Choline [Amino Acid] Ionic Liquid/Water Mixtures: A Triple Effect for the Degradation of an Organophosphorus Pesticide

FIGUEROA, ROBERTO; FALCONE, R. DARÍO; MEDINA, MAYTE; TAPIA, RICARDO A.; PAVEZ, PAULINA; MILLÁN, DANIELA

ACS Omega

ACS

Año: 2020 vol. 5 p. 26562 - 26572

2470-1343

A series of ionic liquids (ILs) composed by choline(Ch) as a cation and different amino acids (AA) as anions and theirrespective aqueous mixtures were prepared using different[Ch][AA] contents in a range of 0.4−46 mol % IL. These solventswere used for the first time to achieve an eco-friendlier Paraoxondegradation. The results show that [Ch][AA]/water mixtures arean effective reaction medium to degrade Paraoxon, even when theIL content in the mixture is low (0.4 mol % IL) and without theneed of an extra nucleophile. Both the kinetics and the degradationpathways of pesticides depend on the nature of the AA on[Ch][AA] and the amount of an IL present in the mixture. We have demonstrated that in those mixtures with a low amount of[Ch][AA], the hydrolysis reaction is the main pathway for Paraoxon degradation, showing a catalytic effect of the IL. However, asthe percentage of [Ch][AA] increases in the mixture, the nucleophilic attack of [Ch][AA] is evident. Finally, the aim of this studywas to provide evidence of a promising and biocompatible methodology to degrade a toxic compound (Paraoxon) using a minimalquantity of an IL designed totally from natural resources.