobenzoate, 16.6 g 2,6-dichloro-3-methvlani-line, 12 ml N-ethylmorpholine, 60 ml diethylene glycol dimethyl ether, and 1.0 g anhydrous cupric bromide is heated in a nitrogen atmosphere at 145 C to 155°C for 2 hours. The reaction mixture is diluted with 60 ml diethylene glycol dimethyl ether and acidified with 25 ml concentrated hydrochloric acid. The acidic mixture is diluted with 100 ml of water and the liquid phase decanted from the insoluble oil. The insoluble oil is stirred with methanol and the crystalline N-(2,6-dichloro-3-methylphenyl)anthranilic acid which separates is collected and washed with methanol. The product, after recrystallization from acetone-water mixture melts at 248 C to 250°C. 

M Preparation of isopropyiidene peniciiiamine hydrochioride To the filtrate obtained In step (b) is added at 20°C to 25°C a total of 85 g of hydrogen sulfide. The precipitated HgS is filtered off and the filtrate is concentrated under reduced pressure to a volume of 200 to 500 ml. Following e polish filtration, the product-rich concentrate is mixed with 1.5 liters of isobutyl acetate. The mixture is refluxed at about 40 C under reduced pressure in equipment fitted with a water separation device. When no further water separates, the batch is cooled to 30t and filtered. The reactor is washed with 1 liter of acetone, which Is used also to wash the cake. The cake is further washed with 200 ml of acetone. The acetone washes are added to the isobutyl acetate filtrate and the mixture is refluxed for 20 to 30 minutes. After a holding period of one hour at 5°C, the crystals of isopropyiidene penicillamine hydrochloride are filtered and washed with 200 m of acetone. On drying for twelve hours at 25°C this product, containing 1 mol of water, weighs about 178 g (73%). 

After an initial distillation to split the coproducts phenol and acetone, each is purified in separate distillation and treating trains. An acetone finishing column distills product acetone from an acetone/water/oil mixture. The oil, which is mostly unreacted cumene, is sent to cumene recovery. Acidic impurities, such as acetic acid and phenol, are neutralized hy caustic injection. Figure 10-7 is a simplified flow diagram of an acetone finishing column, and Table 10-1 shows the feed composition to the acetone finishing column. 

Typically lipids, chlorophyll, and phenolic acids can be separated by liquid-liquid partition. Lipids and chlorophyll can be removed from acetone-water extracts by chloroform while phenolic acids have higher affinities for ethyl acetate at a pH close to nentral and water. °°... 

Coman et al. [82] used a new modeling of the chromatographic separation process of some polar (hydroxy benzo[a]pyrene derivatives) and nonpolar (benzo[a]pyrene, dibenz[a,/ ]anthracene, and chrysene) polycyclic aromatic compounds in the form of third-degree functions. For the selection of the optimum composition of the benzene-acetone-water mobile phase used in the separation of eight polycyclic aromatic compounds on RP-TLC layers, some computer programs in the GW-BASIC language were written. 

Figure 4.7 shows the structures of important carotenoids (all-E) lutein, (all-E) zeaxanthin, (all-E) canthaxanthin, (all-E) p-carotene, and (all-E) lycopene. Employing a self-packed C30 capillary column, the carotenoids can be separated with a solvent gradient of acetone water=80 20 (v/v) to 99 1 (v/v) and a flow rate of 5 pL min, as shown in Figure 4.8 (Putzbach et al. 2005). The more polar carotenoids (all-E) lutein, (all-E) zeaxanthin, and (all-E) canthaxanthin elute first followed by the less polar (all-E) p-carotene and the nonpolar (all-E) lycopene. Figure 4.9 shows the stopped-flow II NMR spectra of these five carotenoids. The chromatographic run was stopped when the peak maximum of the compound of interest reached the NMR probe detection volume.

Fig. 2.1. Separations of the pigments of Capsicum annuum on impregnated diatomaceous earth using acetone-water 85 15 (a), 90 10 (b) and 95 5 (c) mixtures as mobile phases. Reprinted with permission from T. Cserhati et al. [14].

Novel pyranoanthocyanins have also been isolated and identified in blackcurrant (Ribes nigrum) seed using HPLC, 2D NMR and ES-MS. Blackcurrant seeds were extracted with acetone-water (70 30, v/v) and the components of the extract were separated in a polyamide column followed by HPLC-DAD. The new pigments were finally separated in an MCI-HP20 column. The chemical structures of anthocyanins 1-2 and the novel pyranoanthocyanins 3-6 with the pyrano[4,3,2-de]-l-bcn/opyrylium core structure are shown in Fig. 2.110. It was stated that the analytical method developed separated well the novel pyranoanthocyanins [245],... 

