ETHYL ALCOHOL FROM WOOD WASTE. 7 



Willstatter and Feichmeister 7 with fuming hydrochloric acid on 

 cotton and wood has confirmed these results; but in all those experi- 

 ments the amounts of acid required have been so large that the initial 

 and recovery costs for acid have prevented commercial development. 

 Whether the source of the fermentable sugars is the cellulose or 

 the lignin of the wood has long been a subject for debate and has 

 also been the occasion of considerable investigation; but the fact 

 remains that a wood cellulose like soda or sulphite pulp has been 

 found to produce about twice as much fermentable sugar and alcohol 

 as the same amount of the original wood, the yields being in propor- 

 tion to the cellulose content. 



HISTORY OF THE PROCESSES. 



The first recorded attempts to produce sugars and alcohol from 

 vegetable fiber were those of Braconnot 8 in 1819. From that time 

 until the publication of Simonsen's 9 paper in 1898 little work of 

 value was done. 10 Simonsen's review of the problem is well worth 

 quoting here, because it tersely describes the situation at that time: 



The literature of this problem is imperfect and faulty to a high degree. It contains 

 many inaccurate and impossible statements and contradictions. There is no record 

 of any systematic investigation as to the effect of a variation of the different factors, 

 such as amount of water, pressure, amount of acid, and time in high-pressure inver- 

 sions. Parallel and comparative experiments on cellulose and wood are also lacking, 

 so no information on the relation of the incrusting substances to the inversion processes 

 is at hand. That these investigations may have been made and their results kept 

 secret is not impossible, since factories have been established. Such researches 

 could hardly have dealt with high-pressure inversion, which has only been carried 

 out practically on a large scale for the last 20 years. Yet the manufacture of spirit 

 from cellulose material by means of inversion under such unfavorable conditions as 

 that over 100 per cent of sulphuric acid was required for the dry wood and the corre- 

 sponding quantity of calcium carbonate or lime (and taking into account the high 

 price of the material at that time and the length of time required for the process) 

 seems to point to the fact that the inversion of wood will be the method of the future 

 if only a satisfactory process can be found. 



Simonsen carried out a long and painstaking research on the 

 subject, in which he investigated both cellulose (sulphite cellulose) 

 and sawdust in a systematic way. As an inverting agent he used 

 sulphuric acid, and from his results concluded that the best condi- 

 tions for the inversion of sawdust were as follows : 



Time of inversion 15 minutes. 



Acidity 0.5 per cent H 2 S0 4 . 



Proportion of wood to liquid 1 to 4. 



Pressure about 9 atmospheres. 



^ Berichte, 1913, 2401. 

 aKoerner, Zeit. Ang. Chem., 1908, 2353. 

 8 Gilbert's Annalen der Physik, 1819, 63, 348. 

 s Zeit. liir ang. Chemie, 1898, 195, 962, 1007. 



10 The references to the original literature from 1819 to 1898 will be found in the bibliography at the end 

 of this bulletin. 



