Determination of surface oil on electrolytic tinplate by ultraviolet photometry
Surface oil is one of the key indexes of electrolytic tinplate products.Determination of surface oil content on electrolytic tinplate by ultraviolet photometry was established based on the study of organic extraction agent,absorption wavelength and calibration curve.N-heptane was selected as the organic solvent,and the wavelength of 270 nm was selected as absorption wavelength.The oil mass concentration was in the range of 10.00 to 100.00 mg/L,Linear relationship between values of the absorbance and the coated oil quality was obtained as shown by the linear regression equation of y=121.710 x+0.965.The proposed method was applied to the determination of surface oil in actual sample.The relative standard deviation was ‒2.81%to 2.57%,and the recovery was between 97.2%and 103.2%.Compared with gravimetric analysis,there was no significant difference.The method meets the monitoring requirements of surface oil on electrolytic tinplate production.