Naphthalene

“ The phenols of naphthalene are called naphthols—they bear the same relationship to naphthalene that carbolic acid bears to benzene. Owing to the structure of the naphthalene molecule there are two isomeric naphthols, whereas there is only one phenol. ”

“ C. Graebe in 1866 (Ann. 149, p. 20) established the symmetry of the naphthalene nucleus, and showed that whichever half of the molecule be oxidized the same phthalic acid results. Therefore formula (2) , being unsymmetrical, is impossible. The third formula is based on Dewar’s benzene formula, which we have seen to be incorrect. Formula (4) is symmetrical and based on Kekulé’s formula: it is in full accord with the syntheses and decompositions of the naphthalene nucleus and the number of isomers found. In 1882 Claus suggested a combination of his own and Dewar’s benzene formulae. ”

“ Numerous di- and tri-sulphonic acids are known.
α-Naphthoquinone, C10H6O2, resembles benzoquinone, and is formed by the oxidation of many α-derivatives of naphthalene with chromic acid. It crystallizes in yellow needles which melt at 125° C. It sublimes readily, is volatile in steam and reduces to the corresponding dihydroxynapthalene. β-Naphthoquinone is formed by oxidizing 2-amino-α-naphthol (from β-napthol-orange by reduction) with ferric chloride. It crystallizes in red needles which melt at 115° C; it has no smell and is non-volatile (cf. phenanthrenequinone) . ”

“ The solubility of naphthalene by various oils has led some engineers to put in naphthalene washers, in which gas is brought into contact with a heavy tar oil or certain fractions distilled from it, the latter being previously mixed with some volatile hydrocarbon to replace in the gas those illuminating vapours which the oil dissolves out; and by fractional distillation of the washing oil the naphthalene and volatile hydrocarbons are afterwards recovered. ”

“ Restricting ourselves to compounds resulting from the fusion of benzene rings, we have first to consider naphthalene, C10H8, which consists of two benzene rings having a pair of carbon atoms in common. The next members are the isomers anthracene and phenanthrene, C14H10, formed from three benzene nuclei. Here we shall only discuss the structure of these compounds in the light of the modern benzene theories; reference should be made 58 to the articles Naphthalene, Anthracene and Phenanthrene for syntheses, decompositions, &c. ”

“ The main difficulty which the condenser ought to overcome and upon which its efficiency should depend is the removal of naphthalene: this compound, which is present in the gas, condenses on cooling to a solid which crystallizes out in the form of white flakes, and the trouble caused by pipe stoppages in the works as well as in the district supplied is very considerable. The higher the heat of carbonization the more naphthalene appears to be produced, and gas managers of to-day find the removal of naphthalene from the gas a difficult problem to solve. ”

“ With increased production of coal tar and intensive efforts to recover the maximum of naphthalene there has been a larger output of naphthalene in recent years, but increased consumption has created a scarcity in Germany as in all other important producing countries. As a result, greatly reduced quantities are available for export, a situation that is in marked contrast to earlier periods when superabundant production created a marketing problem. The manufacture of phthalic anhydride for alkyd resins is requiring increased quantities of naphthalene. ”

“ He found that by acting on naphthalene—the moth-ball stuff—with chlorine he got a series of useful products called "halowaxes." The lower chlorinated products are oils, which may be used for impregnating paper or soft wood, making it non-inflammable and impregnable to water. If four atoms of chlorine enter the naphthalene molecule the product is a hard wax that rings like a metal.
Condensite is anhydrous and infusible, and like its rivals finds its chief employment in the insulation parts of electrical apparatus. The records of the Edison phonograph are made of it. ”

“ In recent years about one-half of domestic requirements of crude naphthalene have been imported (see table 46) from Europe, principally Germany and the United Kingdom. Increased demand for the same purposes, in these countries, has so reduced the quantities available for export as to create a serious shortage in the United States. Germany placed an embargo on exports late in 1935 and continued it until late in 1937.
Table 46.—Crude naphthalene: United States production, imports, and apparent consumption in specified years
1 From table 33. ”

