Petrol additives increase petrol's octane rating or act as corrosion inhibitors or lubricants, thus allowing the use of higher compression ratios for greater efficiency and power. Types of additives include

metal deactivator Metal deactivators, or metal deactivating agents (MDA) are fuel additives and oil additives used to stabilize fluids by deactivating (usually by sequestering) metal ions, mostly introduced by the action of naturally occurring acids in the fuel an ...

s, corrosion inhibitors, oxygenates and antioxidants. Some additives are harmful and are regulated or banned in some countries.

Additives

* Oxygenates ** Alcohols: *** Methanol (MeOH) ***

Ethanol Ethanol (abbr. EtOH; also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound. It is an alcohol with the chemical formula . Its formula can be also written as or (an ethyl group linked to a ...

(EtOH); see also common ethanol fuel mixtures ***

Isopropyl alcohol Isopropyl alcohol (IUPAC name propan-2-ol and also called isopropanol or 2-propanol) is a colorless, flammable organic compound with a pungent alcoholic odor. As an isopropyl group linked to a hydroxyl group ( chemical formula ) it is the s ...

(IPA) *** ''n''-butanol (BuOH) *** Gasoline grade ''t''-butanol (GTBA) **

Ether In organic chemistry, ethers are a class of compounds that contain an ether group—an oxygen atom connected to two alkyl or aryl groups. They have the general formula , where R and R′ represent the alkyl or aryl groups. Ethers can again ...

s: ***

Methyl tert-butyl ether Methyl ''tertiary''-butyl ether (MTBE), also known as methyl tert-butyl ether and ''tert''-butyl methyl ether, is an organic compound with a structural formula (CH3)3COCH3. MTBE is a volatile, flammable, and colorless liquid that is sparingly sol ...

(MTBE), now outlawed in many states of the U.S. for road use because of water contamination. *** Tertiary amyl methyl ether (TAME) *** Tertiary hexyl methyl ether (THEME) *** Ethyl tertiary butyl ether (ETBE) *** Tertiary amyl ethyl ether (TAEE) *** Diisopropyl ether (DIPE) * Antioxidants, stabilizers **

Butylated hydroxytoluene Butylated hydroxytoluene (BHT), also known as dibutylhydroxytoluene, is a lipophilic organic compound, chemically a derivative of phenol, that is useful for its antioxidant properties. BHT is widely used to prevent free radical-mediated oxidat ...

(BHT) **

2,4-Dimethyl-6-tert-butylphenol 2,4-Dimethyl-6-''tert''-butylphenol is the organic compound with the formula Me2(''tert''-Bu)C6H2OH (Me = methyl, ''tert''-Bu = tertiary butyl). It is a colorless oil that is classified as an alkylated phenol. Preparation, reactions, uses I ...

2,6-Di-tert-butylphenol 2,6-Di-''tert''-butylphenol is an organic compound with the structural formula 2,6-((CH3)3C)2C6H3OH. This colorless solid alkylated phenol and its derivatives are used industrially as UV stabilizers and antioxidants for hydrocarbon-based pro ...

(2,6-DTBP) ** p-Phenylenediamine ** N,N'-Di-2-butyl-1,4-phenylenediamine ** Ethylenediamine * Detergents; see also Top Tier Detergent Gasoline **

Amine In chemistry, amines (, ) are compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are formally derivatives of ammonia (), wherein one or more hydrogen atoms have been replaced by a substituent ...

s aka "nitrogen enriched" *** Polybuteneamine (PBA) *** Polyetheramine (PEA); see also Techron *** Polyisobutyleneamine (PIBA) *

Antiknock agent An antiknock agent is a gasoline additive used to reduce engine knocking and increase the fuel's octane rating by raising the temperature and pressure at which auto-ignition occurs. The mixture known as gasoline or petrol, when used in high com ...

s ** Tetraethyllead (TEL), now

banned A ban is a formal or informal prohibition of something. Bans are formed for the prohibition of activities within a certain political territory. Some bans in commerce are referred to as embargoes. ''Ban'' is also used as a verb similar in meanin ...

almost everywhere for causing brain damage. ** Methylcyclopentadienyl manganese tricarbonyl (MMT) is a neurotoxic substance and is fatal if swallowed/inhaled and causes manganism. ** Ferrocene ** Dimethyl methylphosphonate **

Toluene Toluene (), also known as toluol (), is a substituted aromatic hydrocarbon. It is a colorless, water-insoluble liquid with the smell associated with paint thinners. It is a mono-substituted benzene derivative, consisting of a methyl group (CH3) ...

Isooctane 2,2,4-Trimethylpentane, also known as isooctane or iso-octane, is an organic compound with the formula (CH3)3CCH2CH(CH3)2. It is one of several isomers of octane (C8H18). This particular isomer is the standard 100 point on the octane rating sc ...

** Triptane * Lead scavengers (for leaded gasoline) **

Tricresyl phosphate Tricresyl phosphate (TCP), is a mixture of three isomeric organophosphate compounds most notably used as a flame retardant and as a plasticizer in manufacturing for lacquers and varnishes and vinyl plastics. Pure tricresyl phosphate is a colo ...

(TCP) (also an

AW additive AW additives, or antiwear additives, are additives for lubricants to prevent metal-to-metal contact between parts of gears. EP additives are used in applications such as gearboxes, while AW additives are used with lighter loads such as bushings ...

and

EP additive Extreme pressure additives, or EP additives, are additives for lubricants with a role to decrease wear of the parts of the gears exposed to very high pressures. They are also added to cutting fluids for machining of metals. Extreme pressure additi ...

