27 CFR § 21.23 - Formula No. 19.

---
identifier: "/us/cfr/t27/s21.23"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "27 CFR § 21.23 - Formula No. 19."
title_number: 27
title_name: "Alcohol, Tobacco Products and Firearms"
section_number: "21.23"
section_name: "Formula No. 19."
chapter_name: "ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY"
subchapter_number: "A"
subchapter_name: "ALCOHOL"
part_number: "21"
part_name: "FORMULAS FOR DENATURED ALCOHOL AND RUM"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "5 U.S.C. 552(a); 26 U.S.C. 5242, 7805."
regulatory_source: "T.D. ATF-133, 48 FR 24673, June 2, 1983, unless otherwise noted."
cfr_part: "21"
---


# 21.23 Formula No. 19.

To every 100 gallons of ethyl alcohol of not less than 160 proof add:

4.0 gallons of either methyl isobutyl ketone, mixed isomers of nitropropane, or methyl *n-* butyl ketone; and

1.0 gallon of either kerosene, deodorized kerosene, gasoline, unleaded gasoline, rubber hydrocarbon solvent, or heptane.