1,3,-Dioxolane,An Alternative to Formalin as a Standard for Formaldehyde

Four potential primary standards for formaldehyde were evaluated as replacements for the formalin usually used with colorimetric reagents in analyzing textiles for form aldehyde. Of the four—sodium formaldehyde bisulfite, hexamethylenetetramine, tet raoxane, and 1,3,—dioxolane—only 1,3,-dioxolane yielded the stoichiometric amount of formaldehyde under relatively mild conditions of hydrolysis. 1,3,-Dioxolane can be hydrolyzed in 6N HCl for four hours to produce one mole of formaldehyde per mole of 1,3,-dioxolane. Stabilities of standard formaldehyde solutions from 1,3,-diox olane were compared with those from formalin, and there is a discussion of 1,3, dioxolane-based formaldehyde solutions used to prepare calibration curves of several colorimetric reagents for formaldehyde.