January, 1923
INDUSTRIAL A N D ENGINEERING CHEMISTRY
Bakker has successfully applied the inactivation method of reducing sugars by means of alkali to the determination of aucrose in honey. Methods based on the titration of dextrose with iodine are coming into more extended use. More concordant results have been obtained in this way in the analysis of potato-starch sirup than by the use of Fehling’s solution, and the method has also been applied successfully to the analysis of honey. A complete scheme for the analysis of technical invert sugar sirups has been published by Bruhns. A method for the determination of raffinose in beet molasses by the enzyme method has been described by Paine and Reynolds, and the acid method has been revised by Jackson. Schecker states that the most reliable results are obtained by first concentrating the raffinose through repeated precipitation with barium hydroxide, treating with carbon dioxide, and then determination by the Herzfeld method. Viscosity determinations on molasses have been made with the Fischer viscometer, as compared with the Engler instrument, and with a modification of the Arndt viscometer. The dialysis method of the Bureau of Chemistry for determination of colloids, and of gums in particular, has already been mentioned. The hydrogen-ion method of measuring acidity superseded titration in the corn-sirup industry, and the work of Brewster and Raines has paved the way for its introduction in the cane-sirup industry also. It has lately been found that the commonly and officially accepted correction factor in the determination of sulfated ash in cane sirups and molasses is erroneous; the factor is not constant, and is nearer 20 per cent than 10 per cent. There is no need of using the sulfated ash method a t all, as the direct ash method is in most cases just as rapid and convenient and requires 110 empirical correction factor. Adkins and Withrow have shown that, if the sulfated ash method is employed, it should be carried out with dilute instead of concentrated acid. Since the introduction of decolorizing carbons the determination of color in sirups and molasses has become of great importance. The Bureau of Standards has therefore inaugurated a fundamental study of the light transmission of sugar products, and has already worked out a reliable method for color determination. The ordinary color matching instruments have been found to be of no value for the purpose, and some sori, of spectrophotometer must be employed. According to Kauffman, caramel determinations in sirups and molasses are meaningless, and the only method that has any value for comparative purposes is that of Ehrlich. Determination of electrical conductivity by Snell has found an important application in the detection of adulteration of maple sirups. The question of detecting the presence of technical invert sirup in honey has not been definitely settled; a new simple test, using resorcinol and 0-naphthol, has been described by Litterscheid. UTILIZATION The Steffen method of extracting sugar from beet molasses is now universally used in this country. Potvliet has shown, however, that the baryta process (used in Canada) and the strontia process have certain advantages over the Steffen method. The lead saccharate process, experimented with two years ago in Michigan, has evidently been abandoned again. Other, old and new, methods of sugar extraction from molasses are at intervals suggested and patented, but none of them seems to have found favor of late. The profitable disposal of the large quantities of final waste molasses from both cane and beet is quite properly receiving more and more attention. The two main reasons for this activity are the threatened danger of a scarcity of gasoline in the not distant future, and the low price of molasses since the close of the war period. I n certain tropical countries gasoline is already so expensive that the use of
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automobile fuels containing material percentages of alcohol has become an actuality. The alcohol produced from molasses is very simply and easily converted into a practical motor fuel by the admixture of ether which is made from part of the alcohol produced. Pyridine, kerosene oil, and ammonia are the common denaturants. Wherever the new fuel has been carefully manufactured, it has proved a complete success. In the United States conditions have not yet advanced to the point where alcohol motor fuels can successfully compete, but interest in the matter is constantly increasing, as is well demonstrated by the large number of patents, and technical as well as popular articles on the subject. In Europe a number of chemical products are now being manufactured from beet molasses and in this country some work has been done along the same lines. Special fernientation processes, or dry distillation, followed by chemical treatment, are being used or have been proposed for the production of acetone, glycerol, methanol and higher alcohols, fatty acids, ammonia and the methyl amines, methyl chloride, cyanides and other salts of soda and potash, and similar chemicals. Some of these, such as glycerol, butyric acid, nitrogenous compounds, and potash salts can also be made from the distillery slops. The production of potash from the latter was a thriving industry during the war, but has come to a complete standstill again. Whitaker advocates the use of silicon fluoride or hydrofluosilicic acid a s a bactericidal agent in fermentation, and also for precipitating the potash from the molasses itself, instead of making it from the slops. While the manufacture of fuel alcohol from molasses represents the largest potential market of the future, molasses may be profitably utilized in other ways. Arnstein suggests a larger use of molasses for the manufacture of yeast. The foodstuff market absorbs considerable quantities of molasses, whenever it can compete with grain. As a direct fuel, molasses has in most cases been disappointing, but von Stietz has recently designed a special furnace which will burn the molasses properly. Molasses is used as a fertilizer with good results in Mauritius, whereas in other places it has been found of little or no value. Mixtures of molasses with other residual products have lately been tried out in Java, likewise with very poor results. This account would not be complete without mentioning the “Reading List on Molasses,” compiled by C. J. West, comprising a complete bibliography on the subject up to 192Q. Further progress in the sirup industry, particularly cane and sorghum, will probably be in the direction of standardization, and of the manufacture of products that have a n appearance and flavor acceptable to the consumer outside of the restricted area where these sirups now enjoy their greatest popularity. The use of molasses will gradually increase as time goes on and as gasoline becomes scarcer, and it is not beyond the range of possibility that the molasses, now a drug on the market, may yet rival coal tar in value as the source of a variety of important chemicals.
Royal Society Medal Awards Among the awards made by the President and Council of the Royal Society (England) are: The Copley medal to Sir Ernest Rutherford, for his researches in radioactivity and atomic structure; the Rumford medal to Prof. P. Zeeman, for his researches in optics; the Davy medal to Prof. J. F. Thorpe, for his researches in synthetic organic chemistry; the Buchanan medal to Sir David Bruce, for his researches and discoveries in tropical medicine; and the Hughes medal to Dr. E. W. Aston, for his discovery of the isotopes of a large number of the elements by the method of positive rays. The Royal medals have been T.R. Wilson, for his researches on condensaawarded to Mr. tion nuclei and atmospheric electricity; and to Mr. J. Barcroft, for his researches in physiology, and especially for his work on respiration.
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