Correction

Official Monthly Bulletin Interstate Cotton Seed Crushers' Association 88 (CHEMISTS' SECTION) i~ the same turbidity in 90% alcohol as the second "~.T~ when tested ten months later. sa]'~eas~mucb as the samples pass all other requirements for pare castor oil, it did not seem that the oil could have been adulterated but that the incom.plete and slowly .creasing lnSOlUDnl[y was clue to some inner change of ":*'--lecule "l-his is all the more evident when it is t.e--~bered ,,,v - that all oils . other than castor oll have r~r7 l o w acetyl values, so that even a 5% contamination with other oils would have reduced the acetyl value below I4o, whereas both of the samples showed normal values of I48.o and I46.5,.respectively. Further the portmns insoluble in the various alcohols as given above were complete!y soluble in 95% alcohol, thus offering further proot that the insoluble portion was not vegetable oils, but more probably castor oil. At the suggestion of I. F. Laucks, we obtained further proof of this theory. A large quantity of the oil was treated with the alcohol, and the insoluble portion was allowed to settle out. This insoluble portion was freed completely from alcohol and water and a portion tested for its acetyl value. Inasmuch as all other oils have values of less ttian 30 for acetyl value, this insoluble fraction would have a very low acetyl value if the oil had been adulterated. The value as determined, however~ was I36, proving conclusively that the insoluble portion was hydroxylated and therefore castor oil and not any other vegetable oil. This acetylated residue also showed an iodine value of 79.4, which is about what would be expected. We therefore believe that failure to pass the solubility tests, for castor oil especially those specifying alcohol of less than 95% strength should not be considered as proof of adulteration, but rather as an indication that further chemical investigation of such a sample is needed to prove or disprove its purity. Further, while all authors state that the filtration and distillation methods of determiuing the acetic acid liberated from aeetylated oil, give the same results, we have been unable to obtain concordant results by the filtration metho0.. The results are always variable and 10w. Even if the liquid is cooled before filtering, a loss results. This is probably due to the volatilization of the acid. However, distillation, especially if phosphoric acid is used for acidulatifig instead of sulphuric acid, always gives concordant, and consistent results. This method is used for determining the acetic acid in calcium acetates, and we have found it much better for determining the acetyl value than the use of sulphuric acid. If the liquid being distilled is allowed to concentrate to a volume of 50 cc. or less, the sulphuric acid is liable to char the acetylated oil (particularly that material which spatters the sides of the flask above the liquid), and liberates volatile acids which go into the distillate and vitiate the results. By using phosphoric acid, that danger is obviated and we can obtain consistent, results with good checks, whereas by the filtration method we obtained six different values ranging from i25 to i43 on a sample of medicinal castor oil of nown purity, and with a true acetyl value of I48 as etermined by the distillation method. Our method is as follows: Boil gently 20 grs. of filtered dry oil with 2o cc. of acetic auhydride and Io grams of anhydrous sodium acetate in a round-bottomed I5o cc. flask (attached to ~n air-jacketed reflux condenser) for two hours, alowing no material to cake on the sides. Cool somewhat and before breaking: connections rinse down the Condenser with water, adding- about 50 to 8o cc. of water. .Pour the contents of the flask into 5oo cc. of water nta" large beaker and boil for 30 minutes, using glass eacls or a stirring rod reaching the bottom of the beaker to prevent bumping. Siphon off the water and ~ boil the oily layer with fresh water until the wash water is no longer acid to litmus. Separate the acetylated fat from the water, filter and dry in an oven at loo~ Weigh 2-4 grams of the acetylated fat into a 500 cc. Erlenmeyer flask, add 50 cc. of alcoholic potash (40 grs. to the litre) and saponify for one hour. Evaporate off the alcohol and dissolve the soap in water. Fit up the-usual steam distillation apparatus using a twolitre flask for the s.team boiler and allow the steam to escape from the flask for I5 minutes to insure the removal of carbon dioxide from the water. Acidulate the soap solution of the saponified acetylated fat with phosphoric acid using methyl orange as an indicator, conduct the steam into this liquid, and keep both the flasks boiling. Catch the distillate from the Erlenmeyer flask in 40 cc. of quarter normal caustic solution, being careful that the caustic solution seals the end of the delivery tube. After 400 cc. have passed over remove the receiver and titrate back with acid. Continue the distillation, it not being necessary to use caustic in the receiver but being sure that the delivery tube is sealed in with water. Test each TOO cc. of distillate until not more than o.I cc. of quarter normal caustic is necessary to produce a red color with phenophthalein. The total number of ccs. of quarter normal caustic used to titrate the distilled acid multiplied by 2.5 and by 5.6I, and divided by the weight of sample taken, gives the acetyl value. It is better to keep the volume of liquid in the Erlenmeyer flask as small as possible during the distillation to prevent too much splashing, with its consequent carrying-over of the acid solution by entrainment. OCTOBER ADDITIONS TO American Oil Chemists' MEMBERSHIP Society. ACTIVE. A. L. Knisely, II4 Marion St., Seattle, Wash. Leroy H. Habenicht, Kershaw Oil Mill, Kershaw, S.C. W. C. Lord, Falkenburg, Seattle, Wash. P. MeG. Shuey, II5 E. Bay street, Savannah, Ga. D. L. Weatherhead, Wilson-Martin Co., Philadelphia, Pa. Miss Jane E. Mayo, 93 Dodd avenue, Atlanta, Ga. L. E. Walter, Armstrong Packing Co., Dallas, .Texas. Chas. J. Haines, The Electrox Co., Peoria, Illinois. Landon C. Moore, I713 Young St., Dallas, Texas. Alexander W. Beemer, A. E. Staley Mfg. Co., Decatur, Ill. Wm. B. Byers, Southern Cotton Oil Co., Goldsboro, N.C. Carl Neutzel, F. S. Royster Guano Co., Baltimore, Md. J. W. Sehwieger, Southern Cotton Oil Co., Charlotte, N. C. CORPORATION. Barrow-Agee Laboratories, Jackson, Miss. Falkenburg & Co., i i 6 Yesler Way, Seattle, Wash. Hazlehurst Oil Mill and Fertilizer Co., Hazlehurst, Miss. Larrowe Milling Co., Rossford, Ohio. CORRECTION Correction is gladly made of an annoying error in the October issue, where, in the list of Full Certified Referee Chemists, the Fort Worth Laboratories appeared as the "Fort Smith" Laboratories. To all familiar with ,-the names of the chemical laboratories serving the oil mill industry tile mistake would have been self-evident.  (...truncated)