the mixture is more strongly heated.

The reaction products are distilled under ordinary pressure until
the temperature of the liquid has reached 140'0 (thermometer bulb
immersed in the liquid). The residual products are distilled
under diminished pressure, and the following fractions obtained.
(1) Up to 115'0/11 mm.; (2) 115-117'0/ 11 mm.; (3) 117-170'0/11 mm.
(1) is mostly aqueous hydrochloric acid; (2) is the monochlorohydrin;
and (3) is glycerol. The second portion is redistilled and the portion
boiling at 115-118'0/11 mm. or 133-136'0/20 mm. is collected.
The yield is 190-205 g., 53-57 per cent of the theoretical amount.


3. Other Methods of Preparation

The following methods of preparing monochlorohydrin are described
in the literature: action on glycerol of gaseous hydrogen
chloride;[1] action of gaseous hydrogen chloride on glycerol
mixed with an equal volume of acetic acid;[2] action of aqueous
hydrochloric acid on glycerol[3] alone or with an organic acid
(1-2 per cent), such as acetic, as a catalyst;[4] gaseous hydrogen
chloride with an organic acid, as acetic, as a catalyst;[1b] gaseous
hydrogen chloride with the ester of an organic or inorganic acid
as a catalyst;[2b] the action of sulfur monochloride on glycerol.[3b]

[1] Ann. 88, 311 (1853); Ann. chim. phys. (3) 41, 297
(1834); V. R. P. 254,709; 269,657; Frdl. 11, 31 (1912).

[2] Ann. chim. phys. (3) 60, 18 (1860).