Titrimetric Determination of the Chlorohydrin Content

3-Chloro-2-hydroxypropyl-N-alkyl-N,N-dimethylammonium chlorides (chlorohydrins) react stoichiometrically with sodium hydroxide to form the corresponding epoxides.

The excess sodium hydroxide is back-titrated with hydrochloric acid and the end point is determined either potentiometrically or through color change of a cresolphthalein indicator solution.

Titrimetric Determination of the Epoxide Content

2,3-Epoxypropyl-N-alkyl-N,N-dimethylammonium chlorides (epoxides) react in aqueous solutions with hydrochloric acid saturated with magnesium chloride to the corresponding chlorohydrins.

The excess acid is back-titrated with sodium hydroxide and the end point is determined either potentiometrically or through color change of a methyl red indicator solution.

Titrimetric Determination of the QUAB Glycol Content

2,3-Dihydroxypropyl-N-alkyl-N,N-dimethylammonium chlorides (glycols) react stoichiometrically with sodium periodate in neutral solution with cleavage of the CC bond to form aldehydes. Epoxide and chlorohydrin remain unchanged under these conditions.

After adding an excess of sodium arsenite, back-titration is accomplished with sodium periodate. The end point is determined either potentiometrically or by means of a potassium iodide/starch solution as indicator.

Determination of Epichlorohydrin (ECH) and 1,3-Dichloropropanol (DCP) by Gas Chromatography

QUAB reagents may contain epichlorohydrin and 1,3-dichloropropanol at very low concentrations for production-related reasons. The concentration in QUAB is determined by gas chromatography after extraction with diethyl ether.

Epichlorohydrin (ECH) 1,3-Dichloropropanol (DCP)

The calibration is performed by adding ECH/DCP to the QUAB solution being examined.

Note:
Analysis methods for the above ingredients and for other physical and chemical analysis are availabie upon reques