Naphtha is a product of the petroleum distillation process. It is a light distillate, meaning it comes off early in the distillation and refining process. Naphtha production began around 1860 when 15 U.S. refineries were in operation. Heated by a coal fire, they were called tea kettle stills, consisting of an iron drum connected to a long tube, which acted as a condenser. Naphtha boiled off first, followed by kerosene, then heavy oils and tars. In modern refineries, the main source of naphtha comes from the overhead liquid distillate from the crude oil distillation unit.
Olefinic hydrocarbons that result from processes in some refineries result in olefin-containing naphtha, or cracked naphtha, which is used to produce high-octane elements of gasoline.
Speciality naphthas give rise to a number of products used as solvents, like cleaning fluids, dilution agents for asphalt, paints and varnish. They are also used within the rubber industry and in dry cleaning operations. Alternative names for some of these chemicals are petroleum spirits, white spirit, petroleum ether, varnish makers' and painters' naphtha, white gas or white oil, paraffin, hexanes, benzine and ligroin.
Speciality naphthas are also used in portable camping stoves, lanterns, blowtorches and cigarette lighters as fuel. Because of the bright, clean burn, naphtha is used in performance equipment for fire juggling or fire spinning.
Feedstock for Petrochemical Processes
In steam cracking, naphtha is used as a feedstock to produce petrochemicals like propylene, pyrolysis gasoline and ethylene. In catalytic reforming, it is used to give rise to reformates for benzene, toluene and xylenes, and for gasoline blending. It is usually the heavier naphthas that are used here, like straight run benzene and heavy virgin naphtha.
Paraffinic light naphthas are cracked until the molecules break apart. The resulting hydrocarbons are used to produce plastics like polypropylene and polythene, synthetic fibres like acrylonitrile, and industrial chemicals like glycols. Different kinds of naphthas are also used in shoe polishes and to remove oil from camera aperture blades.