Gold potassium lemon acid for gold plating and method for producing the same

Abstract

The invention discloses citric acid gold potassium used for gold plating and the preparation method thereof. The molecular formular of the citric acid gold potassium is K3Au2C9H5O7N2. The method comprises the steps as follows: gold trichloride is dissolved in water of certain temperature, is concentrated and diluted under the temperature for multiple times, and is reacted with potassium citrate, ethylene diamine tetraacetic acid and malononitrile in a reactor under the certain temperature and the certain time to produce the organic gold salt which has low toxicity and contains no free cyanogen. When the product has the same gold content with the potassium gold cyanide, the total CN- is 5 to 6 percent, being 50 percent lower than that of the CN- in the potassium gold cyanide. The waste liquid after gold plating contains free the CN- in small amount. The invention reduces the cost of waste water treatment for the electroplating plants.

Description

technical field

[0001] The invention relates to a gold citrate salt for gold plating, in particular to a preparation method of gold potassium citrate for gold plating, which belongs to the field of chemical technology. Background technique

[0002] In the gold plating industry, because potassium cyanide has a strong complexing force on gold ions, most enterprises in my country choose inorganic electroplating gold salt——potassium aurous cyanide as the main salt of gold plating during electroplating. The corrosion resistance of the workpiece and the characteristics of the coating and the plated parts are then formulated with an acidic gold plating or alkaline gold plating solution to meet the requirements of the process conditions.

[0003] National Defense Industry Press published the first edition in June 1990, and the book "Practical Electroplating Process" edited by Li Hongnian, Zhang Shaogong, Zhang Bingqian, Song Ziyu, etc., which was printed for the second time in Novemb...