ETHYL ALCOHOL FROM WOOD WASTE. 61 



lulose. The chief constituent of this material soluble in water was a 

 galactan that yielded approximately 10 to 12 per cent of the dry 

 weight of the wood of galactose, and this in turn accounts for the 

 high sugar yields from the larch. If the sugar yield of the larch 

 were recalculated, so that it would be proportionate to the cellulose 

 content (22 per cent being assumed as the yield of sugar from spruce) , 

 there would then be 16.7 per cent of sugar instead of 29.7 per cent, 

 as actually obtained. However, as noted above, about 10 or 12 per 

 cent of galactose was obtained. If this were subtracted from the total 

 sugar yield of 29.7 per cent, there would remain 18 or 19 per cent of 

 sugar comparable to the yield obtained from spruce. Under normal 

 conditions, with a good fermentation and on the assumption that 

 60 to 65 per cent of the total sugar would be fermentable, there would 

 be an alcohol yield of 4.8 to 5.2 per cent; whereas the actual alcohol 

 yield obtained from the larch is 4.997 per cent. This corresponds to 

 about 62 per cent of the total sugars fermentable, which is the average 

 of the above figures chosen for spruce. It appears, therefore, that 

 the yield of fermentable sugars and of alcohol is proportionate to the 

 cellulose content of the wood, as suggested by Korner, 47 but disputed 

 by Gallagher and Pearl, 48 irrespective of other materials that may 

 be present in the wood. 



Western larch butts will be a good raw material for the production 

 of ethyl alcohol if a yeast is found that will ferment the galactose as 

 well as the dextrose within the time limit and under the other con- 

 ditions as prescribed by the Bureau of Internal Revenue. 



In addition to the evidence regarding the source of the fermentable 

 sugars that was presented in the description of the results obtained 

 from the broad-leaved woods, cook No. 98 was made on the leached 

 residue from cook No. 95, which had been given a chlorine and sul- 

 phuric acid treatment. Cooking this residue with 2.5 per cent of 

 sulphuric acid gave only 6.56 per cent of total sugars as compared 

 with the 22 per cent normally obtained from spruce. Through an 

 accident the sugar liquor was lost and no fermentations were made, 

 but the data obtained shows the small yield of sugars obtainable on 

 reinversion, and also indicates that the source of the sugars is the 

 cellulose; for, if the lignin as well as the cellulose were the source, 

 as much sugar would be obtained from the residue as from the 

 original wood, equal weights of material being compared. 



BY-PRODUCTS. 



From longleaf pine and the other pines of the South, about 1 

 gallon of crude turpentine per cord, consisting of the higher-boiling 

 fractions of turpentine and pine oil, can be recovered from the blow- 



« Zeit.fur ang. Chemie., 1908, 2353. 



48 Proc. Eighth International Congress of Appl. Chemistry, vol. 13, p. 147. 



