What is Tall Oil Fatty Acids Rich Distillate? Composition and positioning

Tall Oil Fatty Acids Rich Distillate is a fatty-acid-rich fraction of tall oil distillation. Its acid number is 178.5, saponification number 184 and unsaponifiable matter 5.2%. Total fatty acids up to C18 are reported at 65.6 and total rosin acids at 20.4. It is packed in IBC and ISO tank containers.

What exactly is rich distillate?

Rich distillate is what the name says: a fatty-acid-enriched distillate drawn from the tall oil distillation column. When crude tall oil is distilled, different fractions separate along the column. One is the near-fully-stripped fatty acid grades (TOFA 180 and TOFA 185), another is distilled tall oil (DTO), where a significant rosin acid share remains. Rich distillate sits between them: fatty acid dominates, but the rosin acid fraction has not been stripped out.

That does not make it an academic intermediate. On the contrary, it carries two quantities a formulator actually cares about at once: a high acid number (178.5) and a meaningful rosin acid content (total 20.4). In systems that treat rosin acid as a contribution rather than a defect, having both in the same product shortens the order list.

The real composition profile: what is reported?

Most products in the tall oil family are defined by minimum and maximum limits. Rich distillate instead comes with reported single values, so its composition is given as measurement rather than as a limit. The headline quantities are:

• Acid number: 178.5
• Saponification number: 184
• Unsaponifiable matter by mass: 5.2%
• Fatty acids up to C18 (total): 65.6
• Fatty acids above C18 (total): 1.9
• Rosin acids (total): 20.4
• Total detected: 87.9

The most instructive line is the last one. Total detected is reported as 87.9; this is the sum of the chromatographically identified components and it is not 100%. The product specification does not try to close that gap, and neither do we: the reported total is 87.9, and the component rows should be read against that total. Unsaponifiable matter is given separately at 5.2%.

The fatty acid fraction line by line

The fatty acid side shows the high unsaturation profile characteristic of tall oil. The rows reported by mass in the product specification:

• Linoleic and its isomers: 32.8 + 7.3
• Oleic: 7.5
• Oleic isomers: 7.3
• Linolenic: 6.2
• Palmitic: 3.8
• Stearic: 1.3
• Arachidic: 0.8
• Behenic: 0.7
• Lignoceric: 0.2

The centre of gravity of the profile is linoleic acid and its isomers, with oleic acid and its isomers second. The saturated rows are low (palmitic 3.8, stearic 1.3), and the long-chain saturated total stays low as well: fatty acids above C18 are reported at 1.9 in total. For any system that wants drying or oxidative crosslinking, this dominance of polyunsaturation is the decisive feature.

The rosin acid fraction line by line

The rosin acid side is what separates this product from the TOFA grades. The reported rows:

• Abietic: 6.7
• Palustric: 3.4
• Dehydroabietic: 2.7
• Pimaric: 1.9
• Isopimaric: 1.7
• Neoabietic: 1.1
• Sandaracopimaric: 0.4
• Dihydroabietic: 0.2
• Rosin acids (total): 20.4

The abietic family (abietic, palustric, neoabietic, dehydroabietic, dihydroabietic) weighs clearly more in the total than the pimaric-type rows (pimaric, isopimaric, sandaracopimaric). In practice this means the product's rosin acid contribution behaves close to classic rosin: it adds tack and film hardness, but also brings colour and oxidation sensitivity with it.

Where exactly does it sit between TOFA and DTO?

The shortest way to understand its position is to see three quantities in one table: acid number, rosin acid content and unsaponifiable matter. The table below compares them against the real specification lines of the tall oil family:

The table clarifies three things. First, on acid number, rich distillate (178.5) sits just below the TOFA 180 minimum (180) and clearly above the DTO minimum (170), so on acidity it is close to TOFA. Second, on rosin acid it is far above the TOFA grades but far below the DTO ceiling. Third, unsaponifiable matter at 5.2% is above the TOFA 185 ceiling but below the TOFA 180 and DTO ceilings.

Rich distillate is therefore not a weaker TOFA; it is a product with its own profile. It keeps TOFA's acidity while deliberately carrying the rosin acid fraction. If your formulation does not tolerate rosin acid, TOFA 185 is the right product. If you actually want rosin acid but the DTO max 30% window is too wide, the reported 20.4 of rich distillate gives you a tighter target.

Which production areas use it?

The product's defined production areas map directly onto the composition logic above:

• Alkyd resin production: the high acid number drives esterification while the rosin acid fraction contributes to film hardness.
• Adhesive formulations: the rosin acid content is directly functional on the tack side.
• Industrial chemical synthesis: an acid number of 178.5 and a saponification number of 184 give a defined starting point for reaction stoichiometry.
• Surfactant production: the weight of fatty acids up to C18 (total 65.6) feeds saponification and neutralisation chemistry.
• Metalworking fluids: the fatty acid and rosin acid mix work together on lubricity and film formation.

On packaging, the product is packed in IBC and ISO tank containers. The IBC option offers flexibility that the pure TOFA grades do not have in this family: you can run a qualification batch without committing to a container load.

What should a sample verify?

Because rich distillate is defined by reported single values, what needs verifying at qualification is not limit compliance but how closely your lot tracks the profile. A certificate of analysis (CoA) is issued for every lot; the product is KKDIK-registered (Türkiye) and a Turkish Safety Data Sheet (SDS) is provided.

1. Compare the acid number (178.5) and saponification number (184) on the CoA against your own target range.
2. Match the total rosin acids (20.4) to the ceiling your formulation tolerates.
3. Factor the unsaponifiable matter share (5.2%) into your reaction yield calculation.
4. Read the component rows knowing that total detected is reported as 87.9; do not complete the missing difference yourself.
5. Run a qualification batch at IBC scale first, then move to ISO tank scale.