TOFA 180 (Tall Oil Fatty Acids 180) is a fatty-acid feedstock that, when saponified with an alkali such as potassium or sodium hydroxide, forms industrial soap; these soaps are used both in cleaning formulations and in metal-working/cutting fluids as a lubricating, emulsifying and corrosion-inhibiting component. Being economical with a high tolerance for rosin and unsaponifiables makes it a suitable feedstock for these cost-sensitive applications.

The saponification reaction: from fatty acid to soap

Saponification (of the neutralization type) is the reaction of a fatty acid with a base to form a fatty-acid salt (soap) and water. The free fatty acids of TOFA 180 convert to potassium soaps with potassium hydroxide (KOH) and to sodium soaps with sodium hydroxide (NaOH). Potassium soaps are softer and more readily water-soluble (tending toward liquid soap), while sodium soaps are harder.

TOFA 180's acid value of at least 180 mg KOH/g directly determines the amount of alkali required for saponification and the soap yield obtained; the higher the acid value, the more soap is produced per given mass of TOFA. The max. 3% rosin and max. 6% unsaponifiables tolerance is suitable for industrial soaps where color and purity are not critical.

Its role in metal cutting and working fluids

Metalworking fluids (machining, rolling, drawing) are used to cool the cutting tool and workpiece, reduce friction and protect the machined surface from corrosion. Soaps derived from TOFA 180 serve several functions in these fluids:

  • Lubrication: fatty-acid soaps form a film on the metal surface providing boundary lubrication, reducing friction and tool wear.
  • Emulsifier: in semi-synthetic and soluble-oil cutting fluids, they keep the oil phase as a stable emulsion in water.
  • Corrosion inhibition: fatty-acid soaps adsorb onto the iron surface to form a protective layer and delay rust formation.
  • Concentrate structure: used as an emulsifier/lubricant carrier within a concentrate suitable for dilution.
FunctionContribution of the TOFA 180-derived soap
CoolingSupports carrying of the water phase (emulsion stability)
LubricationSurface film for boundary lubrication
Corrosion inhibitionProtective adsorption layer on the iron surface
Emulsion stabilityEmulsifier at the oil-water interface

Dilution and emulsion

Soluble-oil and semi-synthetic cutting fluids are usually supplied as a concentrate and diluted with water at the point of use. TOFA 180 soaps act as emulsifiers in this concentrate so that, when the concentrate is added to water, a stable milky-looking emulsion (macroemulsion) forms. Water hardness, pH and dilution ratio affect emulsion stability; in the formulation they are usually used together with pH buffers and additional corrosion inhibitors.

BİO BAZLI ÜRÜNLERTall Oil Fatty Acids 180 (TOFA)KORKİMYA supplies TOFA 180 as a technical grade in bulk (ISO tank) to manufacturers of industrial soap and metalworking fluids.

Depending on formulation requirements, related tall-oil derivatives such as tall oil fatty acids rich distillate can also be considered in soap and emulsifier chemistry; the fatty-acid/rosin balance varies by product.

Safe handling and storage

TOFA 180 is a combustible organic liquid, while saponification is carried out with strong, corrosive alkalis such as KOH or NaOH that react exothermically. When handling the alkali and the reaction mixture, use chemical-resistant gloves, eye/face protection and ventilation against splashing and heat release, and add the alkali in a controlled manner. Keep TOFA 180 away from heat and ignition sources and follow all relevant SDS documents.
  • Store TOFA 180 in closed containers in a cool, dry, well-ventilated area; keep away from oxidizers.
  • Can be stored in bulk in carbon-steel or stainless-steel tanks.
  • Shelf life is 12 months and can be extended to 24 months following a quality-control test.
  • Because of its unsaturated structure, prolonged air exposure can darken the color; keep containers tightly closed.
Is TOFA 180 saponified with KOH or NaOH?

Either can be used. KOH gives potassium soaps (softer, tending toward liquid soap) and NaOH gives sodium soaps (harder). The choice is made according to the desired soap hardness and solubility.

What does TOFA 180 do in a metal cutting fluid?

Its derived soaps act simultaneously as a lubricant (boundary lubrication), an emulsifier (keeping the oil-water emulsion stable) and a corrosion inhibitor (a protective layer on the iron surface).

How is a cutting-fluid concentrate diluted?

The concentrate is diluted with water at a set ratio at the point of use. TOFA 180 soaps act as emulsifiers to form a stable milky emulsion; water hardness, pH and dilution ratio affect emulsion stability.

How does an acid value of 180 affect soap yield?

Acid value measures the free fatty-acid content per gram. A minimum of 180 mg KOH/g determines the amount of soap obtainable from a given mass of TOFA and the alkali dose required; the higher the acid value, the higher the yield.