連続水素化物発生-原子吸光法による金めっき液中の全ヒ素及びヒ素 (III) の定量分析法
1987 年 38 巻 6 号 p. 223-227
詳細
1987 年 38 巻 6 号 p. 223-227
A gold plating solution was treated with sulfuric acid, hydrogen peroxide and hydrazine sulfide, removing gold as precipitates and thoroughly reducing all arsenic to arsenic (III). Atomic absorption measurement for the samples prepared by this procedure showed that total amount of arsenic could be determined at approximately c.v. 3.0%.
The amount of arsenic (III) was determined basically by direct atomic absorption measurement. The amount of arsenic (III) in the diluted gold plating solution measured directly, however, was found to contain 8.9% arsenic (V). This suggested that the amount of arsenic (III) should be calculated by
As(III)=B-0.089A/1-0.089……(1)
A: Total amount of arsenic
B: Amount of arsenic (III) measured directly
This method of determining the amount of arsenic (III) was applied to actual gold plating solutions containing various amounts of arsenic and arsenic (III)/arsenic (V) ratios. It was confirmed that the amount of arsenic (III) in gold plating solutions could be determined at approximately c.v. 5.7%.
It was also found that the amount of arsenic codeposited in gold plating films could be determined by the same procedures as for total arsenic analysis by simply adding a step in which the film was dissolved in aqua regia.
