Deep eutectic solvent-based extraction of metals from oil samples for elemental analysis by ICP-OES

• Published in: Microchemical journal 2022-08, Vol.179, p.107456, Article 107456
• Main Authors: Shishov, Andrey, Savinov, Sergey, Volodina, Natalia, Gurev, Ivan, Bulatov, Andrey
• Format: Article
• Language: English
• Subjects: Deep eutectic solvent; Elemental analysis; Extraction; Inductively coupled plasma; Motor oil; Vegetable oil
• ISSN: 0026-265X; 1095-9149
• DOI: 10.1016/j.microc.2022.107456

[Display omitted] •Effect of deep eutectic solvents (DESs) precursors on metals separation from oil matrices.•Hydrogen bond donors of DESs were arranged according to metals extraction efficiency.•DESs based on carboxylic acids as effective extractants for elemental extraction from oils.•Determination of metals in oil samples by ICP-OES without microwave digestion. In this work deep eutectic solvents based on choline chloride and different hydrogen bond donors were systematically investigated for separation of singly- and multiply-charged metals (Ag, Al, B, Ba, Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, Pb, Sn, Ti, V and Zn) from oil matrices. The effect of deep eutectic solvents precursors was shown to play a critical role in the extraction of different metals. Carboxylic acids, polyols, sugars, urea, and its derivatives were studied as hydrogen bond donors of deep eutectic solvents for metals separation. It was found that deep eutectic solvents based on carboxylic acids and sugars provided the highest extraction efficiency in the extraction of both singly- and multiply-charged metals from oil matrices. Moreover, the effect of water as precursor of deep eutectic solvent on metals’ separation was investigated. Among studied solvents, the deep eutectic solvent containing choline chloride, lactic acid and water provided the highest extraction recovery (up to 99 %). The extraction solvent was applied to elemental analysis of oil samples (vegetable oil and motor oil) by ICP-OES method. Under optimal conditions, the limits of detection were in the range 0.02 to 17 mg kg−1. The developed procedure is not required a microwave digestion of oil samples for elemental analysis.