Abstract
Needs for on-site analysis of heavy metals at low concentration have been increasing year by year. The low sensitivity of a simple visual analysis method makes it difficult to determine heavy metals at low concentration near the water quality standard value. In this study, we investigated an analysis to an industrial material eluate at ppb (μg L−1) levels using a portable quantitative analysis method that combines homogeneous liquid–liquid extraction and a smartphone. Using a chromate-treated steel containing hexavalent chromium as a model sample, an analytical performance was compared with the portable spectrophotometer. An eluate from a chromate-treated steel by heating with distilled water (10 minutes) could not be evaluated by the portable spectrophotometer, but it was confirmed that hexavalent chromium was 8 ppb in this method. The determination limit of this method was 4 ppb. Compared with the portable spectrophotometer, it was shown that this method can quantify hexavalent chromium at even low concentration and has operability suitable for on-site analysis.
