Evaluation of L-arginine as an Eco-Friendly Activator for Malachite Sulfidization Flotation

Abstract

Sulfidization xanthate flotation remains the most promising method for the beneficiation of malachite. In this study, L-arginine (LA) was first used to modify the malachite surface and improve the efficiency of sulfidization flotation. The performance of LA was evaluated by the flotation experiments. The mechanism of interaction between LA and the malachite surface was investigated by adsorption experiments, zeta potential measurements, scanning electron microscopy (SEM-EDS) and X-ray photoelectron spectroscopy (XPS) analysis. Flotation experiments showed that LA had a significantly promoting effect on malachite sulfidization flotation. Adsorption experiments and SEM-EDS results indicated that LA improved the adsorption of S (II) species into the malachite surface and promoted the formation of sulfides. This finding was further confirmed by the XPS analysis. The XPS measurements results determined that S (II) species reacted with Cu (II) on the malachite surface and form polysulfides, adding LA promoted the reaction. The zeta potential measurements showed that LA increased the positive electrical properties of the mineral surface, which was conducive to S (II) species adsorption and the sulfidization reaction. This work sheds new light on the development of sulfidization activation.

Recovery of copper from deposit of Kola Tembein, Tigray, Ethiopia

“…The XRD patterns show that the mineral has a highly crystalline structure. These properties, XRD, reveal that the ore is believed to be malachite and has his XRD pattern similar to malachite from Yunnan, China (96% pure) [8] . The XRD analysis of the sulfuric acid leaching residue showed that most of the copper was dissolved in sulfuric acid and the remaining metal oxides or gangue minerals (composed of Si, Al, Ca, Mg, and Fe, etc) were not dssolved (Table 1).…”

“…SEM images show that the surface of raw malachite particles is smooth and flat, and a few particles are found on the surface of malachite. [8] .…”

“…The most prevalent copper oxide, carbonate mineral is malachite (Cu 2 (OH) 2 CO 3 ), which has metallurgical appeal due to its 57.5% copper content [6,7] . Malachite is very soluble and extensively hydrated in sulfurization processes of dissolving in the enrichment of production of copper metal [8] . Although it is challenging to efficiently recover copper resources from these ores to meet demand, the copper leaching efficiency and recovery efficiency are about 40% and 13%, respectively [5] .…”

“…Due to its low boiling temperatures and decompositions, sulfuric acid is typically selected alternative leaching agents for oxidized copper ore [5,6] . The gangue mineral calcite, dolomite, and Fe 2 O 3 that is commonly present in malachite ores can metabolize H 2 SO 4 during the acid leaching process [8,9] .…”