[Code of Federal Regulations] [Title 27, Volume 1] [Revised as of January 1, 2008] From the U.S. Government Printing Office via GPO Access [CITE: 27CFR21.94] [Page 548] TITLE 27--ALCOHOL, TOBACCO PRODUCTS AND FIREARMS CHAPTER I--ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY PART 21_FORMULAS FOR DENATURED ALCOHOL AND RUM--Table of Contents Subpart E_Specifications for Denaturants Sec. 21.94 Acetaldol. (a) Purity. Not less than 90 percent by weight acetaldol as determined by the following method: Dissolve 15 grams of the acetaldol in distilled water and dilute to 1 liter in a volumetric flask. Transfer 5 ml of this solution to a 250 ml glass-stoppered flask containing 25 ml distilled water. Add 25 ml of a freshly prepared 1 percent sodium bisulfite solution. Prepare a blank omitting the acetaldol solution. Place the flasks in a dark place away from excessive heat or cold and allow to stand six hours. Remove flasks and titrate free bisulfite with 0.1 N iodine solution using starch indicator. Percent acetaldol by weight=(ml blank-ml test)x200x0.44/weight of sample Titrations in excess of 100 percent may be obtained if the sample contains appreciable amounts of acetaldehyde. (b) Specific gravity at 20 [deg]C. 1.098 to 1.105.