“ The pyridine ring condenses with the benzene ring to form quinoline and isoquinoline; acridine and phenanthridine are dibenzo-pyridines; naphthalene gives rise to α- and β-naphthoquinolines and the anthrapyridines; anthracene gives anthraquinoline; while two pyridine nuclei connected by an intermediate benzene nucleus give the phenanthrolines. Naphthyridines and naphthinolines result from the condensation of two pryridine and two quinoline nuclei respectively; and quino-quinolines are unsymmetrical naphthyridine nuclei condensed with a benzene nucleus. ”

“ Exports are not shown separately; it is doubtful if any naphthalene is exported. Demand in the United States has exceeded domestic production.
Competitive conditions.
The commercial development and widespread application of surface coatings and finishes made from alkyd resins, in which phthalic anhydride and glycerin are the principal components, has resulted in a world-wide shortage of naphthalene, which is a raw material used in making phthalic anhydride. ”

“ Most of the oil which passes as the “creosote-oil fraction” is sold in the crude state for the purpose of pickling timber. It is at the ordinary temperature a semi-solid mixture of about 20% crystallized hydrocarbons (chiefly naphthalene) , and 80% of a dark brown, nauseous smelling oil, of 1.04 spec. grav., and boiling between 200° and 300° C. The liquid portion contains phenols, bases, and a great number of hydrocarbons. Sometimes it is redistilled, when most of the naphthalene passes over in the first fraction, between 180° and 230° C., and crystallizes out in a nearly pure state. ”

“ The weight of the lid by compressing the felt is sufficient to render the box air-tight. Six or eight glass vessels containing crude benzene are placed at the bottom of the chest and of the coffin itself. It need scarcely be added that the box must not be opened near a fire or light, as the vapour forms an explosive mixture with air; it is in fact advisable to have no light or fire in the room.
Insects can also be killed by naphthalene vapour, but as [161] naphthalene is insufficiently volatile at ordinary temperatures, the method above described is more convenient [173] . ”

“ During recent years an immense number of ringed or cyclic compounds have been discovered, which exhibit individual characters more closely resembling benzene, naphthalene, &c. than purely aliphatic substances, inasmuch as in general they contain double linkages, yet withstand oxidation, and behave as nuclei, forming derivatives in much the same way as benzene. ”

“ For the further treatment to make di-nitro-naphthalene, 18 parts of nitro-naphthalene are placed in an earthenware pan, together with 39 parts of sulphuric acid of 66° B., then 15 parts of nitric acid of 40° B. are added, in small quantities at a time, stirring the mixture continually. This adding of nitric acid is controlled by the fuming, which should be kept down as much as possible. ”

“ Interactions between analytes may reduce breakthrough volumes and affect desorption efficiencies. Naphthalene, originally validated in S292 [4] , failed to meet acceptable desorption efficiency recovery and storage stability criteria at the levels evaluated in this study. However, the application of this method to naphthalene levels at or near the REL/PEL continues to meet acceptable recovery criteria. Styrene failed to meet acceptable recovery criteria at the two lowest levels evaluated in this study (highest level to meet the criteria was 181 μg/sample) . ”

“ In practice, for instance, 10 kilos of naphthalene is heated with the same weight of concentrated sulphuric acid (66° Bé) , when the mixture is converted into [Greek: b] -naphthalenesulphonic acid by heating for several hours at 150°-160° C; the sulphonation completed, the sulphonic acid is cooled to about 85° C., and 4 kilos of formaldehyde (30 per cent, by weight) slowly added; finally, the product is stirred at the temperature mentioned till all formaldehyde has combined. ”

“ One of the best coloring matters was known as Martius's yellow, naphthol yellow, naphthalene yellow, Manchester yellow, saffron yellow, or golden yellow, and is chemically the same as the dinitroalpha-naphthol prepared from the naphthalene that crystallizes in gas mains, which is an important constituent in the making of lyddite. It is slightly explosive when heated, is injurious when it comes in contact with an abrasion of the skin, and has been shown by physiological experiments to be a highly improper substance to mix with food. ”

