Abstract

To explore the influence of reagents addition sequence of the pH regulator and the starch depressant on the anionic reverse flotation of iron oxide, flotation conditional experiments were performed on mixed low-intensity and high-gradient magnetic concentrates which is the flotation feed acquired from the iron processing plant. Besides, quartz crystal micro-balance with dissipative (QCMD) was conducted to detect the adsorption phenomena of the flotation reagent on iron oxide sensors at different addition orders. The outcomes showed that the flotation performance using the pH regulator prior to the depressant was the best. For example, at 1.6 kg/Mg starch dosage, the recovery and separation efficiencies were improved by 18.3% and 21.2%, respectively, with keeping the concentrate Fe grade as high as 69.5%. Also, QCM-D frequency shifted by -41 Hz from 17 Hz to -24 Hz with increased dissipation from -2.6 x 10-6 to 8.2 x 10-6, indicating an increase in the mass of slightly rigid starch adsorption layer on the surface of iron oxide under a strong alkaline condition with adsorption density of about 0.46 mg/cm2. On the other hand, under weak alkaline conditions, starch was adsorbed, and then the starch was desorbed upon the addition of the strong alkaline solution. Whereas, adding the pH modifier to create a strong alkaline condition enhanced the starch adsorption significantly with coordination and hydrogen bonds, and prevented the following adsorption of the anionic collector for more efficient reverse flotation of iron oxide minerals.

Department(s)

Mining Engineering

Keywords and Phrases

adsorption; iron oxide; pH modifier; QCM-D; reverse flotation; starch

International Standard Serial Number (ISSN)

1643-1049

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2024 Wroclaw University of Science and Technology, All rights reserved.

Publication Date

25 Dec 2020

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