27 CFR 21.123: Pyronate.

Pyronate is a product of the destructive distillation of hardwood meeting the following requirements:

(a) Acidity (as acetic acid). Not more than 0.1 percent by weight, determined as follows:

Add 5.0 mL sample to 100 mL distilled water in an Erlenmeyer flask and titrate with 0.1 N NaOH to a bromthymol blue endpoint.

(b) Color. The color shall be no darker than the color produced by 2.0 grams of potassium dichromate in 1 liter of water. The comparision shall be made in 4-ounce oil sample bottles viewed crosswise.

(c) Distillation range. When 100 mL are distilled not more than 5 mL shall distill below 70 °C., not less than 50 mL below 160 °C., and not less than 90 mL below 205 °C.

Note.

Any material submitted as pyronate must agree in color, odor, taste and denaturing value with a standard sample furnished by the Alcohol and Tobacco Tax and Trade Bureau to chemists authorized to examine samples of denaturants.