Abstract
The authors found out a simple and rapid analytical method of D.D.S. (dihydroxy-diphenyl sulfone) in the acidic bath for tin electrodeposition by the process of extraction and T.L.C. (thin layer chromatohraphy). The method consisted of the following 5 stages.
1) A definite volume of solution was sampled from the acidic bath.
2) D.D.S. was completely extracted from the sampled solution with ethyl acetate, and other additives in the bath were separated from D.D.S.
3) Five μl of ethyl acetate was applied on a prepared T.L. plate for T.L.C.. The T.L. plate was developed with a mixed solvent (benzene 10ml: Acetone 30ml) by ascending method. A completely separated chromatogram was obtained. The reproducible Rf values of phenol, D.D.S., and P.S.A. were 0.8, 0.6, and 0, respectively.
4) The visualization of developed T.L. plate was induced, when it was placed in a sealed chamber previously filled with iodine vapor.
A transparent glass plate was placed upon the T.L. plate to prevent its fading, and the latter plate was immediately scanned by passing through a recording densitometer.
5) The peak height of the recorded chromatogram was measured. The amount of unknown D.D.S. was calculated from an appropriate calibration curve.
