Flotation of non-ferrous metals from arsenopyrite ore

Arsenic pyrite is a composite ore that contains both non-ferrous and precious metals. With the addition of such ore processing capacity, there is an urgent need to make a choice, either to discard arsenic and tailings together, or to separate it into arsenic products and mixed products.
The content of scattered non-ferrous metals in arsenopyrite ore ranges from 0.01% to 0.15%. In this type of ore, gold is mainly associated with sulfides in a colloidal low dispersion state, while silver exists as sulfonates. Unlike gold, non-ferrous metal sleeve and silver do not always coexist with arsenic. When using chemical methods to treat this ore in the gold mining section, the sulfonate enters the tailings into silver, and even non-ferrous metals are lost.
The significant mineralogical and technological characteristics of arsenopyrite determine that it is necessary to concentrate the dispersed non-ferrous metals and silver in the lowest arsenic containing individual products produced by pyrometallurgical smelting using preferential flotation method, followed by flotation of the gold arsenic ore deposit into the concentrate.
The main mineral deposits include arsenopyrite, chalcopyrite, and iron sulfur arsenic cobalt ore. Bismuth ore. The ore is characterized by a high degree of symbiosis between non-ferrous and precious metals and arsenopyrite. In order to separate the various mineral deposits as much as possible, the ore is ground to a particle size of 96% -0.074 millimeters.
Flotation uses base acids as collectors to separate non-ferrous metals from arsenic. The selection of aliphatic and aromatic acids in the flotation process can separate non-ferrous metal enclosure from precious metals, which form essentially arsenic free complexes with base acids
The comparison of some basic acids (in the form of sodium salt), succinic acid, basic acetic acid, phosphoric acid, meta acid and the effect on acid shows that phosphoric acid (2-acid) is the most useful collector, which can ensure a high metal recovery rate in foam products.
Cobalt and gold associated with arsenic are recovered from arsenopyrite concentrate using potassium butyl xanthate.
Free nonferrous metals and precious metals are enriched into foam products by ortho acid, and the yield is 1.5%~2.0%. In the first flotation concentrate, the grades of copper, bismuth, and silver reached 3.11%, 4.40%, and 100 g/ton respectively, with recoveries of 97%, 80%, 78.10%, and 80.4%. The arsenic recovery rate in this product was 5%, indicating that it is necessary to rely on flotation to select the connected arsenic pyrite.
When only butyl xanthate is used in a mixed flotation of the ore, the grades of copper, bismuth, and cobalt in the mixed concentrate are 0.8%, 0.3%, and 0.95% respectively. At this moment, the arsenic content reaches 35%. The second foam product is arsenopyrite concentrate, with arsenic recovery rate of 92% and grade of 22%~23%.
Based on the material introduction analysis obtained, a two-stage flotation process using two collectors can be recommended for arsenic pyrite type ores with high arsenic content. The use of base acids in the flotation process can ensure a certain recovery rate of free non-ferrous and precious metals. The use of xanthate can assist in enriching arsenic pyrite, pyrite, and their associated metals.