) ** 1,2-Dibromoethane **

1,2-Dichloroethane The chemical compound 1,2-dichloroethane, commonly known as ethylene dichloride (EDC), is a chlorinated hydrocarbon. It is a colourless liquid with a chloroform-like odour. The most common use of 1,2-dichloroethane is in the production of vin ...

* Fuel dyes, most common: **

Solvent Red 24 Sudan IV (C24H20N4O) is a lysochrome (fat-soluble dye) diazo dye used for the staining of lipids, triglycerides and lipoproteins on frozen paraffin sections. It has the appearance of reddish brown crystals with melting point 199 °C and maxim ...

Solvent Red 26 Solvent Red 26, also known as Oil Red EGN or C.I. 26120, is a purplish red synthetic azo dye. It is soluble in oils and insoluble in water. Its main use is as a standard fuel dye in the US mandated by the US IRS to distinguish low-taxed or tax ...

Solvent Yellow 124 Solvent Yellow 124 is a yellow azo dye used in European Union as a fuel dye. It is a marker used since August 2002 to distinguish diesel fuel intended for heating from a higher-taxed motor diesel fuel. It is added to fuels not intended for motor ...

Solvent Blue 35 Oil Blue 35 is a blue anthraquinone dye used for colouring alcoholic and hydrocarbon based solvents, including oils, fats, and waxes. It is used also in lacquers and inks. In some countries, it is used as a fuel dye. It is also used in some blue c ...

* Fuel additives in general **

and other flammable hydrocarbons have been used extensively as

starting fluid Starting fluid is a volatile, flammable liquid which is used to aid the starting of internal combustion engines, especially during cold weather or in engines that are difficult to start using conventional starting procedures. It is typically avail ...

for many difficult-to-start engines, especially

diesel engine The diesel engine, named after Rudolf Diesel, is an internal combustion engine in which ignition of the fuel is caused by the elevated temperature of the air in the cylinder due to mechanical compression; thus, the diesel engine is a so-cal ...

s ** Nitromethane, or "nitro", is a high-performance racing fuel **

Acetone Acetone (2-propanone or dimethyl ketone), is an organic compound with the formula . It is the simplest and smallest ketone (). It is a colorless, highly volatile and flammable liquid with a characteristic pungent odour. Acetone is miscibl ...

is a vaporization additive, mainly used with methanol racing fuel **

Butyl rubber Butyl rubber, sometimes just called "butyl", is a synthetic rubber, a copolymer of isobutylene with isoprene. The abbreviation IIR stands for isobutylene isoprene rubber. Polyisobutylene, also known as "PIB" or polyisobutene, (C4H8)n, is the ...

(as polyisobutylene succinimide, detergent to prevent fouling of

diesel Diesel may refer to: * Diesel engine, an internal combustion engine where ignition is caused by compression * Diesel fuel, a liquid fuel used in diesel engines * Diesel locomotive, a railway locomotive in which the prime mover is a diesel engi ...

fuel injector Fuel injection is the introduction of fuel in an internal combustion engine, most commonly automotive engines, by the means of an injector. This article focuses on fuel injection in reciprocating piston and Wankel rotary engines. All compr ...

s) ** Ferrous picrate is used in Diesel fuel to increase fuel conversion efficiency and reduce emissions.

Racing formulations

* Nitromethane can increase the cetane number of diesel fuel, improving its combustion properties *

Nitrous oxide Nitrous oxide (dinitrogen oxide or dinitrogen monoxide), commonly known as laughing gas, nitrous, or nos, is a chemical compound, an oxide of nitrogen with the formula . At room temperature, it is a colourless non-flammable gas, and ha ...

, or simply ''

nitrous A Nitrous Oxide Engine, or Nitrous Oxide System commonly referred to and known as NOS, is an internal combustion engine in which oxygen for burning the fuel comes from the decomposition of nitrous oxide, N2O, rather than air. The system incre ...

'', is an

oxidizer An oxidizing agent (also known as an oxidant, oxidizer, electron recipient, or electron acceptor) is a substance in a redox chemical reaction that gains or " accepts"/"receives" an electron from a (called the , , or ). In other words, an oxi ...

used in many forms of motorsports such as drag racing and street racing.

Legislation

United States

Fuel additives in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country Continental United States, primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., ...

are regulated unde
section 211
of the Clean Air Act (as amended in January 1995). The Environmental Protection Agency (EPA) requires the registration of all fuel additives which are commercially distributed for use in highway motor vehicles in the

, and may require testing and ban harmful additives. The EPA also regularly reviews the health and net economic benefits of Clean Air Act policies.
Benefits and Costs of the Clean Air Act: a set of scientific reviews conducted by the United States Environmental Protection Agency, U.S. Environmental Protection Agency in compliance with the act. The act also requires deposit control additives (DCAs) be added to all petrol. This type of additive is a detergent additive that acts as a cleansing agent in small passages in the carburetor or

s. This in turn serves to ensure a consistent air and fuel mixture that will contribute to better gas mileage.

References

* ARRC Auto Repair Reference Center. Point 5 Technologies. Accessed via EbscoHost on November 27, 2009
EPA: List of Registered Gasoline AdditivesUnder 40 CFR Part 79
{{DEFAULTSORT:Gasoline Additive Petroleum products Chemistry-related lists

Additives

Racing formulations

Legislation

United States

See also

References