An ionic liquid piston compressor, ionic compressor or ionic liquid piston pump is a hydrogen compressor based on an

ionic liquid An ionic liquid (IL) is a salt in the liquid state. In some contexts, the term has been restricted to salts whose melting point is below a specific temperature, such as . While ordinary liquids such as water and gasoline are predominantly made of ...

piston instead of a metal piston as in a piston-metal

diaphragm compressor {{Short description, Variant of the reciprocating compressor A diaphragm compressor is a variant of the classic reciprocating compressor with backup and piston rings and rod seal. The compression of gas occurs by means of a flexible membrane, instea ...

Principle

An ionic liquid compressor takes advantage of two properties of ionic liquids—their virtually non-measurable

vapor pressure Vapor pressure (or vapour pressure in English-speaking countries other than the US; see spelling differences) or equilibrium vapor pressure is defined as the pressure exerted by a vapor in thermodynamic equilibrium with its condensed phase ...

s and large temperature window for the liquid phase—in combination with the low solubility of some gases (e.g.

hydrogen Hydrogen is the chemical element with the symbol H and atomic number 1. Hydrogen is the lightest element. At standard conditions hydrogen is a gas of diatomic molecules having the formula . It is colorless, odorless, tasteless, non-toxic ...

) in them. This insolubility is exploited by using the body of an ionic liquid to compress hydrogen up to 1000bar (14,500psi) in hydrogen filling stations. Linde's ionic liquid compressor reduced the number of moving parts from about 500 in a conventional

reciprocating compressor A reciprocating compressor or piston compressor is a positive-displacement compressor that uses pistons driven by a crankshaft to deliver gases at high pressure. Pressures of up to 5,000 PSIG are commonly produced by multistage reciprocating c ...

down to 8. Many seals and bearings were removed in the design as the ionic liquid does not mix with the gas.

Service life A product's service life is its period of use in service. Several related terms describe more precisely a product's life, from the point of manufacture, storage, and distribution, and eventual use. Service life has been defined as "a product's ...

is about 10 times longer than a regular reciprocating compressor with reduced maintenance during use, energy costs are reduced by as much as 20%. The heat exchangers that are used in a normal piston compressor are removed as the heat is removed in the cylinder itself where it is generated. Almost 100% of the energy going into the process is being used with little energy wasted as reject heat. Not to be confused with the ion pump or the ionic liquid ring pump.

History

After the renewed interest in ionic liquids, research was done by proionic, an enterprise in the spin-off center "ZAT Center for applied Technology" of the

University of Leoben The University of Leoben (German: ''Montanuniversität Leoben'') in Austria is the country's university for mining, metallurgy and materials. It was founded on 4 November 1840 as the ''Steiermärkisch-Ständische Montanlehranstalt'' in Vordernb ...

. The system was demonstrated at Zemships.Zemships - Ionic liquid compression

References

{{DEFAULTSORT:Ionic Liquid Piston Compressor Gas compressors Hydrogen technologies

Principle

History

See also

References