The invention discloses a method for preparing a
thiamine hydrochloride crystal product.
Thiamine mononitrate is dispersed into a
solvent, and
thiamine mononitrate turbid liquid with the concentration of 0.05 g / ml to 0.2 g / ml is obtained, and heated to 50 DEG C to 70 DEG.
Chlorosulfonic acid is dropwise added to concentrated
hydrochloric acid to generate
hydrogen chloride gas, and the gas is introduced into to concentrated
sulfuric acid to be dried, and is introduced into the
thiamine mononitrate turbid liquid under stirring action. After introduction of the
hydrogen chloride gas is completed, heat preservation is carried out for 15 min to 30 min, then the temperature is reduced to 10 DEG C, the
cooling rate ranges from 0.1 DEG C / min to 0.5 DEG C / min, filtering, washing and
drying are carried out, and then
thiamine hydrochloride crystals are prepared. The crystals are rhabdolith, the
angle of repose ranges from 31 DEG C to 36.4 DEG C, and the
bulk density ranges from 0.50 g / ml to 0.608 g / ml. The
thiamine hydrochloride crystal product is good in liquidity. According to the method, the process that
thiamine hydrochloride methyl
alcohol solvent compounds are formed firstly, then
drying is carried out to remove methyl
alcohol is avoided, and therefore environmental
pollution is reduced, and cost and
solvent residues are reduced. The method can be suitable for large-scale production.