Title: Technological process for reduction of gastric-juice-soluble cadmium in cadmium pigment
Application Number: 90105597 Application Date: 1990.11.15
Publication Number: 1061422 Publication Date: 1992.05.27
Approval Pub. Date: Granted Pub. Date:
International Classifi-cation: C09C1/10
Applicant(s) Name: Chemical Engineering Research Address: 411100
Inventor(s) Name: Dai Lixin, Liu Junsheng
Attorney & Agent:
Abstract:
     This invention relates to a process for reducing gastric juice soluble cadmium in cadmium pipments (such as pure cadmium pigment, lithopone-type cadmium pigment. Kaoline-type cadmium pigment). Its aim is to reduce the amount of cadmium soluble in 0.07 mole per liter of hydrochloric acid solution of cadmium pigment to a quantity lower than 0.1 percent. Its feature is that the slurry of cadmium pigment resulted by calcination and wet milling is formed into suspension by addition of water, the acidity of this suspension is adjusted to a definite range of pH valve by adding acid solution with a definite concentration to dissolve the soluble cadmium in cadmium pigment. The pigment in suspension is rinsed several times with water and the suspension is adjusted to a condition closing to neutral value, filtered, dried, and pulverized to obtain the product. The cadmium ions in rinsing water is reacted with osdium carbonate in waste liguor for synthesizing raw material to form a precipitate.....
Time: 9
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