TEG is a colorless, odorless liquid with light viscosity and is a hygroscopic liquid, capable of absorbing moisture and retaining it. It falls under the class of glycol and, therefore, results as a by-product of ethylene glycol during the reaction of ethylene oxide with water. Low volatility and excellent thermal stability make TEG appropriate for applications at high temperatures and where control of moisture is required.

Properties of TEG

Physical state: Colorless, viscous liquid
Odor: Odorless, with a slightly sweet scent possible at high vapor concentrations
Solubility: Miscible with water and many other polar liquids, but not with non-polar liquids like benzene, toluene, and gasoline.
Boiling point: 286.5 °C (at standard atmospheric pressure)
Freezing point: −7 °C
Density: Denser than water
Chemical properties: Stable liquid, hygroscopic (absorbs moisture from the air)

Production Process of Triethylene Glycol (TEG)

The production of TEG begins with the hydration of ethylene oxide, resulting in a mixture of glycols, including:

1. Monoethylene Glycol (MEG)
2. Diethylene Glycol (DEG)
3. Triethylene Glycol (TEG)

Advanced separations, such as fractional distillation, are conducted to isolate TEG from the mixture. Production processes are of high quality, and the end product usually meets industrial grade with a purity percentage of over 99%.

Industrial Standards for TEG:

• Water Content: Less than 0.1%
• Acidity: Below 0.02%
• Purity: ≥ 99%

Various grades of TEG

Technical Grade TEG

• Purity: Typically ranges from 98% to 99% pure, making it suitable for industrial applications where high purity is not critical.
• Applications:  Besides this, there are a lot of applications in the processes of gas dehydration-essentially by absorption of water vapor from natural and other gases. Glycols commonly consist of using as an antifreeze in industrial cooling systems; and in chemical processing solvents.

Electronic Grade TEG

• Purity: Exceeds 99.99% pure, ensuring minimal contamination and residue in electronic components.
• Applications:  It also finds broad applications in electronic industries as a cleaning solvent, mainly in the cleaning of circuit boards, connectors, and other sensitive components. This is a low-residue, high-purity product; thus, it is ideal for avoiding contamination and assuring reliability in electronic devices.

USP Grade TEG

• Purity: Meets the stringent standards set by the United States Pharmacopeia (USP), ensuring it is safe for use in pharmaceutical and cosmetic formulations.
• Applications: It is incorporated into a variety of pharmaceuticals and cosmetics as an active humectant, solvent, and plasticizer. It also contributes to maintaining moisture, improving the feel of formulations, and providing better solubility to the active ingredients.

Food Grade TEG

• Purity: Adheres to the regulations set by the Food and Drug Administration (FDA), making it safe for use in food processing.
• Applications:  A solvent, humectant, and carrier for flavors and colors used in foods. It improves the solubility of ingredients and maintains extended shelf-life, giving many products a uniform texture.

Polymer Grade TEG

• Purity: High purity with specific properties tailored for polymer production.
• Applications:  It is used as a chain extender or cross-linking agent during the synthesis of several polymers, including polyurethanes and polyester resins, in improving their physical and mechanical properties.

Factors Influencing TEG Grade Selection

• Purity: The required level of purity depends on the application. For critical processes like electronics manufacturing or pharmaceutical production, high purity is essential.
• Impurities: The presence of impurities can affect the performance and compatibility of TEG in certain applications.
• Color: The color of TEG may be important for cosmetic or food applications where aesthetics are a concern.
• Viscosity: The viscosity of TEG can influence its flow properties and suitability for specific applications.
• Specific Gravity: The specific gravity of TEG can be relevant for applications where density is a factor.

Application and uses

Natural Gas Dehydration

In the industry of natural gas, TEG is the preferred choice for water vapor removal from gas streams. Its ability to absorb moisture prevents the formation of hydrates and corrosion in pipelines, ensuring efficient and safe transport.

Dehumidification and Air Conditioning

TEG’s moisture-absorbing properties make it indispensable in dehumidifiers and air conditioning systems. It helps maintain optimal humidity levels, improving air quality and preventing damage to sensitive equipment or structures.

Textile Industry

TEG is used as a humectant in the textile industry to control moisture levels during fiber processing. It enhances the quality and durability of fabrics, ensuring smoother production processes.

Chemical Manufacturing

TEG is used as a chemical intermediate in the manufacture of resins, polymers, and plasticizers. The compounds derived from this will be useful in giving strength and flexibility to the products-for example, in the packaging and automotive industries.

Disinfectants and Sanitizers

Due to its low toxicity and solvent properties, TEG is often included in formulations for disinfectants and sanitizers, ensuring effective microbial control in healthcare and industrial environments.

Anti-Freeze Solutions

TEG’s ability to lower the freezing point of water makes it a critical ingredient in anti-freeze and de-icing solutions, particularly in the automotive and aviation industries.

Smoke and Fog Machines

TEG is used in entertainment and industrial applications for generating dense, long-lasting smoke or fog effects in machines, thanks to its stability under high temperatures.

Safety Tips

Personal Protective Equipment (PPE): Always wear gloves, safety glasses, and protective clothing when handling TEG.

Skin Contact: Minimize skin contact with TEG. If contact occurs, wash the affected area thoroughly with soap and water.

Eye Contact: In case of eye contact, flush your eyes immediately with clean water for at least 15 minutes and seek medical attention.

Inhalation: Avoid inhaling TEG vapors. If significant inhalation occurs, move to fresh air and seek medical attention if necessary.

Ingestion: trimethylene glycol ingestion can be harmful. Do not ingest triethylene glycol, and in case of accidental ingestion, call poison control or seek medical attention immediately.

Ventilation: Ensure proper ventilation in areas where trimethylene glycol is handled to minimize airborne concentrations.

Storage: Store TEG in properly labeled, sealed containers in a cool, dry, and well-ventilated place. Keep children and unauthorized personnel out of reach.

Packaging and Storage of TEG

TEG is typically packaged in drums, IBC totes, or bulk tankers to preserve its purity and prevent contamination. Key storage guidelines include:

• Storing in a cool, dry, and ventilated area
• Avoiding exposure to oxidizing agents
• Ensuring containers are tightly sealed to prevent moisture absorption

TECHNICAL DATASHEET of TEG