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An investigation into using benzohydroxamic acid as a collector for sulfide minerals

Mohammadi-Jam Shiva, Li Ziyi, Rose Neil, Waters Kristian E.

Physicochemical Problems of Mineral Processing

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2023

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Vol. 59, iss. 5

art. no. 175662

EN

The mining industry aims to promote responsible chemical use during mineral processing operations to minimize the chemical contamination. Hydroxamic acids, which can form strong chelates with metals, have been shown to have less health and environmental issues when compared to xanthate collectors. In this work, the performance of benzohydroxamic acid (BHA) as a collector for galena, chalcopyrite, and quartz was evaluated. The minerals were conditioned with different concentrations (1.5, 3, and 4.5 kg/t) of collector at pHs 8, 9, and 10. The result showed that the treatment of the mineral surfaces with BHA enhanced the flotation recoveries of the sulfide minerals. High concentrations of benzohydroxamate anion, the protonic dissociation product of BHA, existed at basic pHs, where a chemical reaction between the anion and a metal cation on the mineral surface resulted in the adsorption of the collector onto the mineral surface. The microflotation results showed that the BHA collector was able to successfully recover galena and chalcopyrite. Their flotation recovery was dependent on the conditioning pH. Galena showed a high flotation recovery (up to 86%) at both pH 9 and 10, whereas chalcopyrite became most hydrophobic at pH values of 8 and 9 (up to 88%). None of the BHA concentrations or conditioning pHs was able to enhance quartz recovery beyond 7%. The research results have implications in the application of BHA for the froth flotation of galena and chalcopyrite.

2

Beneficial effects and mechanism of lead ion on wolframite flotation

Yang S., Qiu X., Peng T., Chang Z., Feng Q., Zhong C.

Physicochemical Problems of Mineral Processing

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2016

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Vol. 52, iss. 2

855--873

EN

In this study the effects and mechanism of lead ions influence on wolframite flotation with benzohydroxamic acid (BHA) were studied through micro-flotation, adsorption experiments, zeta potential measurements, logarithmic concentration diagram, and X-ray photoelectron spectroscopy. It was observed that lead ions could significantly enhance the recovery of wolframite in flotation and adsorption density of collector BHA onto the wolframite surface. The results showed that Pb existed in the forms of lead ion, monohydric lead, and lead hydroxide at the water-wolframite interface respectively, at three pH ranges. They increased the zeta potential of wolframite. However, the zeta potential of wolframite was still negative, resulting in repulsive electrostatic force to anionic collector BHA. Combining with XPS spectra, it revealed the chemisorption of BHA onto the wolframite surface. In addition, PbO or Pb(OH)2 was observed on the wolframite surface due to the reaction between lead ions and wolframite. These reaction products increased the adsorption site of BHA on the wolframite surface because Pb-hydroxamate was found on the wolframite surface.

3

Relationship between flotation and Fe/Mn ratio of wolframite with benzohydroxamic acid and sodium oleate as collectors

Yang S., Feng Q., Qiu X., Gao Y., Xie Z.

Physicochemical Problems of Mineral Processing

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2014

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Vol. 50, iss. 2

747--758

EN

Several studies revealed that flotation of wolframite changes with different Fe/Mn ratios, but they did not reach a consensus. This relationship in the presence of benzohydroxamic acid (BHA) and sodium oleate (NaOl) as collectors was studied in this paper through comparison of probability distribution curve of wolframite with different Fe/Mn ratios between the raw ore and the flotation concentrate, the pure mineral flotation and solution chemistry of flotation. The results showed that wolframite with high Fe/Mn ratio showed higher flotation with BHA as a collector while the flotation behavior of wolframite was completely opposite with NaOl as a collector. Besides, the calculations of chemical equilibrium in the solution were plotted as ΔG°-pH graphs. The results revealed that the flotation of wolframite may be determined by the interaction between BHA and ferric(II) ion or between NaOl and manganous ion. From the perspective of collector mixture, the results also explain the high collecting capability of the BHA/NaOl collector mixture, which can be defined as “functional complementation”.