Product Overview

Hydrogenated terphenyls, CAS 61788-32-7, is a partially hydrogenated mixture of ortho, meta and para terphenyl isomers produced by catalytic hydrogenation with a saturation degree of about 40 percent. At room temperature it is a clear, pale yellow oily liquid with a faint odor, practically insoluble in water. It is designed as a liquid phase high temperature synthetic heat transfer fluid, offering a wide operating window from roughly minus 12 C up to 345 C with a very low vapor pressure at the upper end of that range.

Key Attributes

Key Highlights

• WIDE TEMPERATURE WINDOW: Operates in the liquid phase from about minus 12 C up to 345 C, covering both low temperature pumping and high temperature heating duties in a single charge of fluid.
• EXCELLENT THERMAL STABILITY: The partially hydrogenated polyphenyl structure resists thermal cracking, which keeps sludge formation low and extends the service life of the fluid in closed loop systems.
• LOW VAPOR PRESSURE AT HIGH TEMPERATURE: Vapor pressure remains close to 75 kPa even at 345 C, so the system can run at low operating pressure without pressurized equipment.
• LOW FREEZING POINT: Freezing point around minus 30 C to minus 32 C allows cold weather storage and pumpability without trace heating in most climates.
• GOOD OXIDATION RESISTANCE: Hydrogenation reduces the reactive aromatic sites, which slows oxidation and helps hold the acid value and viscosity within specification during long operating cycles.
• CONSISTENT BATCH QUALITY: Every batch is released against a fixed specification covering appearance, density, viscosity, distillation range and freezing point, with a COA issued per shipment.
• FLEXIBLE PACKAGING: Supplied in 200 L steel drums, 1000 L IBC containers or bulk ISO tank for full container and vessel quantities.
• BULK SUPPLY CAPABILITY: Minimum order quantity of 1 metric ton, shipped within 3 weeks after order confirmation, serving regular contract buyers worldwide.

Product Description

Hydrogenated terphenyls is produced by partial catalytic hydrogenation of a mixed ortho, meta and para terphenyl stream. The hydrogenation is controlled to a saturation degree of about 40 percent, which balances thermal stability against low temperature fluidity. The finished product is a mixture of hydrogenated terphenyl isomers together with small amounts of unreacted terphenyls and higher hydrogenated polyphenyls, and it is supplied as an industrial grade synthetic heat transfer fluid.

The key performance advantage of this chemistry is that it stays in the liquid phase at temperatures where mineral oils and many alkylated aromatic fluids have already degraded. At 345 C the vapor pressure is still only about 75 kPa, so heat can be delivered at high temperature under essentially atmospheric system pressure. Combined with a freezing point near minus 30 C, this gives a single fluid a working range of more than 350 C, which is why hydrogenated terphenyls has been the standard choice for high temperature closed loop heating systems for decades.

In service the fluid shows low fouling tendency and low corrosivity toward carbon steel and stainless steel system components. Its oxidation resistance keeps the acid value low over long operating periods, which reduces the rate of viscosity increase and the frequency of fluid replacement. The pale color of the fresh fluid also makes contamination and degradation easier to detect during routine visual inspection.

Dideu Group supplies hydrogenated terphenyls in drum, IBC and bulk quantities with a minimum order of 1 metric ton and a standard lead time within 3 weeks after order confirmation. Each shipment is accompanied by a certificate of analysis covering the full specification table below, and technical documents including the technical data sheet are provided on request.

Applications

Petrochemical and Refining. Used as the heating medium for synthesis reactors, distillation and rectification columns, fraction preheating, tank heating and heavy oil heating, where stable heat input at 280 C to 345 C is required over long continuous campaigns.

Synthetic Fibers and Polyester. Applied in polycondensation and polymerization heating for polyester and polyamide production, melt spinning, heat setting, stretching and drying. Low vapor pressure at high temperature makes it suitable for the final polycondensation stage.

