Petroleum products are materials derived from crude oil (
petroleum) as it is processed in
oil refineries. Unlike
petrochemicals, which are a collection of well-defined usually pure organic compounds, petroleum products are complex mixtures.[1] Most petroleum is converted into petroleum products, which include several classes of fuels.[2]
According to the composition of the crude oil and depending on the demands of the market, refineries can produce different shares of petroleum products. The largest share of oil products is used as "energy carriers", i.e. various grades of
fuel oil and
gasoline. These
fuels include or can be blended to give gasoline,
jet fuel,
diesel fuel,
heating oil, and heavier fuel oils. Heavier (less
volatile) fractions can also be used to produce
asphalt,
tar,
paraffin wax,
lubricating and other heavy oils. Refineries also produce other
chemicals, some of which are used in
chemical processes to produce
plastics and other useful materials. Since petroleum often contains a few percent
sulfur-containing molecules, elemental sulfur is also often produced as a petroleum product.
Carbon, in the form of
petroleum coke, and
hydrogen may also be produced as petroleum products. The hydrogen produced is often used as an intermediate product for other oil refinery processes such as
hydrocracking and
hydrodesulfurization.
Specialty and by-products
Oil refineries will blend various feedstocks, mix appropriate additives, provide short-term storage, and prepare for bulk loading to trucks, barges, product ships, and railcars.[4]
Gasses like
propane and
methane are stored within petroleum.
Liquid fuels blending (producing automotive and aviation grades of gasoline,
kerosene, various aviation turbine fuels, and diesel fuels, adding dyes, detergents, antiknock additives, oxygenates, and anti-fungal compounds as required). Shipped by barge, rail, and tanker ship. May be shipped regionally in dedicated
pipelines to point consumers, particularly aviation jet fuel to major airports, or piped to distributors in multi-product pipelines using product separators called
pipeline inspection gauges ("pigs").
Lubricants (produces light machine oils,
motor oils, and
greases, adding
viscosity stabilizers as required), usually shipped in bulk to an offsite packaging plant.
Paraffin wax, used in illumination (
candlewax) and other uses. May be shipped in bulk to a site to prepare as packaged blocks.
Slack wax, a raw refinery output comprising a mixture of oil and wax used as a precursor for
scale wax and paraffin wax and as-is in non-food products such as
wax emulsions, construction board, matches, candles, rust protection, and vapour barriers.
Bulk
tar shipping for offsite unit packaging for use in tar-and-gravel roofing or similar uses.
Asphalt, used as a binder for
gravel to form
asphalt concrete, which is used for paving roads, lots, etc. An asphalt unit prepares bulk asphalt for shipment.
^Walther W. Irion, Otto S. Neuwirth, "Oil Refining" in Ullmann's Encyclopedia of Industrial Chemistry 2005, Wiley-VCH, Weinheim.
doi:
10.1002/14356007.a18_051