ASTM E2193-23 PDF

Overview

ASTM E2193-23 is the internationally recognized standard test method for determining the ultraviolet (UV) transmittance of monoethylene glycol (MEG) using ultraviolet spectrophotometry. Developed by ASTM International and aligned with World Trade Organization (WTO) principles for standards, this method provides a scientifically rigorous procedure for evaluating the purity of MEG by measuring its transmittance at wavelengths ranging from 220 nm to 350 nm. This test is crucial for ensuring that MEG meets quality specifications, especially where the presence of UV-absorbing contaminants could impact product performance.

Key Topics

• Purpose and Significance

  • Evaluates the purity of MEG in respect to UV absorbing compounds.
  • Determines if MEG products meet required industry and regulatory quality specifications.
  • Supports quality control and assurance in manufacturing and supply chain operations.

• UV Absorption and Contaminants

  • Dissolved oxygen in MEG can shift its main absorption peak from ~180 nm into the measurable UV range (190-250 nm), particularly increasing absorbance at 220 nm.
  • Nitrogen sparging can remove dissolved oxygen, mitigating this effect and helping determine if other contaminants are affecting results.
  • No significant effect from dissolved oxygen is observed in water, simplifying reference spectrum collection.

• Procedure Overview

  • MEG samples are carefully collected to avoid contamination or air exposure.
  • UV spectrophotometric analysis is performed with a 10 mm pathlength cell, measuring transmittance at specified wavelengths.
  • Two sample preparation options: with or without nitrogen sparging.

• Reporting and Quality Control

  • Results are reported to the nearest 0.1% transmittance at each wavelength.
  • Either duplicate results or ongoing statistical quality control is recommended to monitor precision and instrument performance.
  • Quality guidelines are established for laboratories to ensure standard compliance.

Applications

ASTM E2193-23 is widely used in industries and laboratories where MEG’s purity is critical, such as:

• Chemical Manufacturing
  • Ensures feedstock quality for further synthesis and product formulation.
• Antifreeze and Coolant Production
  • Verifies MEG purity to protect engine and industrial equipment from corrosion and fouling.
• Pharmaceuticals and Cosmetics
  • Confirms absence of UV-active impurities that could interfere with end product safety or efficacy.
• Quality Assurance Laboratories
  • Supports in-house and third-party quality management systems, product validation, and regulatory compliance.

Routine use of this test method ensures that products containing monoethylene glycol consistently meet quality benchmarks, reducing the risk of downstream issues related to contamination.

Related Standards

Several ASTM standards are directly referenced in ASTM E2193-23, providing complementary guidelines and terminology relevant to UV spectrophotometry and data quality:

• ASTM D1193: Specification for Reagent Water
• ASTM D6299/D6809: Quality control and statistical analysis for analytical measurement systems
• ASTM E131: Terminology relating to molecular spectroscopy
• ASTM E169: General techniques of ultraviolet-visible quantitative analysis
• ASTM E275: Measuring performance of UV and visible spectrophotometers
• Manufacturer's Spectrophotometer Manual: For specific operational instructions

By following ASTM E2193-23, laboratories benefit from robust, repeatable, and internationally respected procedures for testing monoethylene glycol using ultraviolet spectrophotometry, enhancing product safety, regulatory compliance, and quality assurance processes.

Keywords: ASTM E2193-23, monoethylene glycol, MEG purity, ultraviolet transmittance, UV spectrophotometry, quality control, chemical analysis, industry standards.