Abstract: Disclosed is a method of determining whether a solvent contains a tautomeric cyclic 1,2-dione. It is first determined whether the pH of the solvent is acidic (<5), basic (>9), or neutral (5 to 9). If the pH is neutral, an acid or a base is added to make the pH acidic or basic, respectively. The UV absorbance at a first wavelength between about 230 nm and about 270 nm and at a second wavelength between about 280 and about 320 nm is determined. If the pH is acid, it is changed to basic and, if it is basic, it is changed to acidic. The UV absorbance at the first and second wavelengths is again determined. The presence of a tautomeric cyclic 1,2-dione is indicated if the absorbance at the first wavelength was greater when the solvent was acidic and the absorbance at the second wavelength was greater when the solvent was basic. The concentration of the tautomeric cyclic 1,2-dione can be determined by multiplying the change in absorbance by a constant.

Abstract: Disclosed is a method of making a glycol ether acetate. Acetic acid is reacted with a glycol ether at a molar ratio of about 1.1 to about 2, in a mixture with a catalyst and an azeotropic agent which can be either butyl acetate or dibutyl ether. The mixture is heated to a temperature and pressure sufficient to vaporize an azeotrope of water and the azeotropic agent. In another embodiment of the invention, a glycol ether acetate is made by preparing a reaction mixture of acetic acid and a glycol ether in a molar ratio of about 1.1 to about 1.2, about 5 to about 25 wt % n-butanol, an additional amount of acetic acid stoichiometric with the amount of n-butanol, and a catalyst. The reaction mixture is heated to form a glycol ether acetate, water, and butyl acetate. The azeotrope, excess acetic acid, butyl acetate, and glycol ether are successively removed by distillation.

Abstract: Disclosed is a method of reducing the decomposition of liquid acetates and increasing their storage life. A soluble amine having a pH in water between 9 and 12 is added to the acetate. Also disclosed is a composition of about 1 to about 50 ppm of the amine in the acetate.