resumo
Immediate naked eye distinction of methanol from ethanol can be performed by simple dissolution, in each of these solvents, of either [Na][EuFOD4] (1) complex or in mixture of products from the reaction between [P-6,P-6,P-6,P-14][Eu(FOD)(4)] and NaOPhMe3, referred as 2, ([P-6,P-6,P-6,P-14](+) = trihexyltetradecylphosphonium cation, FOD- = 1,1,1,2,2,3,3-heptafluoro-7,7-dimethyloctane-4,6-dionate). Additionally, an easy, low-cost, efficient and fast spectrofluorimetric method for the detection and quantification of methanol in mixtures with ethanol is described. This method is based on the changes in the Eu3+ luminescence in the visible region due to the interaction of the [P-6,P-6,P-6,P-14][Eu(FOD)(4)] complex with these alcohols. A limit of detection as low as 15 % (w/w) of methanol in mixtures of ethanol/methanol is discussed considering a linear calibration curve.
palavras-chave
DIRECT-INJECTION; IONIC LIQUID; QUANTIFICATION; BEVERAGES; ALCOHOL
categoria
Chemistry
autores
Leal, JP; Paz, FAA; Mendes, RF; Moreira, T; Outis, M; Laia, CAT; Monteiro, B; Pereira, CCL
nossos autores
Filipe Alexandre Almeida Paz
Investigador Principal
Ricardo Faria Mendes
Investigador Júnioragradecimentos
This work was performed under the project SunStorage - Harvesting and storage of solar energy, with reference POCI-01-0145-FEDER-016387, funded by European Regional Development Fund (ERDF), through COMPETE 2020 - Operational Programme for Competitiveness and Internationalization (OPCI), and by national funds, through FCT - Fundacao para a Ciancia e a Tecnologia I.P. This work was supported by the Associated Laboratory for Sustainable Chemistry-Clean Processes and Technologies-LAQV which is financed by national funds from FCT/MEC (UID/QUI/50006/2013) and co-financed by the ERDF under the PT2020 Partnership Agreement (POCI-01-0145-FEDER 007265) The NMR spectrometers are part of The National NMR Facility, supported by Fundacao para a Ciencia e a Tecnologia (RECI/BBB-BQB/0230/2012). Financial support from Fundacao para a Ciencia e a Tecnologia and Portugal 2020 to the Portuguese Mass Spectrometry Network (LISBOA-01-0145-FEDER402-022125) is acknowledged. This work has been supported by Fundacao para a Ciancia e a Tecnologia through the contract no IST-ID/077/2018 (Bernardo Monteiro), SFRH/BD/120985/2016 (Mani Otis) and PTDC/QEQ-QIN/3007/2014 (Tiago Moreira). C2TN/IST authors gratefully acknowledge the FCT support through the UID/Multi/04349/2013 project. Claudia C. L. Pereira thanks to Fundacao para a Ciencia e a Tecnologia, MCTES, for the Norma transitoria DL 57/2016 Program Contract.