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Acetone from plants

The US. Pharmacopeia (USP XXII) or National Formula (NFXVII) (20) also provide a similar description however, the peroxide value is not defined (Table 9). These specifications are also given in the Handbook of Pharmaceutical Excipients (HPE), pubhshed jointiy by the American Pharmaceutical Association and The Pharmaceutical Society of Great Britain (21), which defines lecithins both from plants and eggs. The Merck Index (22) specifies a slightiy lower acid value. The Japanese Monograph (ISCI-II) (23) specifies a slightiy lower acetone-insoluble matter and a lower heavy-metal content. [Pg.103]

Production of a-methylstyrene (AMS) from cumene by dehydrogenation was practiced commercially by Dow until 1977. It is now produced as a by-product in the production of phenol and acetone from cumene. Cumene is manufactured by alkylation of benzene with propylene. In the phenol—acetone process, cumene is oxidized in the Hquid phase thermally to cumene hydroperoxide. The hydroperoxide is spHt into phenol and acetone by a cleavage reaction catalyzed by sulfur dioxide. Up to 2% of the cumene is converted to a-methylstyrene. Phenol and acetone are large-volume chemicals and the supply of the by-product a-methylstyrene is weU in excess of its demand. Producers are forced to hydrogenate it back to cumene for recycle to the phenol—acetone plant. Estimated plant capacities of the U.S. producers of a-methylstyrene are Hsted in Table 13 (80). [Pg.491]

Residues of flumioxazin are extracted from plant matrices with aqueous acetone. The extracted residues are partitioned into dichloromethane. The dichloromethane is removed through rotary evaporation. Partitioning between hexane-acetonitrile followed by Florisil column chromatography purifles the plant extract. Residues of flumioxazin are quantitated by gas chromatography GC. [Pg.503]

Pyriminobac-methyl in plant samples (rice grains and rice straw) and soil is recovered by refluxing with aqueous acetone. After removing acetone from the extract, pyriminobac-methyl in the aqueous solution is transferred into n-hexane. The n-hexane layer is dried and evaporated under reduced pressure. The residue from soil... [Pg.551]

Hymexazol residues are extracted from plant materials with acetone and partitioned into aqueous sodium hydrogen carbonate solution. The aqueous solution is washed with dichloromethane and diethyl ether. After acidification of the... [Pg.1211]

Isoxathion is extracted from plant materials with aqueous acetone. The extracts are concentrated and partitioned with n-hexane after addition of sodium chloride. The n-hexane phase is collected and concentrated after dehydration. The extract is partitioned with n-hexane and acetonitrile. The acetonitrile phase is collected, concentrated, and subjected to Horisil column chromatography. Isoxathion is eluted with diethyl ether-n-hexane after washing the column with the solvent. Isoxathion in the eluate is concentrated and dissolved in acetone and injected into a gas chromatograph for quantitative determination. [Pg.1327]

In a sensitive and specific colorimetric method 1,1,1-trichloro-2,2-bis(p-methoxyphenyl)-ethane is extracted from plant or animal tissue, using benzene or petroleum ether as the solvent. The solvent is evaporated at room temperature by a current of air and the residue dehydroha log ena ted with 2% alcoholic potassium hydroxide. By petroleum ether extraction the resulting 1,1-dichloro-2,2-bis(p-methoxyphenyl)-ethylene is removed from the reaction mixture. After the solvent is removed by air evaporation the dehydroha log ena ted methoxychlor is isolated from the nonsaponifiable portion of the fats and waxes by dissolving the residue in hot acetone, chilling, and filtering. After the acetone is removed by air evaporation, the residue is treated with 85% sulfuric acid. This produces a red solution with an absorption maximum at 555 m/z, the intensity of which can be read on a colorimeter and is a function of the methoxychlor concentration. Beer s law is obeyed over the range of 1 to 50 micrograms. [Pg.260]

In the absence of other ignition source), fires in plant to recover acetone from air with active carbon are due to the bulk surface effect of oxidative heating when air flow is too low to cool effectively. [Pg.436]

In addition to these larger VOCs, there are biogenic sources of a wide variety of small alcohols, aldehydes, ketones, and acids. For example, emissions of methanol and acetone have been reported from plant leaves, grass, and clover (e.g., MacDonald and Fall, 1993 Nemecek-Marshall et al., 1995 Fall and Benson, 1996 Kirstine et al., 1998). Table 6.25 shows some of the compounds measured in grass and clover emissions (Kirstine et al., 1998). Clearly, a wide variety of oxygen-containing species are emitted from this one source alone. Direct emissions of formaldehyde, ac-etaldehye, and formic and acetic acids have been observed from oaks and pines (Kesselmeier et al., 1997). [Pg.230]

