Soybean Acid Oil

About This Product

Soybean acid oil comes from the chemical refining of soybean oil, one of the largest-volume vegetable oils in world trade. Crude soybean oil is rich in phospholipids, so refineries degum it before or during neutralisation with caustic soda. The soaps formed from its free fatty acids are separated as soapstock and split with sulphuric acid, leaving a dark, high-FFA oil. Because the soapstock also collects entrained neutral oil and, depending on the refinery's layout, part of the gums, soybean acid oil can vary considerably from one refinery to another even though its fatty acid profile is well defined. That profile is dominated by linoleic acid, typically around half of the fatty acids, with oleic, palmitic and some linolenic acid. The result is a high iodine value, typically about 115–135 g I2/100 g, and good cold-flow behaviour in the finished ester, balanced by lower oxidation stability. FAME made from soybean acid oil therefore often needs antioxidant treatment to meet the EN 14214 oxidation stability requirement, and blending with more saturated feedstocks helps keep iodine value below the standard's limit of 120. For biodiesel, FFA of typically 50–80 % means acid esterification, glycerolysis or ester distillation is needed alongside transesterification. For HVO and HEFA-SPK (SAF) the FFA is acceptable, but the high degree of unsaturation increases hydrogen consumption compared with palm-based or animal-fat feedstocks. In both routes, pretreatment has to deal with phosphorus and residual sodium soap carried over from the refinery, and with sulphate left from acidulation. Contracts usually specify TFM (commonly 90–95 % or more), MIU (often up to 3–5 %), FFA as % oleic acid, iodine value, sulphur and phosphorus. Sulphur can run from tens to hundreds of mg/kg when washing after acidulation is incomplete. HVO buyers add sodium, calcium, magnesium, iron and chloride limits in mg/kg. Soybean acid oil is not named in Annex IX of the Renewable Energy Directive. It is discussed as a processing residue in some RED III transpositions and treated as a co-product, or excluded from incentives, in others, and some markets apply specific rules to soy-derived material. Confirm the classification and the certificate scope with your certification body, and check that the traceability documents identify the originating refinery and fit your mass-balance records. The oil is usually liquid at ambient temperature but thick and dark. It ships in flexitanks with confirmed liner compatibility, in lined or stainless ISO tanks and in bulk parcels. When enquiring, specify the TFM and MIU basis, FFA, iodine value range, sulphur and phosphorus caps, conversion route, volume, packaging and delivery terms, and the sustainability documents you need.