The mixing of chlorine into chrome plating bath is unavoidable in the process of decorative chrome plating.
In this paper, it is reported mainly on the absorptiometric method by nitric acid saturated with silver chromate as well as the behavior of chlorine in chrome plating solution.
In chromic acid solution, suspension is quantitatively formed by the reaction of the acid solution with Cl by adjusting the temperature and the concentration of nitric acid, and the absorbance can be measured at 800mμ with no effects of chromic acid.
A process of reducing chlorate into chloride is essential for the estimation of chlorate.
The content of chlorate is determined by the difference between the absorbance of reduced solution and that of original solution.
The above method gives a good result for the simple and rapid analysis of a small amount of chlorine in chrome plating bath.

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As it was known that Cr⁺⁶ is reduced by the reaction with cuprous cyanide, the difference of reductions between the reaction with sodium cuprous cyanide and that with cuprous cyanide powder was studied.
The above study was applied for the waste water treatment of plating shops. The waste water, consisting of the mixture of cyanide and chrome oxide, was acidified with sulfuric acid (pH=2-2.5), and then treated by aerating tower.

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Electrodeposition of lead is performed to deposit an acid-resistant coating for containers directly onto steel or cast iron. It is commonly done in fluoborate, fluosilicate and sulfamate baths.
In this study, the alkaline lead gluconate was used as a new electrolyte in lead depositing bath.
The following results were obtained.
(1) The most suitable composition of electrolyte for the best results were as follows:
2PbCo₃·Pb(OH)₂ 200g/l, (C₆H₁₁O₇)Na 100g/l, NaOH 100g/l, glue 0.2g/l, red-oil 1 drop/l
(2) The cathode current efficiency was 99% up under current density of 5A/dm² and at bath temperature of 70°C.
(3) It was shown by Hull cell method that alkaline lead gluconate bath gave higher throwing power, as compared with fluoborate or fluosilicate bath; the power was more increased when its temperature rise to 70°C or a small amount of additives such as glue and red-oil was added.

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