142 Cellulose 



disintegrated fibre-elements or ultimate fibres. The yield from 

 normal specimens is about 60 p.ct. Only the more resistant 

 cellulose a survives the treatment, the cellulose /3, together with 

 the lignone complex, being converted into soluble derivatives. 



Extreme action of alkaline hydrates. With the caustic 

 alkalis in concentrated solution and at temperatures exceed- 

 ing 120, much more drastic decompositions take place, 

 the entire molecule being attacked. For complete resolution 

 into simple molecules (oxalic, acetic, and carbonic acids) the 

 proportion of alkaline hydrate to lignocellulose requires to be 

 2-3 to i, and the temperature raised to 250, and maintained 

 at that point for some hours. Thus, on heating jute for 8 

 hours at 250 with 3 times its weight of KOH, the yields of 

 the main products were : acetic acid, 37-0 p.ct. ; oxalic acid, 

 53-3 p.ct. of the lignocellulose (J. Soc. Chem. Ind. n, 966). 

 The action is an oxidising action, in the sense that hydrogen 

 is expelled ; gaseous carbon compounds (CO, CH 4 ) are formed 

 in relatively small quantities. 



DECOMPOSITIONS BY OXIDANTS. (i) Acid. Certain of 

 these are more important as contributing to the elucidation of 

 constitutional points. 



(a) Chromic add. The direction of attack of this oxidant 

 depends upon the auxiliary conditions, chiefly upon the 

 presence of hydrolysing acids. With the CrO 3 alone, the 

 interaction with the lignocellulose is at first one of simple 

 combination ; afterwards the CrO 3 fixed is gradually deoxidised. 

 Under these circumstances the lignocellulose suffers a very 

 slight loss of weight. In presence of acids, however, the fibre- 

 substance loses in weight, and the insoluble residue is affected 

 more or less. The following results may be cited in illus- 

 tration : 



CrO z alone. (i) 4*5 grms. jute, containing 0*7 p.ct. ash 

 constituents, digested 18 hours in i p.ct. solution CrO 3 



