40 



BULLETIN" 983, TJ. S. DEPARTMENT OF AGRICULTURE. 



Series Va. — Shortleaf pine. 

 125 per cent of H 2 0; 7.5 atmospheres; 10 minutes. 





Per cent 

 H 2 S0 4 . 



Per cent of 

 total sugars 



Per cent of 

 total sugars 

 . ferment- 

 able. 



Alcohol yields. 



Cook No. 



Per cent of 

 dry wood. 



Gallons 

 absolute 

 per ton. 



48 



2.50 

 4.00 



17.15 

 14.02 



60.27 

 66.59 



5.201 

 4.262 



15.73 

 12.89 



49 





The results of series V and Va for both spruce and shortleaf pine 

 are shown graphically in figures 8 and 9. Figure 8 shows the actual 

 alcohol yield based on the dry weight of the wood, and figure 9 gives 





3KO 



2 5 

 £* 



HE 



zo 



I* 



O vO 



4 













































X 



























i 























































v 

























1 

 i 















































St 



JO 



Rl 



rL 



E> 



f 























{ 



















































Pi 



Nl 



? 

























1 









3 



















































^v 





















I 









- 

















































\ 





















1 





































































s 



pf 



»u 



c 



e ; 





























































) 



i 

































































































( 









2 







































































1 













































































1 













































































. 















































































/ 













































































1 



t 













































































/ 













































































' 





































































ml 



.j 



- 



- 



J' 



























































.o 



-' 





"*" 

















































































































„ . 



« 





































































* 







e 



t 2 3 4 5 6 



YIELD OF ALCOHOL IN % OF DRY WEIGHT OF WOOD 



Fig. 8.— Series V and Va, showing variation in alcohol yield with varying concentrations of sulphuric 

 acid for spruce and shortleaf pine. 



the variations in total sugars and the portion of total sugars that is 

 fermentable. 



Figure 8 shows that the yield of alcohol from spruce increased 

 rapidly with the lower concentrations of acid, but that above 1 per 

 cent of acid the increase was comparatively small, there being little 

 difference between 1 per cent and 3.5 per cent of acid. There was 

 an actual decrease in the alcohol yield from shortleaf pine. This was 

 because of the decrease of total sugars (fig. 9), although the amount 

 of sugars fermentable increased from 60.29 per cent to 66.59 per cent 

 of the total. The shortleaf pine used was a mixture of band sawdust 

 and hogged slabs and edgings containing about 8 per cent of cypress 

 and a considerable quantity of bark. 



Even from spruce a decrease in total sugars is noticeable with 

 acidities above 1.4 percent, but here again the percentage of the total 



