Saccharine solution to a toxic problem

New ionic liquids from cheap non-toxic sources.

Artificial sweeteners might be the latest answer to creating environmentally sound solvents, according to a team of US chemists.

Ionic liquids (ILs) are under widespread investigation due to their potential as ’green’ solvents. Unfortunately many of them contain fluorinated ions which reduce their appeal to the green chemistry community. Motivated by ’the continuing drive within the IL community to identify ever more benign ions for use in IL formulations’ James Davis and his colleagues in the chemistry department at the University of South Alabama have been investigating the possibility of using anions of non-nutritive sweeteners to make new ionic liquids.

They found that the anions of saccharin and acesulfame, both used widely in the food industry, could be combined with a variety of organic cations, to give room-temperature ionic liquids with melting points and viscosities comparable to those of other ionic liquids. ’Getting away from anions that are either toxic themselves, or produce other toxic materials when in use is a welcome development,’ comments Tom Welton, lecturer at Imperial College London, UK.

’The ionic liquids we’ve prepared in this fashion are in some ways quite similar to ionic liquids prepared using highly fluorinated anions, the latter being of questionable environmental and toxicological benignity’ comments Davis, and looking to the future ’one area we believe to be ripe for development is in the arena of ionic liquids that can be used without harm when introduced into a biological milieu.’

Caroline Evans