In the past few years, ionic liquids (ILs), surfactants and a new class of IL-derivative solvents, the deep eutectic solvents (DES), became one of the hottest research areas in chemistry, attracting scientific and industrial interest in order to develop solvents that would retain excellent technological properties while being low-cost and exerting minimal environmental effects. Given the interesting properties of surfactants and the easy adjustment of the ILs and DES chemical and physical properties through structural modification, those are promising highly specific reaction media and an innovative approach to Green Chemistry. The use of alternative solvents (ILs, DES and surfactants) is an attractive medium for various types of chemical processes, being their applications extremely varied (e. g., biocatalysis, polymer science, separation and purification processes), chiefly in aqueous biphasic systems, in order to separate and purify a large plethora of different biomolecules, from amino-acids, pharmaceutical ingredients and alkaloids to more complex chemical structures namely proteins, enzymes and antibodies. These liquid-liquid extraction systems are normally formed by the conjugation of different separation phase components and additives (i.e. salts) at certain concentrations and processing conditions. Well-known examples are the IL-salt, surfactant-salt and DES-salt combinations. However, despite the efforts made to offer a preliminary insight into the environmental behavior of alternative solvents (ILs, surfactants and DES), little is known about the environmental impact of some DES and the mixtures of these solvents, constituting a major barrier to their widespread industrial application and international registration (e.g. compliance with the EU REACH directive). Thus, the data on their (eco)toxicity, biodegradability, bioaccumulation and distribution in different environmental compartments is still missing and needs to be expanded to improve the knowledge for their prospective design as safer alternative solvents. Despite the studies published, namely by members of this research team, about data on EC50 values, regarding different environmental compartments addressing the toxicity of ILs to marine bacteria, freshwater microalgae (R. subcapitata and C. vulgaris), water column invertebrates (D. magna and D. longispina), the impact of the mixtures of alternative solvents is still practically unknown. Thus, this project proposes an integrated study on the environmental impact of ILs, surfactants and DES of industrial importance, namely various combinations of salts + ILs, ILs + surfactants, DES + salts and surfactants + salts, based on IL’ structures and IL-derivative DES synthesized-in-house. The data yielded at the end of each task can be integrated and constitute a comprehensive approach on the environmental sustainability of ILs, surfactants and DES and the mixture of these alternative solvents. We expect to produce a detailed database on the physical and chemical properties of these ILs, surfactants, DES and mixtures, and a parallel database on their aquatic ecotoxicity. These will interact to assist the development of a feasible modelling tool to predict the environmental toxicology of ILs, surfactants, DES and mixtures based on their minimal environmental effects. Finally, as the main result of the project, we intend to identify at least four environmental safe alternative solvents to efficiently separate and purify a large plethora of different biomolecules. The results of the project will be relevant from the environmental safety point of view since detailed scrutiny on the environmental risks that ILs, surfactants, DES and mixtures may pose will be carried out, and this constitutes important information for e.g. registration of newly-developed mixtures of alternative solvents.

CESAM members on this project

Ana Marta Gonçalves
Researcher

Fernando J. Mendes Gonçalves
Coordinator

Guilherme de Abreu Jeremias
Researcher

Joana Luísa Pereira
Researcher

Maria de Fátima T. Jesus
Researcher