Metal deactivators, or metal deactivating agents (MDA) are

fuel additives A fuel is any material that can be made to react with other substances so that it releases energy as thermal energy or to be used for work. The concept was originally applied solely to those materials capable of releasing chemical energy but ...

and

oil additive Oil additives are chemical compounds that improve the lubricant performance of base oil (or oil "base stock"). The manufacturer of many different oils can utilize the same base stock for each formulation and can choose different additives for each ...

s used to stabilize fluids by deactivating (usually by sequestering) metal

ion An ion () is an atom or molecule with a net electrical charge. The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by conven ...

s, mostly introduced by the action of naturally occurring acids in the fuel and acids generated in

lubricant A lubricant (sometimes shortened to lube) is a substance that helps to reduce friction between surfaces in mutual contact, which ultimately reduces the heat generated when the surfaces move. It may also have the function of transmitting forces, t ...

s by oxidative processes with the metallic parts of the systems. Fuels desulfurized by copper sweetening also contain a significant trace amounts of copper. Metal deactivators inhibit the

catalytic Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recyc ...

effects of such ions, especially

copper Copper is a chemical element with the symbol Cu (from la, cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkis ...

, retarding the formation of gummy residues (e.g.

gel A gel is a semi-solid that can have properties ranging from soft and weak to hard and tough. Gels are defined as a substantially dilute cross-linked system, which exhibits no flow when in the steady-state, although the liquid phase may still di ...

s containing copper mercaptide). Even concentrations of copper as low as 0.1 ppm can have detrimental effects. An example of a metal deactivator used for

gasoline Gasoline (; ) or petrol (; ) (see ) is a transparent, petroleum-derived flammable liquid that is used primarily as a fuel in most spark-ignited internal combustion engines (also known as petrol engines). It consists mostly of organic co ...

and

jet fuel Jet fuel or aviation turbine fuel (ATF, also abbreviated avtur) is a type of aviation fuel designed for use in aircraft powered by gas-turbine engines. It is colorless to straw-colored in appearance. The most commonly used fuels for commercial a ...

s is

salpn } Salpn is the common name for a chelating ligand, properly called ''N'',''N''-bis(salicylidene)-1,2-propanediamine, used as a motor oil additive. The molecular structure of pure (metal-free) salpn, sometimes denoted H2(salpn) or salpnH2, can be ...

. It is used in turbine and

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 engin ...

heating oil Heating oil is any petroleum product or other oil used for heating; a fuel oil. Most commonly, it refers to low viscosity grades of fuel oil used for furnaces or boilers use for home heating and in other buildings. Home heating oil is often a ...

, and greases. It is approved for military and commercial

aviation fuel Aviation fuels are petroleum-based fuels, or petroleum and synthetic fuel blends, used to power aircraft. They have more stringent requirements than fuels used for ground use, such as heating and road transport, and contain additives to enhanc ...

Benzotriazole Benzotriazole (BTA) is a heterocyclic compound with the chemical formula C6H5N3. Its five-membered ring contains three consecutive nitrogen atoms. This bicyclic compound may be viewed as fused rings of the aromatic compounds benzene and triazole. ...

and its various derivatives are also common in

formulas.

References

See also