Selective Separation of Auriferous Pyrrite and Arseno-Pyrrite

The objective of the process is to separate by differential method of flotation, the pyrrite from the arseno-pyrrite, using a diagram of simple conventional flux and which can be adequated to any circuit of concentrating plant; for which we controlled the fundamental parameters which determine the mechanical behavior of the equipments of the JICA plant and cynetic of the material in studies; considering that the main valuable element of the mineral is the gold which according to mineralogical reports are found associated to the arseno-pyrrite, for which the desired product in the process is concentrated in an inverse form and in open circuit.

The development of the investigation began at first performing tests Bach type for the recognition of the material and determining the technology to be used for this specific case, election and dossification of reactives, grinding time, time of conditioning and retaining in the circuit, afterwards tests of adjustments were performed in the JICA plant and afterwards the appropriate trests were effectuated, which results are matters of present information.

Metallurgical Tests
we used in the test as a reactive collector of pyrrite the Xantato z-6, as a depressor of arseno-pyrrite the sulphur of sodium and as a foamer the pine oil; the results obtained were the desired ones observing the effective separation of pyrrite and arseno-pyrrite, the concentrate of arseno-pyrrite contains 1.35 Oz/TM of Au, 2.12 Oz/TM of Ag, 34.19% of iron and 21.26% of As with a recuperation of gold of 72.02% and 72.90%; the radius of concentration is of 2.118 or 1.

Comments
The methodology used in the execution of the tests was selected taking the criteria of concentrating the arseno-pyrrite in an inverse form of open circuit, floating the pyrrite in the rougher circuit and after in that of cleanliness.

In the test we obtained good results, the result of the arseno-pyrrite contains 1.35 Oz/TM of gold, 2.12 Oz/TM of silver, 34.19% of iron, 21,26% of arsenic with recuperation of 72.92% of Au and 72.90% of As.

We recommend effectuating an economical study to calculate the state of losses and earnings, costs and income flux, and the law of gold cuts in the head of the material which enters into the process, determining the elasticity of the project.