212 ABSTRACTS OF CHEMICAL PAPERS ORGANIC ANALYSIS. Estimation of Alcohol in the Presence of Phenol. J. Ehrlich. ( J . I d . and Eng. Chem., 1916, 8, 240-241.)-When separating alcohol from phenol by distil- lation from a strongly alkaline solution, the results are by no means exact, owing to the dissociation of the phenate and the appearance of phenol in the alcoholic distillate. This difficulty may be surmounted by converting the phenol into tribromophenol before distilling.A preliminary separation by distillation from alkali is preferable, except when the proportion of phenol is small. The full method is as follows : 50 C.C. of the sample are measured into a 300 C.C. flask containing 30 C.C. of water and made strongly.alkaline with sodium hydroxide to a total volume of about 100 C.C.The liquid is distilled into a 50 C.C. graduated flask containing 1 or 2 C.C. of water, the end of the condenser being extended so that it almost touches the level of liquid in the receiver. When nearly 50 C.C. of distillate have been collected the contents of the receiver are made up to the mark, shaken, and 25 C.C. measured out into another 300 C.C. flask containing 30 C.C.of water. The phenol is precipitated by adding bromine water drop by drop to slight excess, and the liquid immediately decolorised by a few drops of thiosulphate solution. Sufficient strong sodium hydroxide is then added to dissolve the tribromophenol and leave a decided excess of alkali. The full volume should be less than 100 C.C. The liquid is distilled as before, and the contents of the receiver are made up to 50 C.C.The percentage of alcohol calculated from the specific gravity of the distillate x 2 gives the percentage in the original sample. The method is found to be perfectly accurate, the action of the small excess of bromine on the ethyl alcohol being quite inappreciable in a short time at the ordinary temperature. J. F. B. “Formolite” Reaction of Nastukoff as Applied to Oil Residuals and Natural Asphalts.C. Riehardson. ( J . Ind. and Eng. Chem., 1916,8, 319-321.)- Nastukoff (J. SOC. Chem. Ind., 1904, 23, 1082) investigated the results of the reaction between petroleum lubricating oils and formaldehyde and sulphuric acid, and deter- mined the percentage of the resulting product, (‘ formolite,” obtained from oils of various origin.The author has extended the method to the examination of the heavier, more viscous and solid native bitumens employed in the construction of asphalt pave- ments, water-proofing, etc. I t was found upon applying the method to a heavy liquid petroleum residual of sp. gr. 0.962 that the vigorous action of the acid carbonised the material, so that no further action by the formalin was possible. No satisfactory method being found of obviating this and other difficulties in the use of the method, it was decided to collect and weigh the residual oil which was unacted upon.Six bituminous materials representing distinct types of asphalt and oil residuals of nearly the same consistency were investigated, and it was found that the more thoroughly asphaltic a bitumen is the smaller is the amount of saturated hydrocarbons it contains, as evidenced by the residue left by the treatment of the total bitumen, not only with sulphuric acid and paraformaldehyde, but likewise with fuming and even concentrated sulphuric acid. The use of formaldehyde was there-ORGANIC ANALYSIS 213 soludle Bitu- men (Pure Basis).fore discontinued, since the materials examined may be as well differentiated by the use of sulphuric acid as by the ‘‘ formolite ” reaction. 1 Ordinary Filming H2S04 and H2S04.H2S04. (HCOH),. - Nauh tha- I Per Cent. Saturated Hydrocarbons by- Texas residual ... ... California residua1 ... Mexican ,, ... Trinidad ,, ... Bermudez refined asphalt Trinidad ,, 9 , .-. ... ... ... ... ...64.3 65.0 72.2 73.1 71.9 64.9 44-5 40.1 37.5 32-7 28.3 23 *7 37.5 38.2 31.3 28.4 22.6 22.3 ~ 35.8 33.0 25.2 24.0 21.1 22.7 H. F. E. H. Determination of the Specific Gravity of Fixed Oils in the Tropics. C. H. Wright, ( J . SOC. Chem. Ind., 1916, 35, 457-458.)