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Bioniqs patented range of liquid ammonium salts (LAS) solvents are classed as protic ionic liquids. In response to customers queries we have put together some information to introduce our class of ionic liquid materials:

What are ionic liquids?
Ionic liquids are materials composed predominantly of ions, which are liquid at or below room temperature. Whereas most ionic compounds, such as sodium chloride, are high melting solids (salts), some combinations of ions exist in a liquid state under ambient conditions.

Why are they liquid?
The attractive forces between the positively and negatively charged component ions in ionic liquids are weakened through a combination of charge delocalization, asymmetry and other factors. Correct selection of an anion/cation combination can result in ionic compounds, which remain in the liquid state at temperatures as low as –80°C.

Why are ionic liquids useful solvents?
Ionic liquids exhibit a number of remarkable properties: they are of low volatility, generally non-flammable, often possess near zero vapour pressure and can dissolve extremely high concentrations of a wide variety of materials, from organic compounds such as fats, oils and pharmaceuticals to metallic compounds, polymers and even minerals.

What are “liquid ammonium salts”?
In between a purely ionic liquid and a purely molecular liquid (such as hexane or ether), there exist a number of liquids with intermediate characteristics, such as LAS. These can be considered as Protic Ionic Liquids (PILs) and are composed partly of ions, partly of molecules. When a primary, secondary or tertiary amine is neutralized by an acid, a salt is formed. They are composed primarily of ions and an equilibrium exists between the charged ions and the neutral (amine and acid) molecules. Liquid ammonium salts are primarily ionic liquids with a molecular component.

What are the benefits of LAS?
In general, they tend to be of much lower viscosity than comparable ionic liquids, are easier to recycle and – crucially – can be manufactured with great ease by simple neutralization of a cheap, readily available, non-toxic amine with a similarly desirable acid. These solvents therefore provide a route around several of the major disadvantages of fully ionic liquids, whilst retaining many of their most desirable characteristics as solvents.


A huge range of ammonium salts with melting points below room temperature are known and Bioniqs has established intellectual property around their use as solvents. This large range gives considerable flexibility in terms of selecting the optimal combination of properties for a defined application. Liquid ammonium salts thus represent a major group of alternative solvents for industry with unique properties distinct from those of any other commonly available materials.

Why are ionic liquids called "green" solvents?
Ionic liquids are often considered to be environmentally friendly solvents. The most frequently cited property supporting this assertion is their generally very low volatility, they tend not to evaporate and hence contamination issues associated with volatile organic compounds (VOC) are avoided. It should however be noted that a large number of conventional ionic liquids are nonetheless potentially toxic and environmentally hazardous.


Environmentally friendly attributes such as biodegradability, low orders of toxicity and bioaccumulation potential and recyclability may be designed into novel ionic liquids from the outset, facilitating the production of a new generation of liquid media for clean technological applications. Bioniqs is at the forefront of such solvent engineering and has successfully developed ranges of products, based upon sustainable precursors, which fulfil the key criteria of green chemistry.

back to 'Protic Ionic Liquids'