Mechanism of TETA in the Depression of Iron Sulphide Minerals
In the flotation of copper-nickel ores, high pyrrhotite flotation is often observed as a result of copper activation of pyrrhotite from copper species dissolved from the copper minerals present in the ores. Moreover, the flotation of pentlantide is generally similar to that of pyrrhotite making the mineral separation rather difficult.
Polyamines such as triethylenetetramine (TETA) have been used very effectively in the depression of pyrrhotite. Although TETA is known as a copper complexant, the pulp conditions where TETA is most effective are however not very well known.
In this study it was confirmed that pyrrhotite flotation with xanthate collector in alkaline pH conditions is only possible in the presence of copper species. Also, pyrrhotite flotation can be depressed with TETA addition. Infrared spectroscopy was used to measure the amount and type of xanthate present at the pyrrhotite surface while X-ray photoelectron spectroscopy and zeta potential measurement provided evidence for the removal of copper species by TETA from the pyrrhotite surface. The effect of the point of TETA addition during grinding or conditioning on pyrrhotite depression was also investigated.