They may be prepared by the dry distillation of the ammonium salts.
Notwithstanding the inconsistency of his allocation of substances to the different groups (for instance, acetic acid was placed in the vegetable class, while the acetates and the products of their dry distillation, acetone, &c., were placed in the mineral class), this classification came into favour.
The metal is usually obtained from the flue-dust (produced during the first three or four hours working of a zinc distillation) which is collected in the sheet iron cones or adapters of the zinc retorts.
The operation was, however, completely revolutionized in the United States by the introduction of the " cracking process," and by the division of the distillation into two parts, one consisting in the removal of the more volatile constituents of the oil, and the other in the distillation (which is usually conducted in separate stills) of the residues from the first distillation, for the production of lubricating oils and paraffin.
Under such conditions, distillation takes place at higher temperatures than the normal boiling-points of the constituent hydrocarbons of the oil, and a partial cracking results.
The process of distillation of lubricating oils under reduced atmospheric pressure is now in very general use, especially for obtaining the heavier products.
They first invented and named the alembic for the purposes of distillation, analyzed the substances of the three kingdoms of nature, tried the distinction and affinities of alkalis and acids, and converted the poisonous minerals into soft and salutary remedies.
It is decomposed, on dry distillation, into carbon dioxide and pyromellitic acid, C i oH 6 0 8 i when distilled with lime it gives carbon dioxide and benzene.
In the routine examination of crude petroleum it is customary to determine the specific gravity, and the amount of water and earthy matter in suspension; the oil is also frequently subjected to a process of fractional distillation in order to ascertain whether there has been any addition of distilled products or residue.
About six or eight hours after starting the distillation is in full swing, and in twenty-four hours it is completed.
By dry distillation it gives ammonium cyanide.
Sugarmaking, the distillation of rice-spirit, silk-weaving, fishing and the preparation of a fish-sauce (nuoc-mam) made from decayed fish, and the manufacture of salt from sea-water and of lime are carried on in many localities.
Berzelius by the dry distillation of tartaric or racemic acids (Pogg.
By distillation over lime, the methyl group is removed from the pyridine ring, and the resulting a- pyridyl-Nmethylpyrrol gives i-nicotine on reduction.
The exportation in I902 only reached about 45 million gallons (and even that is double the average), while an equally abundant vintage in France and Spain rendered the exportation of the balance of 1907 impossible, and fiscal regulations rendered the distillation of the superfluous amount difficult.
By the action of dilute nitric acid; orthoand para-nitrophenols are obtained, the ortho-compound being separated from the para-compound by distillation in a current of steam.
Its industries include the distillation of oil, tanning, salt-refining, brewing, and the manufacture of earthenware and casks.
By conducting the distillation slowly, so that the temperature within the chamber remains at a sufficiently low degree, it is possible to obtain the whole of the product in the form of "flowers."
If compact ("roll") sulphur is wanted the distillation is made to go on at the quickest admissible rate.
The pyrites is subjected to dry distillation from out of iron or fire-clay tubular retorts at a bright red heat.
It is also produced during the putrefaction of organic substances containing sulphur and is found among the products obtained in the destructive distillation of coal.
Evaporation and subsequent distillation under a high vacuum gives crude glycerin.
Particulars of the shales which yield oil on destructive distillation are given in the article on paraffin.
The first commercial exploitation of importance appears to have been the distillation of the oil at Alfreton in Derbyshire by James Young.
As early as 1804, Humboldt expressed the opinion that petroleum was produced by distillation from deep-seated strata, and Karl Reichenbach in 1834, suggested that it was derived from the action of heat on the turpentine of pine-trees, whilst Brunet, in 1838, adumbrated a similar theory of origin on the ground of certain laboratory experiments.
The earlier supporters of the organic theory held that it was a product of the natural distillation of coal or carbonaceous matter; but though in a few instances volcanic intrusions appear to have converted coal or allied substances into oil, it seems that terrestrial vegetation does not generally give rise to petroleum.
Peckham, but others have held that it is of exclusively animal origin, a view supported by such occurrences as those in the orthoceratities of the Trenton limestone, and by the experiments of C. Engler, who obtained a liquid like crude petroleum by the distillation of menhaden (fish) oil.
The distillation of petroleum, especially of such as was intended for medicinal use, was regularly carried on in the 18th century, and earlier.
Others are deprived of a part of their more volatile constituents by spontaneous evaporation, or by distillation, in vacuo or otherwise, at the lowest possible temperature.
Various arrangements have been proposed and patented for the continuous distillation of petroleum, in which crude oil is supplied to a range of stills as fast as the distillates pass off.
In the United States a horizontal cylindrical still is usually employed in the distillation of the spirit and kerosene, but what is known as the " cheese-box " still has also been largely used.
It is generally understood that the products of fractional distillation, even in the laboratory, are not identical with the hydrocarbons present in the crude oil, but are in part produced by the action of heat upon them.
