Used Cooking Oil (UCO)

About This Product

Used cooking oil (UCO) is vegetable oil, sometimes with a share of animal fat, that has already served its purpose in frying and food preparation. It is recovered from restaurants, catering kitchens and food processors, then settled, filtered and consolidated by collectors before it enters the feedstock trade. Heat, water released from food and repeated use break part of the triglyceride down into free fatty acids and polar compounds, so UCO resembles its source oils without being identical to them. Its composition depends on what was fried, which oils were used and how carefully the oil was handled after collection. For biodiesel (FAME), UCO is the reference waste feedstock in Europe, but alkaline transesterification tolerates little free fatty acid or water. Plants typically esterify the FFA with methanol over an acid catalyst, or run glycerolysis, before the main reaction, and dry the oil to around 0.1 % water. HVO and HEFA-SPK (SAF) units convert FFA along with the triglycerides, so acidity matters less there; the priority is removing phosphorus, metals, chlorine, nitrogen and polyethylene by degumming, bleaching and fine filtration so that the hydrotreating catalyst is protected. A UCO contract usually fixes FFA as % oleic acid, commonly 5 % maximum with price adjustments above it, and MIU (moisture, insoluble impurities and unsaponifiable matter) at 2–3 %. Iodine value, typically 60–130 g I2/100 g, tracks the frying oils: palm-rich collections sit at the low end and solidify more readily, while sunflower, soybean or rapeseed collections run higher. Sulphur is usually low but matters for biodiesel because the finished ester is limited to 10 mg/kg. HVO and SAF buyers add limits in mg/kg for phosphorus, sodium, potassium, calcium, magnesium, iron, chlorine and polyethylene. UCO is generally discussed as an Annex IX Part B feedstock under the EU Renewable Energy Directive as amended by RED III, which gives it waste-based status but caps its contribution to transport targets. Because that status carries value, UCO is one of the most closely audited feedstocks. Buyers should expect traceability back to registered points of origin, a proof of sustainability issued under a recognised voluntary scheme and documents that fit their own mass-balance records, and should confirm the classification and certificate scope with their certification body before contracting. Tests that reveal an FFA or polymer profile inconsistent with genuinely used oil are a sensible part of acceptance. UCO moves in road tankers, ISO tanks, flexitanks and, for larger parcels, bulk vessels. Palm-rich or fat-rich lots can partly solidify at ambient temperature, so heating coils or heating pads and a discharge temperature should be agreed; avoid prolonged overheating, which raises FFA and darkens the oil. UCO also stratifies in storage, so samples should be drawn through the full depth of each tank or flexitank at loading and at discharge. When you enquire, state the conversion route, the FFA and MIU basis and rejection limits, the contaminants your pretreatment is designed for, the test methods, the monthly or spot volume, the delivery point and Incoterm, and the sustainability documents your market requires. Bio Green Fuels confirms the analysis and available documentation for the specific lot before commercial terms are agreed.