Abstract: GZT, a new organic depressor developed by Guangxi University, was used in the laboratory and industrial tests for reducing the impurity and improving the grade of Changpo Concentrator's lead-antimony.The result proved that GZT is a very efficient selective depressor for sulfide ores.Its application in the industrial test raised the lead + antimony grade of the concentrate by 9.61 percentage points, and reduced the zinc content of the concentrate by 2.97 percentage points, raised the lead and antimony recoveries by 4.75 and 4.19 percentage points respectively, solving the problem of low grade of the lead-antimony concentrate of Changpo Concentrator.

Key words: New organic depressor GZT, Lead-antimony concentrate, Grade