Flotation Separation of Chalcopyrite and Molybdenite Assisted by Microencapsulation Using Ferrous and Phosphate Ions: Part II. Flotation

Ilhwan Park,Naoki Hiroyoshi,Seunggwan Hong,Mayumi Ito,Sanghee Jeon

doi:10.3390/met11030439

Abstract

Porphyry-type deposits are the major sources of copper and molybdenum, and flotation has been adopted to recover them separately. The conventional reagents used for depressing copper minerals, such as NaHS, Na2S, and Nokes reagent, have the potential to emit toxic H2S gas when pulp pH was not properly controlled. Thus, in this study the applicability of microencapsulation (ME) using ferrous and phosphate ions as an alternative process to depress the floatability of chalcopyrite was investigated. During ME treatment, the use of high concentrations of ferrous and phosphate ions together with air introduction increased the amount of FePO4 coating formed on the chalcopyrite surface, which was proportional to the degree of depression of its floatability. Although ME treatment also reduced the floatability of molybdenite, ~92% Mo could be recovered by utilizing emulsified kerosene. Flotation of chalcopyrite/molybdenite mixture confirmed that the separation efficiency was greatly improved from 10.9% to 66.8% by employing ME treatment as a conditioning process for Cu-Mo flotation separation.

Highlights

1 mM Fe2+ and 1 mM H2 PO4−, chalcopyrite was obviously coated with FePO4 ; its floatability was not affected by FePO4 coating
(46.33–49.3%) and lower Cu grade (3.8–5.2%) compared to those of untreated mixture (i.e., Mo grade, 33.8–34.6%; Cu grade, 9.6–9.8%) were obtained. These results indicate that the application of ME treatment prior to flotation of chalcopyrite/molybdenite mixture could selectively depress the floatability of chalcopyrite
This study investigated the effect of microencapsulation using Fe2+ /H2 PO4− as a pretreatment for Cu-Mo flotation separation

Summary

Introduction

Academic Editor: Man Seung Lee. Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. Porphyry-type deposits are the major sources of copper (Cu) and molybdenum (Mo)—. Approximately 60% of Cu and 50% of Mo are annually produced from these deposits [1,2,3]

Methods

Results

Conclusion