Weizmann discovered a process to produce butyl alcohol and acetone from the bacterium Clostridium acetobutylicum in 1914. With England s urgent demand for acetone, Winston Churchill (1874-1965) enlisted Weizmann to develop the Weizmann process for acetone production on an industrial scale. Large industrial plants were established in Canada, India, and the United States to provide the allies with acetone for munitions. Weizmann, who is considered the father of industrial fermentation, obtained significant status from his war contributions and used this to further his political mission of establishing a Jewish homeland. Weizmann was a leader of the Zionist movement and campaigned aggressively until the nation of Israel was established in 1948. He was the first president of Israel. [Pg.5]

The most common solvents used for the extraction of polyphenolics from plant material are methanol, ethanol, acetone, ethyl acetate, and their aqueous solvents. Aqueous methanol is a popular choice of solvent because it is efficient, has a high boiling point, and is eco-... [Pg.1245]

Carbon, Air. Recovering acetone from the air, in plants, with active carbon resulted in fires due to the air flow being too low to cool effectively.5... [Pg.7]

Example 2. Consider Figure 2, which is a fragment taken from the acetone distillation process described earlier in this chapter. Here we are looking at the feed of acetone from the storage tank to the distillation column. The designer has now been able to design this part of the plant in detail. [Pg.326]

Ipatieff was, first of all, a brilliant and able teacher who preferred the title of Professor to any other. His research activity of a purely scientific nature brought with it unusual industrial success, and many plants, operating all over the world, are based on catalytic reactions discovered by him. Among the most important of his contributions are the introduction of high-pressure techniques in chemistry and chemical industry, destructive hydrogenation, the production of acetone from propyl alcohol, and the production of high-octane aviation fuel by the reactions of polymerization, alkylation, and isomerization. He was the first to demonstrate the specificity of catalysts and the use of mixed catalysts and promotors. [Pg.498]

ABA is extracted from plants and other sources usually by methanol. Methanolysis of glucosyl ester of ABA sometimes occurs to give its methyl ester as an artifact,570 and acetone is used for extraction to avoid the methanolysis. The methyl ester of ABA is not always an artifact. Its occurrence in stigma of tobacco has been confirmed by extraction using acetone.571 Ethyl acetate is used to extract ABA and its natural catabolites,... [Pg.54]

Capacity of Plant for Producing Acetone from Isopropanol 841... [Pg.818]

You are designing a plant for the production of acetone from isopropanol. Acetone is produced according to the following reaction ... [Pg.842]

Provitamin D2. Ergosterol is isolated exclusively from plant sources. The commercial product is ca 90—100% pure and often contains up to 5 wt % of 5,6-dihydroergosterol. Usually, the isolation of provitamin D2 from natural sources iavolves the isolation of the total sterol content, followed by the separation of the provitamin from the other sterols. The isolation of the sterol fraction iavolves extraction of the total fat component, its saponification, and then reextraction of the unsaponifiable portion with an ether. The sterols are ia the unsaponiftable portion. Another method is the saponification of the total material, followed by isolation of the nonsap onifiable fraction. Separation of the sterols from the unsap onifiable fraction is done by crystallization from a suitable solvent, eg, acetone or alcohol. Ethylene dichloride, alone or mixed with methanol, has been used commercially for recrystallization. In the case of yeasts, it is particularly difficult to remove the ergosterol by simple extraction, thereby obtainiag only ca 25% recovery. Industrially, therefore, the ergosterol is obtaiaed by preliminary digestion with hot alkaUes or with amiaes (28—33). Variations of the isolation procedure have been developed. Eor example, after saponification, the fatty acids may be precipitated as calcium salts, which tend to absorb the sterols. The latter are then recovered from the dried precipitate by solvent extraction. [Pg.127]


See other pages where Acetone from plants is mentioned: [Pg.48]    [Pg.48]    [Pg.87]    [Pg.103]    [Pg.431]    [Pg.91]    [Pg.319]    [Pg.35]    [Pg.141]    [Pg.31]    [Pg.598]    [Pg.702]    [Pg.775]    [Pg.157]    [Pg.164]    [Pg.9]    [Pg.116]    [Pg.357]    [Pg.63]    [Pg.135]    [Pg.164]    [Pg.27]    [Pg.119]    [Pg.26]    [Pg.321]    [Pg.206]    [Pg.519]   
See also in sourсe #XX -- [ Pg.613 , Pg.614 ]




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Acetone from

From plants

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