[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: 27CFR21.106] [Page 551] 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. 21.106 Diethyl phthalate. (a) Refractive index at 25 [deg]C. 1.497 to 1.502. (b) Color. Colorless. (c) Odor. Practically odorless. (d) Solubility. Soluble in 20 parts of 60 percent alcohol. (e) Specific gravity at 25 [deg]/25 [deg]C. 1.115 to 1.118. (f) Ester content (as diethyl phthalate). Not less than 99 percent by weight. Note. The sample taken for ester determination should be approximately 0.8 gram. The number of ml of 0.5 N potassium hydroxide used in saponification multiplied by 0.05555 indicates the number of grams of ester in the sample taken for assay. [T.D. ATF-133, 48 FR 24673, June 2, 1983. Redesignated by T.D. ATF-442, 66 FR 12854, Mar. 1, 2001]