Electrospun polystyrene/Aliquat 336 for preconcentration and determination of thiocyanate in flow analysis

摘要

A new extracting polymer wool was prepared from polystyrene (PS) and the commercial extractant Aliquat 336 by electrospinning and its potential as a packing material for an online preconcentration column in an automated flow injection system was investigated for the determination of thiocyanate (SCN?). The formation of the wool fibres was confirmed by scanning electron microscopy (SEM). The polymer wool was inserted into a glass tube to prepare a column. SCN? solutions of different volumes (2-10 mL) were passed through the fibre-packed column where SCN? was extracted by the fibres. The columnwas then eluted with a small volume of 1MNaNO3 solution. The eluatewas mixed with an iron(III) solution and the resulting coloured complex (FeSCN2+) was detected colorimetrically. The system successfully achieved 21-fold preconcentration of SCN?. A linear calibration curve was obtained in the range from 0.02 to 1.0 mg L?1 SCN? with a sampling rate of 9 h?1. To the authors’ best knowledge this is the first time electrospun fibres containing a liquid extractant have been used for preconcentration in a flow analysis system.