-1n countries where the dew point of the air is above 15.P C. it is difficult to determine the sp. gr. of a liquid at this temperature owing to the condensation of moisture on the bottle or Sprengel tube.If the oil is cooled to 15.5” C. and its sp. gr. determined by the Westphal balance a similar difficulty arises: since moisture condenses on the surface of the oil and on the platinum wire attached to the plumet. The following procedure is therefore recommended. The weight of water held by a sp. gr. bottle is determined at the temperature of the air; the weight of oil held by the bottle is also determined at the same temperature.The weight of water held by the bottle at 1505~ C. is where Wt= weight in air of water held by the bottle at to C. ; dt= weight in air of 1 C.C. of water at to C. (see Sutton’s “Volumetric Analysis,” tenth edition, 1911, p. 26) ; d15.5 =weight in air of 1 C.C.of water at 15.5” c. (0.99804 grm.) ; and a= the coefficient of cubical expansion of glass (0-0000258). The weight of oil held by the bottle a t to C. is now divided by the weight of water held by the same bottle at 15.5” C. to obtain the sp. gr. of the oil at to C. (&),,and from this value the sp. gr. of the oil at 15.5’ C. (815.5) is found from the equation, 1 - 0.0007 x 15.5 - 0.98915 - st 1 - 0.0007t’ 815.5 = St x 1 - 0.0007t in which the modulus of expansion of fixed oils is taken to be 0-0007 (see ANALYST, 1907, 32, 295).w. P. s. Method of Estimating the Amount of Seasoning of Teak Wood. A. C, Sircar. (J. SOC. Chem. Ind., 1916, 35, 452-454.)-The method proposed depends on the fact that teak wood sawdust yields on steam distillation either214 ABSTRACTS OF CHEMICAL PAPERS a crystalline or an oily substance, or a mixture of the two, according as the wood is seasoned, unseasoned, or partially seasoned. The oily substance may be separated from the crystalline substance by means of methyl alcohol, in which solvent the crystalline substance is only slightly soluble, and the quantity of oily substance obtained on evaporating the methyl alcohol solution affords an indication of the degree of seasoning which the wood has undergone.One hundred grms. of the freshly-made sawdust from the sample of wood should be steam distilled until 1 litre of distillate has been collected; the distillate is then extracted with ether, the ethereal solution evaporated at ordinary temperature, and the residue weighed.The residue is now treated with 1.5 C.C. of methyl alcohol, which at once dissolves the oily substance, the solution is filtered through a very small filter, the filter washed with a drop or two of methyl alcohol, the alcoholic filtrate is evaporated at ordinary temperature, and the oily residue weighed. The crystalline substance does not come over completely with the first litre of distillate, the succeeding fractions of 1 litre each up to the tenth containing small and practically equal quantities of the substance ; even in the case of fresh teak wood, the greater part of the oily substance appears in the first litre of distillate, and none is found in the fourth or fifth litre.When 1 litre of distillate is collected, as prescribed, the weight of the residue soluble in methyl alcohol never exceeds 0.0188 grm.in the case of properlyseasoned woods (e.g., woods over 5 years old), and is less than 40 per cent. of the total ether soluble residue obtained from the distillate. Unseasoned woods yield from 0.2 to 0.8 grm. of residue soluble in methyl alcohol, and the residue has a, distinct oily appearance; it constitutes from 70 to 80 per cent.of the total ether soluble residue. w. P. s. Estimation of Soluble Nitrocellulose in Guncotton. H. C. Mallinson. (J. .Ind. and Eizg. Chem., 1916, 8, 401-402.)-According to the British Government specification method the guncotton is treated with ether-alcohol, shaken every fifteen minutes for about six hours, and an aliquot portion of the extract evaporated and dried.The method tends to give high results owing to occlusion of the solvent which is not completely driven off in the drying. I t is preferable, therefore, to precipitate the soluble nitrocellulose by pouring the solution into water and to collect and dry the precipitate. The shaking of the guncotton with ether-alcohol is performed far more conveniently by mechanical means. According to the rapid method proposed, 5 grrns.of the sample (or less if the degree of solubility is high) are treated with 200 C.C. of ether-alcohol in a graduated 200 C.C. cylinder. Agitation is effected by attaching the cylinder to a block of wood clamped on a shaft revolving at from 5 to 11 revolutions per minute. Complete extraction of the soluble matter is thus attained within one hour, as