99% of all plastics are derived from oil and natural gas. Currently, most of them are manufactured using naphtha feedstock, which is itself a product of the oil-refining process. While transforming crude oil into motor fuels, refineries also produce a wide variety of other products ranging from light gases such as butane and propane to heavier substances such as bitumens. One of these products is naphtha, which is heavier than gasoline (petrol).
This naphtha is fed into a steam cracker that breaks down the hydrocarbons in naphtha into lighter molecules – ethylene (C2) and propylene (C3) – now containing only a few carbon atoms. These are the base chemicals used in the petrochemicals industry, the substances that will later become plastics.
In petrochemicals plants, these so-called monomers are then agglomerated to form giant molecules containing thousands of carbon atoms. These are called polymers. They can be produced in a variety of forms: powder, granules, flakes, paste or liquid. These polymers are later transformed into plastics items using different processes such as extrusion, roto-molding, blow-molding, etc.
Total manufactures the base chemicals and three polymers: two polyolefins (polyethylene and polypropylene) and a styrenic polymer (polystyrene).