Rev. Rul. 60-286

Section 212.57 of the Regulations relating to Formulas for Denatured Alcohol and Rum prescribes the denaturants to be used in specially denatured alcohol Formula No. 40. Laboratory tests have shown that another product, designated `Bitrex (THS-839),' is also suitable as a denaturant for this formula. Allordingly, this denaturant is authorized under authority of section 212.65 of the regulations, as an alternate denaturant for Formula No. 40, as follows:

To every 100 gallons of alcohol add 1/4 av. ounce of denaturing grade Bitrex (THS-839) and 1/8 gallon on tert -butyl alcohol.

The specifications for denaturing grade Bitrex (THS-839) are as follows:

Bitrex (THS-839) is a synthetic quaternary ammonium compound; Benzydiethyl (2:6-xylylcarbamoyl) ammonium benzoate, having an intensely bitter taste.

Color -White (crystalline powder) Melting Point -158-161%A1C.

Solubility at 20%A1C. -One gram is soluble in 1.5 ml. water and in 1.5 ml. ethyl alcohol. Solutions are clear and colorless and reasonably free of extraneous matter.

Assay -Not less than 99 percent C 28 H 34 O 3 N 2 . Dissolve about 0.5 gm. Bitrex (THS-839) accurately weighed in 60ml. glacial acetic acid, cool; add 15 ml. of a 5 percent w/v solution of mecuric acetate in glacial acetic acid, and titrate with N/10 perchloric acid in glacial acetic acid using 0.2 ml. of a 0.5 percent w/v solution of crystal violet in glacial acetic acid as indicator (or methylrosaniline chloride T.S.). Repeat the titration omitting the samples. The difference between the two readings will represent the volume of perchloric acid required by the sample. Each ml. of N/10 perchloric acid is equivalent to 0.04465 gm. C 28 H 34 O 3 N 2 .

Identification Tests -(a) Dissolve about 0.15 gm. sample in 10 ml. water, and add 15 ml. of 0.66 percent w/v trinitrophenol in water; the melting point of the precipitate after washing with water and drying is about 175%A1C.

(b) Dissolve about 0.1 gm. sample in 10 ml. water and add 20 ml. dilute sulfuric acid and 30 ml. 1 percent w/v ammonium reineckate in water; the melting point of the precipitate after washing with water and drying, is about 170%A1C.

Bitterness -An alcoholic or aqueous solution of Bitrex (THS-839) shall be distinctly bitter at 1 to 250.000 dilution.

Optical Assay -When 25 ml. of an aqueous solution containing 1 part in 10,000 of Bitrex (0.1 gm/L) is made acid with 1 ml. of HC 1 , and extracted 3 times with a total of 100 ml. of diethyl ether, the resulting ether extract shall have an absorbance in a 1 cm. cell of not less than 0.400 at a wavelength of 228 millimicrons.