compared with six hours by hand.After the residue has settled, 50 C.C. of the clear extract are transferred to a dish, and about 500 C.C. of water at 75" to 80" C. are poured slowly down the inside of the dish, the complete evaporation of the solvent being effected by immersing the floating cake of precipitate below the surface of the hot water by means of a rod, The mode of collecting the precipitate depends on its character.If it takes the form of a coherent mass, with only a few detached particles which can be picked out withORGANIC ANALYSIS 215 the forceps, it is placed between filter papers, after moistening with alcohol and pressed. Drying can then be completed in twenty minutes in the oven at 72' C. If the precipitate takes the form of disconnected flakes it is collected on a pair of counterpoised filter papers, the contents of the dish being washed down with alcohol.The collected matter on the filter is pressed between the folds of a towel, dried in the oven, and weighed with one filter paper in each pan. If preferred, the precipi- tate may be collected in a Gooch crucible, so manipulated that the precipitate itself makes its own filter-bed.The results are always slightly lower than by the evaporation method, and, therefore, more accurate; the error of the latter, due to enclosed solvent, increases with the quantity of soluble matter. J. F. B. Direct Estimation of Rubber in a Compound. R. W. Belfit. (J. Ind. and Eng. Chem., 1916, 8, 326-327.)-The method described gives excellent results with high-grade mixings, but is not applicable to mixings containing lampblack, shoddy, ground leather, starch, egg albumen, or other organic compounds insoluble in acetone, water, or dilute hydrochloric acid.It depends on extraction of the sample first with acetone and then with dilute hydrochloric acid, and the combustion of the residue, the resulting carbon dioxide being absorbed by potash and weighed.The sample (2 grms.) should pass a 20-mesh sieve, but should not be much finer, I t is extracted with boiling acetone for 5 hours, dried in a, current of carbon dioxide a t 100" C., and weighed. About half of the extracted sample is weighed into a 250 C.C. flask and boiled for thirty minutes with 150 C.C. of dilute (1 : 5) hydrochloric acid. The acid liquid is decanted through an alundum crucible with the aid of suction, and the residue washed three times by decantation and ten times on the filter with water at 60" C.The residue is then dried at 100" C. for three hours in a current of carbon dioxide. After weighing, a portion of about 0.3 grm. is submitted to combustion analysis. No copper spiral is used, but oxides of nitrogen are absorbed together with water by a small quantity of concentrated sulphuric acid containing chromic acid in solution.Any acid gases other than carbon dioxide are absorbed by zinc dust in an appropriate apparatus and the carbon dioxide by potash in the usual manner. From the weight of carbon dioxide found that of the corresponding amount of C1,Hl, is calculated. When fine Para gum is submitted to analysis in this way, about 96% of (ClOKl,Jn is indicated.I n the analysis of mixings, therefore, the apparent weight of (C,oH16)a in the portion taken for combustion is divided by 0.96 to obtain the corre- sponding weight of rubber. The percentage of rubber in the original sample is then calculated by reference to the percentage loss on treatment with acetone, the fraction of the original sample taken for the acid extraction and the fraction of the fully extracted sample taken for combustion.G. C. J. Estimation of Barium Carbonate and Barium Sulphate in Vulcanised Rubber Goods. J. B. Tuttle. (J. Ind. and Eng. Chenz., 1916, 8, 324-326.)- Many specifications now permit the use of barium sulphate without having the sulphur which it contains count as part of the specified total sulphur.The estima- tion of total barium presents no difficulty (India Rubber World, 1914, 51, 128 ; U.S. Bureau of Standards Circular, No. 38,3rd ed., 1915,68), and, if no compound of barium216 ABSTRACTS OF CHEMICAL PAPERS other than the sulphate is present in the mixing, the necessary correction is readily made. Barium carbonate, however, may be present, and it is therefore necessary to. have a means of estimating this.Since lead sulphate may be simultaneously present, the separation of barium carbonate from barium sulphate cannot be carried