SUPPLEMENTARY INFORMATION:

Request To Add Substance to the List

(a) Overview. A petition was filed pursuant to Rev. Proc. 2022-26 (2022-29 I.R.B. 90), as modified by Rev. Proc. 2023-20 (2023-15 I.R.B. 636), requesting that propylene glycol methyl ether acetate be added to the list of taxable substances under section 4672(a) of the Internal Revenue Code (List). The petition requesting the addition of propylene glycol methyl ether acetate to the List is based on weight and contains the information detailed in paragraph (b) of this document. The information is provided for public notice and comment pursuant to section 9 of Rev. Proc. 2022-26. The publication of petition information in this notice of filing is not a determination and does not constitute Treasury Department or IRS confirmation of the accuracy of the information published.

(b) Petition Content.

(1) Substance name: Propylene glycol methyl ether acetate.

(2) Petitioner: The Dow Chemical Company, an importer and exporter of propylene glycol methyl ether acetate.

(3) Proposed classification numbers:

(i) HTSUS number: 2915.39.90.00.

(ii) Schedule B number: 2915.39.9500.

(iii) CAS number: 108-65-6.

(4) Petition filing dates:

(i) Petition filing date for purposes of making a determination: June 13, 2024.

(ii) Petition filing date for purposes of section 11.02 of Rev. Proc. 2022-26, as modified by section 3 of Rev. Proc. 2023-20: July 1, 2022.

(5) Description from petition: According to the petition, propylene glycol methyl ether acetate is an esterification product of propylene glycol methyl ether and acetic acid. Propylene glycol methyl ether acetate, a glycol ether, is a liquid used in a variety of applications including coatings and cleaning.

Propylene glycol methyl ether acetate is made from propylene, chlorine, sodium hydroxide, and methane. Taxable chemicals constitute 93.00 percent by weight of the materials used to produce this substance.

(6) Process identified in petition as predominant method of production of substance: Glycol ethers are predominantly produced by reacting an epoxide (typically ethylene oxide or propylene oxide) with an alcohol; this reaction process is referred to as alkoxylation. Propylene glycol methyl ether acetate is made by esterification of propylene glycol methyl ether and acetic acid. Propylene glycol methyl ether is made via the alkoxylation process (also known as ring opening of an epoxide) using methanol and propylene oxide. Methanol is made from syngas (carbon monoxide and dihydrogen). Carbon monoxide (CO) and dihydrogen (H₂) are made by steam-methane reforming (CH₄ and H₂ O). Propylene oxide is made by hydrochlorination (chlorine (Cl₂), propylene (C₃ H₆), and sodium hydroxide (NaOH)). Acetic acid is made via the carbonylation of methanol with carbon monoxide.

Additional information on the production process:

• The propylene glycol methyl ether alkoxylation reaction (methanol + propylene oxide) is base catalyzed, using a small amount of metal hydroxide to produce methoxide. Once methoxide is made, it is regenerated following conversion to the product in the presence of propylene oxide. Regenerated methoxide in the presence of propylene oxide will perpetually react until all propylene oxide is consumed or the reaction is halted through the use of controls.

○ Since the amount of metal hydroxide used to produce propylene glycol methyl ether is very small, the metal hydroxide has been excluded from the stoichiometric material consumption equation; including the metal hydroxide would lead to a distorted conversion factor.

• After the production of methanol from syngas, methanol is reacted with CO to produce acetic acid. This process is commonly referred to as carbonylation. The reaction is typically catalyzed by either a rhodium or iridium-based catalyst and involves iodomethane as a key intermediate.
• Acetic acid when combined with propylene glycol methyl under specific conditions (temperature, pressure, pH, etc.) produces propylene glycol methyl ether acetate. This reaction is commonly known as esterification (or Fischer Esterification). Esterification typically involves a basic or acid catalytic species and can generate water or an aqueous hydroxide as byproduct depending on the pH. Once the final reaction contents are dehydrated and separated, commercial grade propylene glycol methyl ether acetate is obtained.

(7) Stoichiometric material consumption equation, based on process identified as predominant method of production:

C₃ H₆ (propylene) + Cl₂ (chlorine) + 2 NaOH (sodium hydroxide) + 3 CH₄ (methane) + H₂ O (water) → 2 NaCl (sodium chloride) + 5 H₂ (hydrogen) + C₆ H₁₂ O₃ (propylene glycol methyl ether acetate)

(8) Tax rate calculated by Petitioner, based on Petitioner's conversion factors for taxable chemicals used in production of substance:

(i) Tax rate: $8.85 per ton.

(ii) Conversion factors: 0.32 for propylene, 0.54 for chlorine, 0.61 for sodium hydroxide, and 0.36 for methane.

(9) Public docket number: IRS-2024-0041.

89 FR 71789