ASTM D7423-23 PDF

Full title and description

Standard Test Method for Determination of Oxygenates in C2, C3, C4, and C5 Hydrocarbon Matrices by Gas Chromatography and Flame Ionization Detection (Designation: ASTM D7423‑23). This method specifies a multidimensional gas chromatography procedure with flame ionization detection (GC‑FID) for the quantitative determination of low‑level organic oxygenates (alcohols, ethers, aldehydes, ketones and related species) in light hydrocarbon matrices (C2–C5 streams, LPG, light naphtha) whose final boiling point does not exceed about 200 °C.

Abstract

ASTM D7423‑23 defines a GC‑FID based analytical procedure for identifying and quantifying trace oxygenates in light hydrocarbon matrices. The method covers method scope, required instrumentation (multidimensional GC with valves and appropriate columns), calibration and quality control, typical analyte retention times, and a linear working concentration range intended for trace determinations. It is intended for use where oxygenates at mg/kg (ppm) levels must be measured to control downstream processes or product quality.

General information

• Status: Published / Active.
• Publication date: 2023 (standard designation D7423‑23; commonly listed with publication dates in early 2023).
• Publisher: ASTM International (American Society for Testing and Materials).
• ICS / categories: 71.080.01 (Organic chemicals in general) — petroleum / organic chemicals analytical methods.
• Edition / version: D7423‑23 (2023 edition).
• Number of pages: ~9 pages (concise test method, typical published length ~8–9 pages).

Scope

This test method applies to the quantitative determination of organic oxygenates in C2, C3, C4 and C5 hydrocarbon matrices by multidimensional GC with flame ionization detection. It is applicable to matrices having a final boiling point not greater than about 200 °C, and to oxygenate concentrations within the method’s validated linear working range (reported at about 0.50 mg/kg to 100 mg/kg). Identification is by reference standards and retention order; the method includes recommended instrumentation, column arrangements (multidimensional/heart‑cutting), valve timing and calibration procedures to separate trace polar oxygenates from the hydrocarbon matrix. The method does not address safety procedures in detail — users must apply appropriate LPG / hydrocarbon safety practices.

Key topics and requirements

• Analyte classes: alcohols, ethers, aldehydes, ketones and related oxygenates commonly found as trace impurities in C2–C5 streams.
• Instrumentation: multidimensional gas chromatograph configured for heart‑cutting or Deans‑switch style separations, capillary columns selected for volatile oxygenate separation, sampling valves for gas and liquid introduction, and flame ionization detector (FID).
• Calibration and range: gravimetric or prepared standards with specified internal standards; linear working range approximately 0.50 mg/kg to 100 mg/kg for most oxygenates.
• Matrix limitations: suitable for light hydrocarbons with final boiling point ≤ ~200 °C; not intended for heavy hydrocarbon fractions or fuels outside the stated range without validation.
• Typical reported retention times / analyte list: method includes a table of oxygenates and typical retention times (e.g., dimethyl ether, diethyl ether, acetaldehyde, MTBE, ETBE, methanol, ethanol, propanols, butanols, acetone, MEK, TAME, etc.).
• Quality control: method procedural blanks, calibration checks, retention time verification with ID mixes, and limits of quantitation/precision statements derived from interlaboratory study data where provided.

Typical use and users

Typical users include analytical and quality laboratories at refineries, petrochemical facilities, gas processing and LPG plants, catalyst manufacturers and polymer plants (where oxygenates impair catalyst performance), environmental testing labs evaluating light hydrocarbon streams, and instrument vendors who provide ASTM‑compliant GC solutions. The method is used for product acceptance, process control, contamination troubleshooting, and providing trace‑level specifications for feedstocks and intermediates. Suppliers of calibration standards and GC analyzer configurations commonly reference this method when offering turnkey solutions.

Related standards

Standards commonly referenced alongside or for related analyses include ASTM D7754 (trace oxygenates in automotive spark‑ignition fuels by multidimensional GC, D7754‑23), ASTM D4815 (determination of MTBE, ETBE, TAME, DIPE and C1–C4 alcohols in gasoline), and the earlier edition ASTM D7423‑17 (superseded by D7423‑23). These provide complementary procedures and calibration materials for different fuel types and concentration ranges.

Keywords

oxygenates; alcohols; ethers; GC‑FID; multidimensional gas chromatography; C2 C3 C4 C5 hydrocarbons; LPG; naphtha; retention time; calibration; trace analysis; ASTM D7423‑23.

FAQ

Q: What is this standard?

A: ASTM D7423‑23 is a Standard Test Method that defines a multidimensional gas chromatography with flame ionization detection procedure for the quantitative determination of trace organic oxygenates in light hydrocarbon matrices (C2–C5).

Q: What does it cover?

A: It covers applicable matrices (final boiling point ≲200 °C), instrument configuration (multidimensional GC, valves, capillary columns and FID), calibration and QC practices, typical analytes and retention times, and a validated linear working range for trace quantitation (approximately 0.50 mg/kg to 100 mg/kg). Users must follow local safety procedures for handling flammable hydrocarbon samples.

Q: Who typically uses it?

A: QA/QC and process laboratories in refineries, petrochemical plants, gas processing/LPG operations, catalyst and polymer manufacturers, environmental labs and vendors of GC analyzer systems and calibration standards.

Q: Is it current or superseded?

A: The designation D7423‑23 indicates the 2023 edition; it supersedes the prior edition (D7423‑17). At the time of publication this version is the active method; users should confirm any later revisions or ASTM work items if they require the absolute latest status.

Q: Is it part of a series?

A: It is developed by ASTM Committee D02 (Petroleum Products, Liquid Fuels, and Lubricants), Subcommittee D02.D0.04, and is part of a group of ASTM oxygenate/ether/alcohol test methods (for example D7754 and D4815) that cover related matrices and concentration ranges.

Q: What are the key keywords?

A: Oxygenates, alcohols, ethers, GC‑FID, multidimensional GC, C2–C5 hydrocarbons, LPG, trace analysis, retention time, calibration, ASTM D7423‑23.