ETHYL ALCOHOL FROM WOOD WASTE. 15 



The action of hydrogen peroxide would then necessarily be one of 

 pure hydration, in which the production of hydrocellulose was facili- 

 tated; for, according to Neumann, since the final yield of dextrose is 

 dependent upon the amount of hydrocellulose originally present or 

 upon the speed of its formation, the production of dextrose from hydro- 

 cellulose proceeds at a greater rate than the production of hydrocellu- 

 lose from cellulose. 



From the foregoing it is apparent that, since the publication of 

 Simonsen's work and the obtaining of patents on his process, the 

 production of ethyl alcohol from sawdust has received a very large 

 degree of attention practically all over the world, and large sums have 

 been spent on its technical development. Of the four plants which 

 have been built in this country only two have achieved commercial 

 success, but the failure of the others was due apparently to other 

 things than the process itself. 



OUTLINE OF INVESTIGATIONS. 



The greatest fault common to all of the work that has been done 

 heretofore is that it was aimed chiefly at an increase in the total yield 

 of sugars, whereas, as will be shown later, such an increase does not 

 necessarily mean a proportionate increase in alcohol yield. Most of 

 the fermentation work done was haphazard and not of the same scien- 

 tific character as the chemical work. Without accurate fermenta- 

 tions, and, consequently, without complete data, the interpretation of 

 results led to difficulty, because oftentimes total sugar yields might 

 not vary and yet might give different alcohol yields because of varia- 

 tions in the proportion of fermentable and nonfermentable sugars. 

 Since we have no good quantitative chemical means for separating 

 these two classes of sugars and must depend on fermentation, which is 

 a biological process, carefully standardized fermentation experiments 

 are an absolute necessity. The importance of this point, as will be 

 shown later, can not be too strongly emphasized. Simonsen and 

 others after him have contented themselves with an occasional fer- 

 mentation (usually under conditions that made accurate duplication 

 impossible) to show that some of the sugar obtained was actually 

 fermentable. A careful study of sugar and alcohol relations, espe- 

 cially of the effect of the different variables on that portion of the 

 total sugar that is fermentable, has not, to the knowledge of the 

 writer, been made public heretofore. 



Simonsen, Neumann, and other investigators obtained contra- 

 dictory data because they used as a variable different amounts of 

 an acid solution of constant strength, thereby simultaneously vary- 

 ing both the ratio of water to wood and that of acid to wood. As 

 will be shown in a study of these variables, these ratios are not 

 mutually dependent, and the "acidity" of the solution used for 