Fine and Specialty Chemicals. Serves as the heat carrier for silicone monomer synthesis, trichlorosilane and polysilicon production, and for pharmaceutical, agrochemical and dye intermediate processes that need precise and clean high temperature heat.

Solar Thermal Power and Energy Storage. Employed as the heat transfer fluid in concentrated solar power plants and thermal energy storage loops, where the wide liquid range supports both daytime heat collection and nighttime discharge.

Plastics and Rubber. Provides uniform heat for hot pressing, calendering, extrusion and vulcanization molding lines, helping to hold tight temperature profiles across large platens and dies.

Textile Printing and Dyeing. Used in heat setting, drying and curing ovens where even temperature distribution directly affects shade reproducibility and fabric hand.

Oils, Fats and Biodiesel. Applied in fat splitting, deodorization, fatty acid distillation, hydrogenation and esterification, as well as in biodiesel production units requiring high temperature heat input.

Paints, Coatings and Inks. Supplies heat for baking, drying and high temperature curing of coil coatings, can coatings and printing inks.

Wood Processing and Panel Manufacturing. Used for hot pressing, drying and forming of plywood, particle board and other engineered wood panels.

Electronics and Electrical Applications. The high dielectric strength and thermal stability of the polyphenyl structure make it a candidate for use as a capacitor impregnant, an electronic component encapsulation aid and a high temperature dielectric heat exchange medium.

Other Applications. Also used as a component in precision casting release agents, as a binder constituent in blast furnace plug mud formulations, and as a high temperature heat bath medium in laboratory and pilot scale synthesis, including nanomaterial preparation.

Specifications

Packaging and Shipping

Storage recommendations

• Keep containers tightly closed when not in use.
• Store in a cool, dry and well ventilated warehouse, away from direct sunlight and heat sources.
• Protect from moisture and rain water ingress during outdoor storage.
• Use dedicated pumps and lines to avoid cross contamination with other fluids.

Mode of transport: by sea, in drums, IBC or bulk ISO tank.

Lead time: within 3 weeks after order confirmation.

Minimum order quantity: 1 metric ton.

Company Profile

Dideu Group is a professional supplier of fine chemicals and specialty chemicals, serving customers in global markets with a full range of products from lab scale reagents to industrial quantities. Our product portfolio covers heat transfer fluids, specialty solvents, organic intermediates, inorganic salts and custom chemical raw materials for the petrochemical, polymer, coating, electronics and pharmaceutical industries. We work with qualified manufacturing partners and run incoming and outgoing quality checks so that every consignment is released against a documented specification. Our export team handles documentation, packaging and logistics in house, which allows us to keep lead times predictable for repeat buyers. Buyers receive a certificate of analysis with each shipment, and technical data sheets are available on request. We aim to build long term supply relationships rather than single transactions, and we are glad to discuss annual contracts and framework agreements.

FAQ

1. What is the minimum order quantity?

The minimum order quantity for hydrogenated terphenyls is 1 metric ton. Larger contract quantities can be arranged on an annual or framework basis.

2. What is the lead time?

Dideu ships within 3 weeks after order confirmation, subject to the quantity and the packaging format selected.

3. What packaging options do you offer?

The product is supplied in 200 L steel drums, 1000 L IBC containers or bulk ISO tanks. Packaging can be matched to your unloading equipment and storage layout.

4. What payment terms do you accept?

We accept T/T and L/C. Terms for first orders and for long term contracts can be discussed with our sales team.

5. Do you provide a COA and technical documents?

Yes. A certificate of analysis is issued for every batch, covering appearance, density, viscosity, distillation range, freezing point, flash point and refractive index. The technical data sheet is available on request.

6. How do you ship the goods?

Shipments are made by sea. Drum and IBC orders move in containers, while bulk orders are shipped in ISO tanks.

7. What temperature range can this fluid cover in service?

The recommended service window runs from about minus 12 C to 345 C in the liquid phase, with a freezing point near minus 30 C for cold start and storage conditions.