The Manufacture of Ethyl Alcohol from Wood Waste

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1922 Excerpt: ...the data for series II were not at hand. The increase, or rather, the percentage of increase, in fermentable sugars may be explained in part by the fact that there is a selective decomposition; that is, the pentose or reducing substances other than the hexose present are more easily decomposed at the high temperature than is the dextrose. The following table of volatile-acid yields shows that there was greater sugar decomposition, with consequent formation of formic acid, at 9 atmospheres than at 6 atmospheres. A similar increase in formic acid is shown in the curve for series 16 on page 50. As no data were available in the literature on the decomposition of pentoses under the conditions that obtained in these experiments, a number of autoclave cooks were made in which both pure dextrose and pure xylose in sulphuric-acid solutions were used. The solutions were made in such a way that the concentrations of sugar would be comparable to those obtained in the regular runs, and the data from these cooks are given in the two following tables: Solution of 0.8 of a gram of xylose in 100 c. c. of 0.5 per cent sulphlric acid, heated to 112 pounds in 20 minutes. Held at 112 pounds for 15 minutes. In addition to the above two series, one cook was made on an aqueous solution of dextrose instead of a sulphuric-acid solution and with the following results: Aqueous solution of 4 grams of dextrose in 100 c. c. of solution, heated to 112 pounds in 20 minutes. Held at 112 pounds for 15 minutes. Reducing sugar 0.1891 gr. cu.=0.09685X10X4= 3.874 grams of dextrose per 100 c. c. The above data confirm the experimental results obtained in cooks in the series mentioned and are also extremely interesting, as it is found that approximately 50 per cent of xylose was decomposed under t...