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Dry distillation

CsHsO. Colourless, crystalline solid m.p. 115 C. Prepared by the dry distillation of tartaric acid or by reduction of itaconic or cilra-conic acids. Forms an anhydride when heated to 200"C. [Pg.336]

Dry distillation of sodium laevulinate (I) with phosphorus sulphide gives 2-methylthiophene (II) as the main product ... [Pg.836]

A slightly improved yield is obtained by conducting the dry distillation in a stream of carbon dioxide. [Pg.836]

A solution of 0.10 mol of freshly distilled diethylaminopropyne in 80 ml of dry (distilled from phosphorus pentoxide) acetonitrile was cooled to 5°C and dry carbon dioxide was introduced into the vigorously agitated solution at a rate of about 0.3 1/min. The temperature rose above 20°C within a few minutes, but was kept at about 30°C by occasionally immersing the flask in a bath of ice-water. The introduction of CO2 was continued until the temperature had dropped to 25°C and the typical odour of the yneamine had disappeared completely. The yellow solution was concentrated in a water-pump vacuum. The residue, a sirupy liquid, had the theoretically required weight and consisted of reasonably pure (about 955 ) allenyl-diamide. If desired the product car be distilled (short-path distillation) in a high vacuum. It solidified upon standing at -25 C. [Pg.211]

Theophrastos (272—287 Bc) studied the utilisation of acetic acid to make white lead and verdigris [52503-64-7]. Acetic acid was also weU-known to alchemists of the Renaissance. Andreas Libavius (ad 1540—1600) distinguished the properties of vinegar from those of icelike (glacial) acetic acid obtained by dry distillation of copper acetate or similar heavy metal acetates. Numerous attempts to prepare glacial acetic acid by distillation of vinegar proved to be in vain, however. [Pg.64]

Until World War 1 acetone was manufactured commercially by the dry distillation of calcium acetate from lime and pyroligneous acid (wood distillate) (9). During the war processes for acetic acid from acetylene and by fermentation supplanted the pyroligneous acid (10). In turn these methods were displaced by the process developed for the bacterial fermentation of carbohydrates (cornstarch and molasses) to acetone and alcohols (11). At one time Pubhcker Industries, Commercial Solvents, and National Distillers had combined biofermentation capacity of 22,700 metric tons of acetone per year. Biofermentation became noncompetitive around 1960 because of the economics of scale of the isopropyl alcohol dehydrogenation and cumene hydroperoxide processes. [Pg.94]

Historically, the development of the acrylates proceeded slowly they first received serious attention from Otto Rohm. AcryUc acid (propenoic acid) was first prepared by the air oxidation of acrolein in 1843 (1,2). Methyl and ethyl acrylate were prepared in 1873, but were not observed to polymerize at that time (3). In 1880 poly(methyl acrylate) was reported by G. W. A. Kahlbaum, who noted that on dry distillation up to 320°C the polymer did not depolymerize (4). Rohm observed the remarkable properties of acryUc polymers while preparing for his doctoral dissertation in 1901 however, a quarter of a century elapsed before he was able to translate his observations into commercial reaUty. He obtained a U.S. patent on the sulfur vulcanization of acrylates in 1912 (5). Based on the continuing work in Rohm s laboratory, the first limited production of acrylates began in 1927 by the Rohm and Haas Company in Darmstadt, Germany (6). Use of this class of compounds has grown from that time to a total U.S. consumption in 1989 of approximately 400,000 metric tons. Total worldwide consumption is probably twice that. [Pg.162]