“ It is manufactured by oxidizing naphthalene tetrachloride (prepared from naphthalene, potassium, chlorate and hydrochloric acid) with nitric acid, or, better, by oxidizing the hydrocarbon with fuming sulphuric acid, using mercury or mercuric sulphate as a catalyst (German pat. 91, 202) . It also results on the oxidation of diderivatives of benzene. It forms white crystals, melting at 213° with decomposition into water and phthalic an hydride; the latter forms long white needles, melting at 128° and boiling at 284°. Heated with an excess of lime it gives benzene ”

“ Moreover, these secondary products cannot be successfully reduced, by further heating, to simpler hydrocarbons of any high illuminating value, and such bodies as naphthalene and anthracene have so great a stability that, when once formed, they resist any efforts again to decompose them by heat, short of the temperature which breaks them up into methane, carbon and hydrogen. ”

“ The crude product includes far more than half its weight of impurities—phenanthrene, paraffin, naphthalene, &c. To remove these as far as possible, the crude anthracene is ground up and treated with petroleum spirit (boiling at 70° to 100°C.) or coal tar naphtha (120° to 190°) , in which real anthracene is relatively insoluble. ”

“ The artificial colouring-matters have in this last case once again threatened a natural product, and with greater success than the indigo synthesis, for the introduction of the azo-scarlets has caused a marked decline in the cochineal culture.
In addition to the azo-colours, there are certain other products which claim naphthalene as a raw material. In 1879 it was found that one of the sulpho-acids of beta-naphthol when treated with nitrous acid readily gave a nitroso-sulpho-acid. ”

“ Naphthalene also begins to show in quantity in the tar as soon as the yield of gas reaches 10,000 cub. ft. per ton of coal carbonized.
In spite of these variations, however, the products in their main characteristics will remain the same. ”

“ Naphthalene and the usual malodorous powders are not only very disagreeable, but quite useless. Any chemical that is strong enough to destroy the life in a moth egg would also be sufficiently potent to injure the fur itself. ”

“ It is produced in small quantity in the distillation of amber, on passing the vapour of phenyl-naphthyl-methane through a red-hot tube, on heating indene, or by passing the mixed vapours of coumarone and naphthalene through a red-hot tube. ”

“ This placed the production of quinone on a manufacturing basis, so that when a demand for hydroquinone sprung up, the wants of the photographer were met by the technologist. Eikonogen is another organic reducing agent, discovered by the writer in 1880, and introduced as a developer by Dr. Andresen in 1889. It is an amido-derivative of a sulpho-acid of beta-naphthol, so that naphthalene is the generating hydrocarbon of this substance. ”

“ Ltd. at Faversham. It is composed of tri-nitro-toluol 11 parts, ammonium nitrate 93 parts, and moisture 1 part. This explosive must be used only when contained in a case of an alloy of lead, tin, zinc, and antimony thoroughly waterproof; it must be used only with a detonator or electric detonator of not less strength than that known as No. 6.
~Nitro-Naphthalene.~—Nitro-naphthalene is formed by the action of nitric acid on naphthalene (C_{10}H_{8}) . Its formula is C_{10}H_{7}NO_{2}, and it forms yellow needles, melting at 61° C. ”

“ But our table shows us more; it indicates to us what the steps are from each raw material to each colouring matter, as well as showing us each colouring matter. We see here that our benzene yields us an equal weight of aniline, and the toluene (9/10 lb.) about 3/4 lb. of toluidine, the mixture giving, on oxidation, between 1⁄2 and 3/4 lb of Magenta. From carbolic acid are obtained both Aurin and picric acid, and here is the actual quantity of Aurin obtainable (1-1/4 lb.) . From naphthalene, either naphthylamine (a body like aniline) or naphthol (resembling phenol) may be prepared. ”

“ It is always better to use a larger rather than a smaller quantity of these crystals Great care should be exercised to keep tightly closed the trunks or chests of clothing with which the naphthalene is stored. ”