Abstract: Methylcarbonate-based ionic liquids (LIs) or carboxylates, derived from aliphatic or aromatic carboxylic acids are provided for the extraction of nitrogen compounds from hydrocarbon mixture (HCs) by liquid-liquid selective extraction, at room temperature and atmospheric pressure, where the LIs are immiscible with the HCs. This process is performed through an extraction by stifling two phases, followed by separation, or in a continuous flow system where the nitrogenous compounds are transferred to the phase formed by the LI and the total nitrogen content is substantially reduced in the HCS phase. The ionic liquids have the general formula C+A?, where: C+ is a heterocyclic organic cation, or quaternary ammonium-based; and A? is a methylcarbonate- or carboxylates-based anion, derived from aliphatic or aromatic carboxylic acids.