out by solution of the carbonate in acids, for lead sulphate will pass into solution and subse- quently react with the barium with precipitation of barium sulphate.Solution of the lead sulphate in ammonium acetate is also untrustworthy. The following method has proved satisfactory : The rubber (1 grm.) is ignited in an atmosphere of carbon dioxide, the residue finely ground, treated with 5 to 10 grms. ammonium carbonate, 15 to 20 C.C. of strong ammonia, and about 50 C.C. of water, and boiled for fifteen to thirty minutes. This treatment converts lead sulphate into carbonate, but has an almost negligible effect on barium sulphate.The soluble sulphates are removed by filtration and the residue on the filter is washed back into the original beaker and boiled with about 100 C.C. of 10 per cent. acetic acid. The solution is filtered from the barium sulphate, using the same filter as before. In the filtrate, lead is precipi- tated as sulphide, which is filtered off.Finally, in the filtrate from the lead, the barium originally present as carbonate is precipitated by adding 10 C.C. of 10 per cent. sulphuric acid to the hot solution, allowing to stand in a warm place over- night, filtering, igniting, and weighing as sulphate. G. C . J. Estimation of Tartaric Acid. B. G. Hartmann, J. R. Eoff, and M.J. Ingle. (J. Ind. and Eng. Chem., 1916, 8, 422-425.)-The Halenke and Moslinger method for precipitating acid potassium tartrate (Zeitsch. anaZ. Chem., 1895, 34, 279) has been taken as the basis of the present work, but, as originally devised, it has been found unreliable when employed on wines and fruit juices containing much free tartaric: acid. This is attributed to the reversibility of the main reaction under the influence of the hydrochloric acid liberated, and the difficulty may be surmounted by adding to the wine sufficient alkali to neutralise its acidity, and then the molecular equiva- lent of pure tartaric acid to convert the neutral tartrates into acid tartrates.In applying the method to wines, 100 C.C. are treated with sufficient sodium hydroxide to neutralise, according to a predetermined titration, and pura powdered tartaric acid equivalent to the alkali used is then added.Subsequently 2 C.C. of glacial acetic acid and 15 grms. of potassium chloride axe added, and, when the salt is dissolved, 15 C.C. of 95 per cent. alcohol, The liquid must be stirred until precipitation has started, and is then left overnight at a temperature not exceeding 15' C. The precipitate is collected in a Gooch crucible with pulp filter-bed, using gentle suction, and washed three times with 7 C.C.of a solution composed of 100 C.C. of water, 15 grms. of potassium chloride, and 20 C.C. of 95 per cent. alcohol. The precipitate and filter are transferred to the original beaker with 50 C.C. of hot water, the liquid is brought to the boil and immediately titrated with Fa sodium hydroxide in presence of phenolphthalein.The burette reading is increased by 1.5 C.C. to correct for solubility, then multiplied by 0,015, and the quantity of added tartaric acid sub- tracted, If the liquid during precipitation be stirred mechanically, accurate results can be obtained in thirty minutes. If desired, Rochelle salt mag be added instead of tartaric acid, provided its content of tartaric acid be previously determined. I nINORGANIC ANALYSIS 217 the case of grape juice, 50 C.C. of the filtered juice are neutralised as described and diluted to 100 C.C. The procedure is then the same as for wines, except that 20 C.C. instead of 15 C.C. of alcohol are used. I n the case of syrups, removal of the sugar by fermentation or separation of the acid as lead salt is advisable. In the case of liquids containing tartaric acid, free phosphoric acid, and alcohol, inferior results are obtained, and all the methods become less reliable the older the solutions. This is due to esterification, with the formation of ethyl tartrates. I t is found, however, that complete saponification of the esters is produced by adding 5 C.C. of $ sodium hydroxide to 50 C.C. of the solution in excess of the quantity required to neutralise, bringing to the boil, and allowing to stand overnight. The addition of the calculated amount of tartaric acid, dilution of the solution to 100 c.c., and the continuation of the method as applied to wines yield quantitative results for the total tartaric acid. J. F. B.