yielded furfural 2.3 p.ct.
D. Cotton and nitric acid at 100° (four hours).—A more highly oxidised product resulted, viz. 3 C6H10O5.C6H8O6: yielded furfural 3.2 p.ct.
By-products of oxidation.—The liquors from B were found to contain saccharic acid: the acid from C and B contained a dibasic acid which appeared to be tartaric acid.
The isolation of (1) isosaccharinic and (2) dioxybutyric acid from the products of digestion of the oxycelluloses with lime-milk at 100° was effected by the separation of their respective calcium salts, (1) by direct crystallisation, (2) by precipitation alcohol after separation of the former.
CELLULOSES, HYDRO- AND OXYCELLULOSES, AND CELLULOSE ESTERS.
L. Vignon (Bull. Soc. Chim., 1901 [3], 25, 130).
(a) Oxycelluloses from cotton, hemp, flax, and ramie.—The comparative oxidation of these celluloses, by treatment with HClO3 at 100°, gave remarkably uniform results, as shown by the following numbers, showing extreme variations: yields, 68-70 p.ct.; hydrazine reaction, N fixed 1.58-1.69; fixation of basic colouring matters (relative numbers), saffranine, 100-200, methylene blue, 100-106. The only points of difference noted were (1) hemp is somewhat more resistant to the acid oxidation; (2) the cotton oxycellulose shows a somewhat higher (25 p.ct.) cupric reduction.
(b) 'Saccharification' of cellulose, cellulose hydrates, and hydrocellulose.—The products were digested with dilute hydrochloric acid six hours at 100°, and the cupric reduction of the soluble products determined and calculated to dextrose.
| 100 grms. of | gave reducing products equal to Dextrose |
| Purified cotton | 3.29 |
| " Hydrocellulose | 9.70 |
| Cotton mercerised (NaOH 30° B.) | 4.39 |
| Cotton mercerised (NaOH 40° B.) | 3.51 |
| Cellulose reprecipitated from cuprammonium | 4.39 |
| Oxycellulose | 14.70 |
| Starch | 98.6 |
These numbers show that cellulose may be hydrated both by mercerisation and solution, without affecting the constitutional relationships of the CO groups. The results also differentiate the cellulose series from starch in regard to hydrolysis.