ASTM D2712-23 PDF

Overview

ASTM D2712-23: Standard Test Method for Determination of Hydrocarbon Impurities in High Purity Propylene by Gas Chromatography is an internationally recognized protocol developed by ASTM. This method is essential for analyzing hydrocarbon impurities in propylene (propene) material with a purity of 97% by mass or greater. The presence of trace hydrocarbon contaminants in high-purity propylene can negatively impact manufacturing yields, catalyst lifespan, and overall product quality. Applying this standard increases the reliability of feedstock materials used in the petrochemical industry, supports quality control, and helps set commercial specifications for propylene.

Key Topics

• Hydrocarbon Impurity Detection: This standard focuses on the precise determination of trace-level hydrocarbon impurities-including methane, ethane, ethylene, propane, acetylene, isobutane, butenes, isopentane, methylacetylene, pentanes, and 1,3-butadiene-within a quantification range of 0.35 mg/kg to 8575 mg/kg.

• Gas Chromatography (GC) Technique: The analysis employs gas chromatography equipped preferably with a flame ionization detector (FID) for high sensitivity and selectivity. Specialized sample introduction systems, such as liquid or vapor sampling valves and the use of pre-columns, help ensure effective separation and accurate quantification.

• Sample Preparation and Calibration: Guidelines are provided for proper sample collection (using floating piston sample cylinders to prevent volatilization and headspace formation) and for calibration using certified external standard mixtures. The purity of propylene is measured by subtracting the total impurities detected from 100% by mass.

• Quality Assurance: The methodology supports routine benchmarking, process control, and R&D in order to maintain the performance expectations of high-purity propylene across industrial applications.

• Safety Considerations: The procedure handles hazardous materials under pressure and requires robust safety, health, and environmental practices. Personnel should receive LPG sampling safety training and observe all applicable regulatory requirements.

Applications

• Feedstock Qualification: Used by propylene producers and processors to certify high-purity feedstocks for sensitive polymerization reactions and production of chemical intermediates.
• Commercial Specification Setting: Provides a technical basis for defining and verifying impurity limits in supply contracts, securing confidence in material quality for both buyers and sellers.
• Quality Control and Assurance: Integrates into plant laboratory workflows for continuous monitoring of product streams, helping to quickly identify off-spec batches and minimize process disruptions.
• Process Development and Research: Utilized in research laboratories and pilot plants to evaluate the effect of trace impurities on catalyst activity, polymer properties, and overall process efficiency.

Related Standards

• ASTM D1265: Practice for Sampling Liquefied Petroleum (LP) Gases, Manual Method - Guidance for correct sampling techniques supporting D2712-23.
• ASTM D1835: Specification for Liquefied Petroleum (LP) Gases - Specifies composition and impurity levels for commercial LPG products.
• ASTM D3700: Practice for Obtaining LPG Samples Using a Floating Piston Cylinder - Describes recommended sampling containers referenced in D2712-23.
• ASTM E355: Practice for Gas Chromatography Terms and Relationships - Provides definitions and terminology pertinent to GC analysis.
• ASTM F307: Practice for Sampling Pressurized Gas for Gas Analysis - Alternative procedures for safe and effective gas sample collection.

By following ASTM D2712-23, industries ensure accurate detection of hydrocarbon impurities, supporting stringent quality standards for propylene feedstocks. Its adoption drives process optimization and regulatory compliance across the petrochemical sector.