Hot shortness caused by sulfur

What are the best ways to reduce the sulfur content in molten copper? At times we experience hot shortness in the cast bar (SCR system) from elevatied sulfur which ranges from 10-20 ppm.

Is there an effective way to reduce the sulfur content OR a way to minimize the deleterious effects?

Thanks,
Chris Tucker

Dear Mr.Chris:

I think that you bought Cathode obtained by ELECTROWINNING, you can know it because the cathode obtined by this method has few quantity of Ag (1-2 ppm) comparing with the ELECTROREFINING. In my experience, you will not have any problem if you work with cathodes with a content of sulfur below 5-6 ppm. Now your only solution is mixing the bad cathodes with other with less sulfur (dilute it).

I did homologations of the followings brands

Sulfur content:

1.- Las Cruces : 1-2 ppm
2.- BHP: S: 3 ppm
3.- Hindalco: 3-3.5 ppm
4.- CODELCO: 4.6 ppm

A good book that you ought to buy is:

SAMPLING AND ANALYSIS OF COPPER CATHODES (Tuddenham/Hibbeln, editors).

Best Regards,

Juan Carlos del Rey Menéndez