Silica plates were activated at 120°C for 30 min then cooled in a desiccator. Separations were performed with dichloromethane-methanol mixed in various volume ratios. C18 plates were not pretreated and separation was carried out with mixtures of acetone-water. It was established that both adsortion and RP-TLC can be applied for the separation of tetraphenylporphyrin pigments. Topological indexes may help the better understanding the physicochemical procedures underlying the separation [309],... 

B. 7-Fluoroisatin (3). A 250-mL, three-necked, round-bottomed flask fitted with a condenser and a thermometer is charged with 100 mL of coned sulfuric acid. After heating to 70°C, 30.0 g (0.165 mol) of anilide 2 (Note 9) is added over a period of 1 hr. The resulting deep red solution is heated to 90°C (Note 10) for 60 min (Note 11) and then is cooled to room temperature (20°C) over an ice bath (Note 12). The mixture is then added rapidly to a vigorously stirred mixture of 1.0 L of ice water and 200 mL of ethyl acetate (Note 13). The organic phase is separated and the almost black aqueous phase is extracted twice with 200 mL of ethyl acetate (Note 14). The combined red organic phases are dried with sodium sulfate. The solvent is removed under reduced pressure and the crude product is dried at low pressure, whereupon 12.9 to 15.7 g (47-57%) of an orange powder, mp 186-190°C, is obtained (Note 15). The crude product is sufficiently pure for the next step. Further purification is possible by recrystallization from acetone/water. 

Another complex obtained by template polymerization of dimethylaminoethyl methacrylate in the presence of polyCacrylic acid) was synthesized and analyzed by Abd-Ellatif. The procedure of separation was as follows to the complex dissolved in 10% NaCl solution, 10% NaOH solution was added dropwise and white gel was precipitated. Addition of sodium hydroxide was continued until no more precipitate was separated. The soluble polymer after dialysis was dried and identified as poly(acrylic acid). The insoluble polymer fraction was found to be insoluble in toluene, benzene, tetrahydrofurane, but soluble in acetone/water (2 1 v/v). Elemental analysis and IR spectra lead to the conclusion that this fraction consists of pure poly(dimethyl aminoethyl methacrylate) which was expected as a daughter polymer. 

The transition states for the stepwise (fej, Fig. 2.3) and concerted (fecon) reactions of (4-MeO,X)-3-Y lie at distinct well-separated positions on the More O Ferrall diagram and show different sensitivities to changes in solvent polarity, meta substituents X at the aromatic ring, and the leaving group Y. For example, in 50 50 (v/v) water/trifluoroethanol (4-MeO,H)-3-Cl reacts with azide ion exclusively by a stepwise mechanism through the primary carbocation intermediate (4-MeO,H)-3" with a selectivity for reaction with azide ion and solvent of feaz/ s = 25 However, two-thirds of the azide ion substitution product obtained from the reaction of (4-MeO,H)-3-Cl in the less polar solvent 80 20 acetone/water forms by concerted bimolecular substitution and only one-third forms by trapping of the carbocation intermediate (4-MeO,H)-3 with a selectivity of k z/h = 8 The preferred... 

The nitrosation of 2,5-diphenylpyrrolidine in an ice-cold solution of ethanol and hydrochloric acid with sodium nitrite produced the expected iV-nitroso-2,5-diphenylpyrrolidine. The product could be separated into trans and cis isomers by fractional crystallization using acetone-water mixtures. The ratio of trans to cis isomer was found to be 2.5 1. When the nitrosation was carried out in an acetic acid solution, the ratio of trans to cis isomer remained the same although the yield of the identified products was somewhat lower (71 vs 56 %) [29]. The ratio of the isomers of the starting pyrrolidine was not reported. 

Extraction of soil with hexane acetone (1 1), centrifugation, separation of hexane from acetone/water layer. Extraction of acetone/water phase with chlorofornrdiethyl ether (1 1), solvent exchanged to methanol. Hexane layer contained diazinon, chloroform/diethyl ether fraction contained 2-isopropyl-4-methyl-6-hydroxy-pyrimidine. 

Before removal of DPEHN from this material, it was necessary to dry it. DPEHN dissolves in acetone more readily than PETN, and this is the process used to separate these two nitrates. The crude product is treated with an equal portion (by wt) of acetone. Water is added carefully causing the residual PETN to ppt. The soln separates into two layers ... 

Gude (13) has developed a method for plasticizer separation which resembles the one developed by Burns (8). With an eluent mixture from acetone and water, the spots show even less tail formation Gude argues that acetone makes the PVC swell on the paper hence, the PVC acts as a stationary phase while the acetone-water mixture represents the mobile phase. 

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