Turpentine Oil. The world s largest-volume essential oil, turpentine [8006-64-2] is produced ia many parts of the world. Various species of piaes and balsamiferous woods are used, and several different methods are appHed to obtain the oils. Types of turpentines include dry-distiUed wood turpentine from dry distillation of the chopped woods and roots of pines steam-distilled wood turpentine which is steam-distilled from pine wood or from solvent extracts of the wood and sulfate turpentine, which is a by-product of the production of sulfate ceUulose. From a perfumery standpoint, steam-distilled wood turpentine is the only important turpentine oil. It is rectified to yield pine oil, yellow or white as well as wood spirits of turpentine. Steam-distilled turpentine oil is a water-white mobile Hquid with a refreshing warm-balsamic odor. American turpentine oil contains 25—35% P-pinene (22) and about 50% a-pinene (44). European and East Indian turpentines are rich in a-pinene (44) withHtfle P-pinene (22), and thus are exceUent raw materials... [Pg.339]

PyrogaHol (1) was first observed by Scheele in 1786 as a product of the dry distillation of gaUic acid [149-91-7] (3,4,5-ttihydroxybenzoic acid). PyrogaHol, which is of widespread occurrence in nature, is incorporated in tannins, anthocyanins, flavones, and alkaloids (1). [Pg.375]

Aniline (hen enamine) [62-53-3] is the simplest of the primary aromatic amines. It was first produced ia 1826 by dry distillation of indigo. In 1840 the same oily hquid was obtained by heating indigo with potash, and it was given the name aniline. The stmcture of aniline was estabUshed in 1843 with the demonstration that it could be obtained by reduction of nitrobenzene. [Pg.228]

The earliest mention of an ammonium carbonate, salt of hartshorn, appears in English manuscripts of the 14th century. As the name implies, the material was obtained by dry distillation of animal waste such as horn, leather, and hooves. Although many salts have been described in the Hterature for the ternary NH —CO2—H2O system, most, except for ammonium bicarbonate [1066-33-7], NH HCO, ammonium carbonate [506-87-6], (NH 2 02, and ammonium carbamate [1111-78-0], NH4CO2NH2, are mixtures (5,6). [Pg.362]

Pyrrohdines also can be obtained by reaction of 1,4-dihydroxyaLkanes with amines in the presence of dehydrating agents at elevated temperatures or by reaction of primary amines with 1,4-dihaloaLkanes. The dry distillation of 1,4-butanediamine dihydrochloride also generates pyrrohdine. Pyrroles can also be catalyticahy hydrogenated to pyrrohdines. [Pg.356]

The pyrolysis or carbonization of hardwoods, eg, beech, birch, or ash, in the manufacture of charcoal yields, in addition to gaseous and lighter Hquid products, a by-product tar in ca 10 wt % yield. Dry distillation of softwoods, eg, pine species, for the production of the so-called DD (destmctively distilled) turpentine yields pine tar as a by-product in about the same amount. Pine tar, also called Stockholm tar or Archangel tar, was at one time imported from the Baltic by European maritime countries for the treatment of cordage and ship hulls it was an important article of commerce from the seventeenth to the nineteenth century. The small amount produced in the late twentieth century is burned as a cmde fuel. Charcoal production from hardwoods, on the other hand, has increased in the 1990s years. [Pg.335]

In 1874, Tiemann and Ha arm ann examined the stmcture of vanillin and reported it to be 3-methoxy-4-hydroxybenzaldehyde. This was not a difficult task because, on treatment with potassium hydroxide, vanillin (1) gave protocatechaic acid [99-50-3] (2), which, in turn, was decarboxylated to catechol [120-80-9] (3) by dry distillation (eq. 1). As both compounds were known at that time, the position of the substituent groups in vanillin was estabHshed. Finally, Reimer synthesized vanillin from guaiacol [90-05-1] and thus proved the identity of its stmcture. In 1894 RhcJ)ne-Poulenc began producing vanillin on an industrial scale. Since then, many other producers have entered into vanillin production, often only to leave it behind. [Pg.396]

Cyclohexanone [108-94-17 is a colorless, mobile Hquid with an odor suggestive of peppermint and acetone. Cyclohexanone is used chiefly as a chemical iatermediate and as a solvent for resias, lacquers, dyes, and iasecticides. Cyclohexanone was first prepared by the dry distillation of calcium pimelate [19455-79-9] OOC(CH2 )5COO Ca , and later by Bouveault by the catalytic dehydrogenation of cyclohexanol. [Pg.425]

