Compound Celluloses 95 



mum yields of cellulose, and for the reason that it is based 

 upon a well-defined reaction of the lignone group, admitting of 

 perfect control. This group, or rather its R. hexene constituent, 

 reacts with chlorine gas, in presence of water, to form a quinone 

 chloride, without, at the same time, affecting its union with the 

 furfural-yielding complex. On treating the chlorinated fibre 

 with sodium sulphite solution, the lignone chloride is dissolved, 

 and at the same time converted into a brilliant magenta 

 colouring matter. The undissolved residue (75-80 p.ct.) is 

 the cellulose of the fibre. The process is carried out as 

 follows : 



About 5 grms. of the fibre weighed after drying at 100 are 

 (a) boiled for 30 minutes with a dilute solution of sodium hydrate 

 (i p.ct. NaOH), which is kept at constant volume by addition of 

 water. The fibre is well washed on a cloth or wire gauze filter, 

 squeezed to remove excess of water, opened out, placed in a 

 beaker, into which (b) a slow stream of washed chlorine gas 

 is passed. Rapid reaction ensues, and the fibre changes in 

 colour, from brown to a bright golden yellow. To ensure 

 complete conversion of the lignone, it is necessary to leave the 

 fibre for some time (from 30-60 minutes) in the atmosphere 

 of Cl gas. (c] The chlorinated fibre is removed, washed once 

 or twice with water to remove hydrochloric acid, and placed 

 in a 2 p.ct. solution of sodium sulphite ; the solution is gradu- 

 ally raised to the boiling point, a small quantity of caustic soda 

 solution is added (0-2 p.ct. NaOH calculated on the solution), 

 and the boiling continued for 5 minutes, (d) The cellulose 

 is now thrown upon a cloth filter and washed with hot water. 

 It will be found to be almost pure, i.e. white ; but to remove 

 the last residues of the non-cellulose, it may be bleached by 

 immersion in a dilute solution of hypochlorite (0*1 p.ct. 

 NaOCl) for a few minutes, or treated with dilute permanganate 

 solution (o'i p.ct. KMnO 4 ). It is well washed from these 



