List of gasoline additives

Gasoline additives increase gasoline'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 deactivators, corrosion inhibitors, oxygenates and antioxidants.

Some additives are harmful, and are regulated or banned in some countries.

Additives

• Oxygenates
  • Alcohols:
    • Methanol (MeOH)
    • Ethanol (EtOH)
    • Isopropyl alcohol (IPA)
    • n-butanol (BuOH)
    • Gasoline grade t-butanol (GTBA)
  • Ethers:
    • Methyl tert-butyl ether (MTBE), now outlawed in many states of the U.S. for road use, mostly 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 (BHT)
  • 2,4-Dimethyl-6-tert-butylphenol
  • 2,6-Di-tert-butylphenol (2,6-DTBP)
  • p-Phenylenediamine
  • Ethylene diamine

• Antiknock agents
  • Tetraethyllead, now banned almost everywhere for causing brain damage and violent crime.
  • Methylcyclopentadienyl manganese tricarbonyl (MMT)
  • Ferrocene
  • Iron pentacarbonyl
  • Toluene
  • Isooctane
  • Triptane

• Lead scavengers (for leaded gasoline)
  • Tricresyl phosphate (TCP) (also an AW additive and EP additive)
  • 1,2-Dibromoethane
  • 1,2-Dichloroethane

• Fuel dyes, most common:
  • Solvent Red 24
  • Solvent Red 26
  • Solvent Yellow 124
  • Solvent Blue 35

• Fuel additives in general
  • Ether and other flammable hydrocarbons have been used extensively as starting fluid for many difficult-to-start engines, especially diesel engines
  • Nitrous oxide, or simply nitrous, is an oxidizer used in auto racing
  • Nitromethane, or "nitro," is a high-performance racing fuel
  • Acetone is a vaporization additive, mainly used with methanol racing fuel to improve vaporisation at start up
  • Butyl rubber (as polyisobutylene succinimide, detergent to prevent fouling of diesel fuel injectors)
  • Picrate improves combustion, increases fuel mileage
  • Silicone is an anti-foaming agent for diesel fuel, but may damage oxygen sensors in gasoline engines
  • Tetranitromethane can increase the cetane number of diesel fuel, improving its combustion properties

Legislation

United States

Fuel additives in the United States are regulated under 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 United States,^[1] and may require testing and ban harmful additives. The EPA also regularly reviews the health and net economic benefits of Clean Air Act policies.^[2]

The act also requires deposit control additives (DCAs) be added to all gasolines. This type of additive is a detergent additive that acts as a cleansing agent in small passages in the carburetor or fuel injectors. This in turn serves to ensure a consistent air and fuel mixture that will contribute to better gas mileage.

See also

• For additive metering see metering pumps
• Biobor (microbicide)
• Oil additive, which describes some similar additives
• Top Tier Detergent Gasoline

References

• ARRC Auto Repair Reference Center. Point 5 Technologies. Accessed via EbscoHost on November 27, 2009