Flash flotation of free coarse gold using dithiophosphate and dithiocarbamate as a replacement for traditional amalgamation

Abstract

En el presente trabajo se desarrolla la flotación flash como un método alternativo a la separación gravitacional y la amalgamación con el fin de alcanzar una mayor recuperación de oro nativo grueso a través de la hidrofobicidad selectiva. Esta puede ser usada directamente en la descarga de los molinos y/o clasificadores para recuperar oro libre y grueso, cuyo tamaño sea mayor a 150 micrómetros aproximadamente. Se realizó una caracterización fisicoquímica de las superficies de oro libre a partir de las mediciones de ángulo de contacto, potencial Z (ZPC) y microscopia de fuerza atómica (AFM), y se determinó el reactivo que bajo ciertas condiciones (pH básico, sin requerimientos de un activador y un tiempo de flotación del orden de 2 minutos) logró una recuperación mayor al 90%. En este caso, el colector dialquil ditiofosfato isoamilico (AERO 3501®) fue el reactivo que presentó los mejores resultados.

Fine, coarse and fine-coarse particle flotation in mineral processing with a particular focus on the technological assessments

“…It has been broadly used but not well understood for processing complex ores containing coarse (-212+38 μm) or free gold [78]. It was designed to avoid over-grinding of the valuable dense sulfide minerals in circulating load of primary milling circuits that allows floating coarse particles with high-grades in early flotation stages [79]. Technically, flash flotation enables a concentration plant to minimize over-grinding, enhance overall recovery, increase mill throughput and improve dewatering through shrinkages filter costs and diminishes final concentrate moisture.…”

Kinetic Modelling and Optimization of Flotation Process of Electrum

“…Gold hydrophobicity is enhanced by the addition of flotation collectors such as xanthates, dithiophosphates, and mercaptobenzothiolates for its recovery. Naturally occurring or free gold is optimally recovered in a flotation circuit at natural or near-natural pulp pH values and with the addition of small amounts of the collector (Chryssoulis et al, 2009;Dunne, 2016;Bustamante-Rúa et al, 2018). Very few gold flotation plants use single collectors, in general adding the blended collector, which is a mixture of a number of collectors, is prefer to obtain better results on flotation recoveries (O'Connor et al, 1990).…”

Nickel laterite concentration through a non-conventional method with surface sulfidization

“…The wetted hydrophilic particles are depressurized and exited by the discharge of the reactor, and the hydrophobic particles adhere to the air bubbles and exit through the foam; in this way, a mineral can be separated that contains the simplest two components [17]. Unlike other methods of concentration, in flotation, it is possible to vary the difference between the material of interest and the gangue, modifying the chemical and electrochemical environment of the system by means of the appropriate selection of the added chemical reagents: collectors, foamers, activators, depressors or pH modifiers (Fig 1.) [3,[22][23][24]. The pulp is a mixture of solid particles containing mineralogical species, water, and dissolved chemical reagents, however, it must meet certain conditions, that is, that the material is properly ground no greater than 295 μ , nor less than 53 μ [9,22,23] for this specific case.…”

“…Oxide minerals have a greater affinity for oxygencontaining reactive chains, and their surface chemistry is largely determined by ion exchange reactions. Physical adsorption plays an important role together with chemical adsorption; the adsorption of the collector in non-sulfurous minerals is much less specific than in the case of sulfide minerals [3,15,17,22,24,25] This investigation studied the flotation of oxide minerals, which contain significant amounts of primary slats, such as clays and iron oxides. In addition, the same valuable minerals are generally very soft forming silts.…”