CAS 61790-12-3 is the registry number for tall oil fatty acids (TOFA). It does not identify a single molecule but a mixed blend obtained by distilling crude tall oil, consisting predominantly of C18 fatty acids. The CAS number alone therefore does not define the product: acid value, rosin acid and unsaponifiables limits define the grade.
What exactly does CAS 61790-12-3 cover?
For most chemicals a CAS number points to one defined molecule. Tall oil fatty acids are different: 61790-12-3 covers a substance group coming out of a defined production process, that is, a UVCB-type mixture. In the KORKİMYA portfolio, TOFA 180 and TOFA 185 carry the same CAS number and are described in the formula field as a "mixed blend (predominantly C18 fatty acids)" and a "complex blend (predominantly C18 fatty acids)" respectively.
The practical consequence: an order, a customs declaration or a supplier comparison cannot be made on the CAS number alone. Two different grades under the same CAS number behave entirely differently on your line. The CAS number confirms identity; the grade determines performance.
Composition: the fatty acid fraction and the rosin acid fraction
When crude tall oil (CTO) enters fractional distillation it yields three main outputs: a fatty acid fraction (TOFA), a rosin acid fraction and pitch as the bottoms product. TOFA is the fatty acid side of that split and consists predominantly of fatty acids in the C18 chain length.
Because the split is never perfect, the TOFA specification is defined by rosin acid and unsaponifiables limits. Those two lines are the measurable answer to the question of how sharply the distillation was run:
- Rosin acid content (ASTM D1240): the share of abietic-type rosin acids remaining in the fatty acid fraction. Max 3% in TOFA 180, max 2% in TOFA 185.
- Unsaponifiables (ASTM D1065): residual components that do not enter the saponification reaction. Max 6% in TOFA 180, max 4% in TOFA 185.
- Acid value (ASTM D1980): the direct measure of free fatty acid content. Min 180 in TOFA 180, min 185 in TOFA 185.
- Iodine value (ASTM D5768): the level of unsaturation in the chains; min 150 in both grades.
Specification lines and the ASTM methods behind them
These are the lines you will see on a TOFA certificate of analysis and the methods behind them. A line without a method reference produces different results in different laboratories and turns into a dispute at validation:
In Turkish documents the product is also called "çam yağı yağ asitleri": "Çam Yağı Yağ Asitleri 180" for TOFA 180 and "Çam Yağı Yağ Asitleri 185" for TOFA 185. Using these synonyms together with the CAS number on orders and customs paperwork prevents a mismatch.
BİO BAZLI ÜRÜNLERTall Oil Fatty Acids 180 (TOFA)TOFA 180 under CAS 61790-12-3: acid value min 180 (ASTM D1980), rosin acid max 3% (ASTM D1240). Request a sample with a per-lot CoA and a Turkish SDS.Storage and handling conditions
TOFA is stored as a liquid in a closed system. The defined conditions for the two grades in the KORKİMYA portfolio are:
- TOFA 180: 20-40 °C in closed tanks; avoid direct sunlight and low-humidity environments.
- TOFA 185: 20-40 °C in closed containers; avoid direct sunlight and moisture.
- Preferred tank material: carbon steel or stainless steel for both grades.
- Shelf life: 12 months, extendable to 24 months with quality control testing.
- Shipment mode: bulk liquid in ISO tank containers; 20-24 MT net for TOFA 180 and 20-22 MT net for TOFA 185.
What to expect on the documentation side
- Certificate of analysis (CoA) per lot: the measured values of the delivered batch with method references.
- Turkish Safety Data Sheet (SDS): hazard classification, handling, storage and transport.
- KKDIK registration (Türkiye): in place for TOFA 180 and TOFA 185.
- Identity confirmation: CAS 61790-12-3 and the blend description stated on the document.
These four items are the minimum set needed for both lab qualification and a QHSE audit. Requesting them together with a sample lets you validate before the purchase decision.
BİO BAZLI ÜRÜNLERTall Oil Fatty Acids 185 (TOFA)TOFA 185 under CAS 61790-12-3: acid value min 185 (ASTM D1980), unsaponifiables max 4% (ASTM D1065). Request a sample, the CoA and a current quote from the product page.Which substance does CAS 61790-12-3 identify?
Tall oil fatty acids (TOFA). It covers not a single molecule but a mixed blend obtained by distilling crude tall oil, consisting predominantly of C18 fatty acids.
Do TOFA 180 and TOFA 185 share the same CAS number?
Yes, both fall under CAS 61790-12-3. The difference is not in the CAS number but in the specification: acid value min 180 versus min 185, rosin acid max 3% versus max 2%, unsaponifiables max 6% versus max 4%.
Is quoting only the CAS number enough when ordering?
No. Different grades exist under the same CAS number and behave differently on your line. Alongside the CAS number, state the grade and the critical specification lines (acid value, rosin acid, unsaponifiables, appearance) with their method references.
Which methods are the specifications measured by?
Acid value by ASTM D1980, iodine value by ASTM D5768, rosin acid content by ASTM D1240 and unsaponifiables by ASTM D1065. Appearance is assessed visually.
What are the shelf life and storage conditions?
Shelf life is 12 months and can be extended to 24 months with quality control testing. The product is stored at 20-40 °C in closed containers, protected from direct sunlight and moisture, preferably in carbon or stainless steel tanks.
Which documents are provided?
A certificate of analysis (CoA) per lot, a Turkish Safety Data Sheet (SDS) and KKDIK registration. You can request the documents at the sample stage.