ASTM E1177 Standard Specification for Engine Coolant Grade Glycol

The standard "ASTM E1177 Standard Specification for Engine Coolant-Grade Glycol," developed by the American Society for Testing and Materials (ASTM), covers commercial products, engine coolant-grade ethylene glycol and propylene glycol, including pure glycols, those derived from the recycling of vehicle engine coolants, and glycols from industrial sources. Types EG-1 and PG-1 cover glycols with component limits low enough to allow a blended coolant to meet most original equipment manufacturer (OEM) standards. These types are likely to be pure materials, but redistillation can produce a sufficiently pure product. Types EG-2 and PG-2 cover glycols suitable for many coolants. These types can be either redistilled or pure.

Ethylene glycol or propylene glycol in the engine coolant grade, including pure glycol and those obtained from the recycling of vehicle engine coolants and glycols of industrial origin, must comply with the chemical and physical property requirements in the table titled “Chemical and physical requirements” given in the standard.

For liquid samples, ethylene or propylene glycol is sampled in accordance with ASTM E300 Standard Practice for Sampling Industrial Chemicals. Each composite sample is tested for the chemical and physical requirements listed above.

The ASTM E1177 standard is essential because it ensures the quality, consistency, and safety of glycols used in engine coolants. This standard is considered important for the following reasons:

• Quality assurance: Specifies minimum requirements for the chemical composition and physical properties of ethylene glycol and propylene glycol and ensures that they meet performance expectations in engine cooling systems.
• Compatibility: This standard ensures that glycols are compatible with a variety of engine materials, such as metals, rubbers and plastics, preventing corrosion, degradation or system failure.
• Performance reliability: By specifying purity levels and limiting impurities (e.g. water, chloride or iron), it ensures the ability of glycol to provide effective heat transfer, freeze protection and overflow protection in engines.
• Safety and environmental protection: Addresses potential hazards by setting limits on toxic impurities, ensuring coolant is safe to handle and reducing environmental impact.
• Industry consistency: This standard facilitates trust and interoperability across the automotive and industrial sectors by providing a uniform benchmark for manufacturers, suppliers, and end users.

Without this standard, variations in glycol quality could lead to engine damage, reduced efficiency, safety risks, or environmental damage. It's critical that manufacturers, coolant formulators, and vehicle operators can rely on a consistent, reliable product.

Engine coolant-grade glycol is a high-purity form of glycol, typically ethylene glycol or propylene glycol, that meets specific standards for use in engine coolants. It serves as the primary base fluid in antifreeze/coolant formulations and provides these essential functions:

• Freeze protection: Lowers the freezing point of coolant to prevent engine damage in cold weather.
• Boil-off protection: Increases the boiling point to maintain cooling efficiency under high temperature conditions.
• Heat transfer: Facilitates efficient heat distribution from the engine to the radiator.
• Corrosion prevention: Formulated with additives, it protects engine components (metals, hoses) from corrosion.

To qualify as engine coolant grade, the glycol must have low levels of impurities (e.g., water, chloride, iron) and meet stringent chemical and physical property requirements to ensure performance, compatibility, and safety in automotive and industrial cooling systems.

The raw material used to produce engine coolant-grade glycol is ethylene glycol, a hydrocarbon typically derived from petroleum or natural gas. Ethylene glycol is produced in two ways:

• Ethylene oxidation: Ethylene reacts with oxygen in the presence of a catalyst (e.g., silver) to produce ethylene oxide.
• Hydration: Ethylene oxide is then hydrated with water under controlled conditions (temperature and pressure) to form ethylene glycol.

Propylene glycol, another raw material required for glycol production, is derived from propylene, as well as from petroleum or natural gas, or increasingly from bio-based sources (e.g., glycerin). Propylene glycol is produced in two ways:

• Formation of propylene oxide: Propylene is oxidized to produce propylene oxide, usually via the chlorohydrin process or the hydroperoxide process.
• Hydration: Propylene oxide is hydrated with water, usually under high pressure and temperature, to obtain propylene glycol.

To achieve the high purity required for engine coolant-grade glycol, the raw glycol undergoes several purification steps:

• Distillation: Fractional distillation separates the primary glycol (ethylene or propylene glycol) from water, byproducts (e.g., diethylene glycol), and other impurities. This ensures that the glycol meets purity requirements (e.g., at least 99 percent for engine coolant grade).
• Filtration: Removes particulate matter and residual catalysts.
• Ion exchange or adsorption: Removes trace impurities such as chloride, iron or other ions that can cause corrosion in engines.
• Dehydration: Removes any remaining water to achieve the low water content specified in standards such as ASTM E1177 (usually no more than 0,5 percent).

Our organization, which has been supporting businesses across all sectors for years through a wide range of testing, measurement, analysis, and evaluation activities, has a strong team of employees who closely follow global developments in science and technology and are constantly improving themselves. In this context, we also provide testing services in accordance with the ASTM E1177 Standard Specification for Engine Coolant Grade Glycol.