Biodiesel

A clean, renewable alternative to fossil diesel — produced from waste cooking oil, vegetable oils and animal fats, and usable in standard diesel engines.

Biodiesel is an alternative fuel similar to conventional or “fossil” diesel. It can be produced from straight vegetable oil, animal oils and fats, tallow and waste cooking oil. Most biodiesel produced in Sri Lanka today comes from waste vegetable oil sourced from restaurants — turning a disposal problem into a fuel.

Feedstock

Common feedstocks include yellow grease (recycled vegetable oil), virgin vegetable oil, and tallow. Recycled oil is processed to remove impurities from cooking, storage and handling — dirt, charred food and water. Virgin oils are refined, though not to food grade; degumming to remove phospholipids and plant matter is common, with refinement processes varying by source.

Production

A sample of the cleaned feedstock is titrated with a standardised base solution to determine the concentration of free fatty acids present in the oil. These acids are then esterified into biodiesel, esterified into glycerides, or removed through neutralisation — yielding a fuel that runs in standard diesel engines with little or no modification.