Furancarboxylic acid may be prepared by the dry distillation of mucic acid, by the oxidation of furfural with potassium... [Pg.46]

In 1786 William Nieholson wrote A Dictionary of Practical and Theoretical Chemistry. In this work Nicholson mentions that a chemist named Neuman, on distillation of storax (a balsam derived from the tree Liquambar orientalis), had produced a fragrant empyreumatic oil . In 1839 E. Simon carried out some similar experiments, apparently quite independently, and again obtained this essential oil which he ealled styrol. In 1845 M. Glenard and R. Boudault reported on the production of styrol (now known as styrene) by dry distillation of dragons blood, a resin obtained from the fruit of the Malayan rattan palm. [Pg.426]

The principal constituent of storax is cinnamic acid and for laboratory purposes styrene is still most easily obtained in high purity but dry distillation of cinnamic acid and its salts under atmospheric pressure (Figure 16.1). [Pg.426]

Syntheses of Nicotine. Pictet and Cr pieux found that 3-aminopyridine mueate on dry distillation yielded l-(3-pyridyl)pyrrole (I), and this, in accordance with the usual behaviour of such pyrrole derivatives, transfers its pyridyl substituent from the 1- to the 2-position at a red heat giving 2-(3-pyridyl)pyrrole (II), which is nomieotyrine. The potassium derivative of this reacts with methyl iodide to form l-methjd-2-(3-pyridyl)-pyrrole methiodide, which is identical with nieotyrine methiodide (III), and on distillation with lime yields nieotyrine (IV Cl — CH). For a re-investigation of this synthesis see Spath and Kainrath. ... [Pg.40]

Propcrtici>. ] c acid foims microscopic crystals of a charac-teiistlc shape. It is insoluble in water, but dissolves in the presence of many organic substances. On dry distillation it yields ammonia, cyanuiic acid, and urea. [Pg.129]

The dehydrobromination and dequaternization of l,l,3-trimethyl-2-bromomethylpyrrolidinium bromide (158) has been accomplished by dry distillation from potassium acetate (123). Since the product was isolated as the perchlorate salt, no conclusion can be drawn as to whether the original reaction mixture contained the exocyclic enamine (159) or the endocyclic enamine (160) ora mixture of both. [Pg.91]

The body originally known under this name was prepared by the dry distillation of thujylamine or isothujylamine hydrochloride, and is identical with Semmler s tanacetene. ... [Pg.58]

By the dry distillation of trimethyl - thujylammonium hydroxide, Tschugaeff obtained a thujene quite similar to the above, but of considerably higher optical rotation. He therefore considers that two stereoisomers may result from different methods of preparation from thujone. [Pg.58]

Trocken-dekatur, /. dry decatizing. -destlUa-tion, /. dry distillation. [Pg.452]


See other pages where Dry distillation is mentioned: [Pg.163]    [Pg.231]    [Pg.101]    [Pg.172]    [Pg.298]    [Pg.321]    [Pg.322]    [Pg.431]    [Pg.302]    [Pg.82]    [Pg.128]    [Pg.240]    [Pg.246]    [Pg.66]    [Pg.80]    [Pg.339]    [Pg.374]    [Pg.415]    [Pg.630]    [Pg.55]    [Pg.60]    [Pg.82]    [Pg.197]    [Pg.24]    [Pg.185]    [Pg.177]    [Pg.131]   
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See also in sourсe #XX -- [ Pg.964 ]

See also in sourсe #XX -- [ Pg.1882 , Pg.1887 , Pg.1899 , Pg.1912 , Pg.1923 , Pg.2122 , Pg.2200 ]

See also in sourсe #XX -- [ Pg.112 ]

See also in sourсe #XX -- [ Pg.378 ]




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