In an experiment on 3500 grams of paraffin produced from shale (melting point 44'5° C.) they obtained nearly 4 litres of liquid hydrocarbons, which they subjected to fractional distillation, and on examining the fraction distilling below loo° C., they found it to consist mainly of olefines.
This may be brought about by a distillation under pressure, or by allowing the condensed distillate to fall into the highly heated residue in the still.
In this patent, the distillation is described as being conducted in a vessel having a loaded valve or a partially closed stop-cock, through which the confined vapour escapes under any desired pressure.
An objectionable feature of the system of allowing the vapour to escape from the still to the condenser through a loaded valve, viz: the irregularity of the distillation, is thus removed, and the benefits of regular vaporization and condensation under high pressure are obtained.
In the American petroleum refineries it is found that sufficient cracking can be produced by slow distillation in stills of which the upper part is sufficiently cool to allow of the condensation of the vapours of the less volatile hydrocarbons, the condensed liquid thus falling back into the heated body of oil.
The products obtained by the distillation of petroleum are not in a marketable condition, but require chemical treatment to remove acid and other bodies which impart a dark colour as well as an unpleasant odour to the liquid, and in the case of lamp-oils, reduce the power of rising in the wick by capillary attraction.
It is true that by the distillation of many herbs, resins and similar substances, several organic compounds had been prepared, and in a few cases employed as medicines; but the prevailing classification of substances by physical and; superficial properties led to the correlation of organic and inorganic compounds, without any attention being paid to their chemical composition.
The distillation of 1000 lb charge lasts 5-6 hours, requires 500-600 lb coke or 30 gallons reduced oil, and yields about to% metallic zinc and I% blue powder - a mixture of finely-divided metallic zinc and zinc oxide.
PHENANTHRENE, C14H10, a hydrocarbon isomeric with anthracene, with which it occurs in the fraction of the coal tar distillate boiling between 270°-400° C. It may be separated from the anthracene oil by repeated fractional distillation, followed by fractional crystallization from alcohol (anthracene being the less soluble), and finally purified by oxidizing any residual anthracene with potassium bichromate and sulphuric acid (R.
With sodium bisulphite they form the so-called bisulphite compounds Rï¿½CH(OH)ï¿½SO Na, which are readily resolved into their components by distillation with dilute acids, and are frequently used for the preparation of the pure aldehyde.
These aldols generally lose the elements of water readily and pass into unsaturated compounds; aldol itself on distillation at ordinary atmospheric pressure gives crotonaldehyde, CH 3 ï¿½ CH: CH.
By this means a mixture is obtained which by distillation or the action of hydrochloric acid yields trithioaldehyde, (C2H4S)3.
The solution when subjected to distillation behaves very much like a physical solution of the oxide in hydrochloric acid, while a solution of orthostannic acid in hydrochloric acid behaves like a solution of SnC1 4 in water, i.e.
Ether is manufactured by the distillation of 5 parts of 90% alcohol with 9 parts of concentrated sulphuric acid at a temperature of 140°-145° C., a constant stream of alcohol being caused to flow into the mixture during the operation.
The distillation process in former times, especially in England, used to be carried out "per descensum."
In the Belgian process the reduction and distillation are carried out in cylindrical or elliptical retorts of fire-clay, from 3 ft.
In the Silesian process the distillation is conducted in specially constructed muffles of a prismatic shape arched above, which are arranged in two parallel rows within a low-vaulted furnace, similar to the pots in a glass furnace.
Through an orifice in the outlet pipe (which is closed during the distillation by a loose plug) a hot iron rod can be introduced from time to time to clear away any solid zinc that may threaten to obstruct it.
The three isomeric cresols are found in the tar obtained in the destructive distillation of coal, beech-wood and pine.
The crude cresol obtained from tar cannot be separated into its different constituents by fractional distillation, since the boiling points of the three isomers are very close together.
Pictet and P. Crepieux (Comptes rendus, 1903, 137, p. 860) and Pictet and Rotschy (Ber., 1904, 37, p. 1225):, -aminopyridine is converted into its mucate, which by dry distillation gives N-13-pyridylpyrrol.
The residues from petroleum distillation have been shown to contain very dense solids and liquids of high specific gravity, having a large proportion of carbon and possessed of remarkable fluorescent properties.
It may be obtained from storax by distillation with water, and synthetically by heating cinnamic acid with lime, by the action of aluminium chloride on a mixture of vinyl bromide and benzene, by removing the elements of hydrobromic acid from bromethylbenzene by means of alcoholic potash, or, best, by treating (-bromhydrocinnamic acid with soda, when it yields styrolene, carbon dioxide and hydrobromic acid.
Thenard stated that yeast was the cause of fermentation, and held it to be of an animal nature, since it contained nitrogen and yielded ammonia on distillation, nor was it conclusively proved that the yeast cell was the originator of fermentation until the researches of C. Cagniard de la Tour, T.
AlcohoLThe distillation of alcohol is in the hands of three classes of persons.
The alkaloid is obtained from an aqueous extract of tobacco by distillation with slaked lime, the distillate being acidified with oxalic acid, concentrated to a syrup and decomposed by potash.