The efficient separation of scheelite from calcium-bearing minerals, especially calcite, remains a challenge in practice. In this work, a novel reagent scheme incorporating a depressant of sodium hexametaphosphate (SHMP) and a collector mixture of octyl hydroxamic acid (HXMA-8) and sodium oleate (NaOl) was employed in both single and mixed binary mineral flotation, and it proved to be highly effective for the separation. Furthermore, the role of the pH value in the separation was evaluated. Additionally, the mechanism of the selective separation was investigated systemically via zeta potential measurements, fourier transform infrared (FTIR) spectroscopy analysis, X-ray photoelectron (XPS) spectroscopy analysis and crystal chemistry calculations. It turns out that the selective chemisorption of SHMP on calcite (in the form of complexation between H2PO4−/HPO42− and Ca2+) over scheelite is ascribed to the stronger reactivity and higher density of Ca ions on the commonly exposed surfaces of calcite minerals. The intense adsorption of HXMA-8 on scheelite over calcite due to the match of the O O distances in WO42− of scheelite and CONHOH of HXMA-8 holds the key to the successful separation. We were also interested in warranting the previous claim that NaOl is readily adsorbed on both minerals via chemisorption. Our results provided valuable insights into the application of mixed collectors and an effective depressant for flotation separation.

Adsorption of a novel reagent scheme on scheelite and calcite causing an effective flotation separation.

Froth flotation of scheelite has regained new focus since the 2010s and research regarding floatability and reagents has made great progress over the years. The main objective was and remains the selective flotation of scheelite from other calcium-bearing minerals, in particular calcite, fluorite and apatite. Due to similar properties, most attempts have limited success or only specific application (linked to a type of ore or a location). This article aims at reviewing all general physical-chemical information on froth flotation of scheelite, including electrokinetic properties, influence of pH and already existing reagents as well as ones still under examination. It appears that chelating or mixed collectors and modified versions of sodium silicate and quebracho hold great promise for scheelite flotation, while the use of said depressants and/or promoters seems inevitable.

Froth flotation of scheelite – A review

Fatty acid flotation versus BHA flotation of tungsten minerals and their performance in flotation practice

The effect of sodium alginate on the flotation separation of scheelite from calcite and fluorite

Selective flotation of scheelite from calcite: A novel reagent scheme

The flotation separation of scheelite from calcite using acidified sodium silicate as depressant

With the development of aluminium industry,the red mud environmental protection problem appears especially urgent.The main body of a book brief judge the fundamental character having stated the red mud,the red mud research in the field of comprehensive utilization progresses,comprehensive utilization method and the treatment reclaiming the analysis having been in progress,looking forward to being red mud find and new approach to red mud.

The Red Mud Reclaims Synthetically and Makes use of Current Situation and Progress

In this study the collecting power of N-oleoyl sarcosine acid towards wolframite and quartz was studied using flotation. The adsorption mechanism was also discussed based on the results from adsorption experiments, zeta potential measurements and infrared spectroscopy study. The flotation results showed that N-oleoyl sarcosine acid showed a good collecting power towards wolframite, and the optimal flotation pH = 7 was obtained. However, the collecting power of N-oleoyl sarcosine acid towards quartz was weak. Therefore, the flotation separation of wolframite from quartz can be performed using Noleoyl sarcosine acid as a collector. The adsorption tests and electrokinetic studies showed that N-oleoyl sarcosine acid adsorbed only on the wolframite surface. Additionally, the results from the infrared spectroscopy study confirmed that N-oleoyl sarcosine acid is adsorbed on the wolframite surface, and the metal complex (ferriccarboxylate) maybe the major adsorbed species.

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Flotation separation of wolframite from quartz using N-oleoyl sarcosine acid as collector

Activation mechanism of calcium hydrolysate on the spodumene surface and its effect on the adsorption of collector

In order to increase the absorption capacity of Zeolite of NH4+-N, clinoptilolite from Henan Gongyi was modified, and the modified zeolite concentration was 50 mg·L-1 imulated NH4+-N wastewater modified after the use of roasting by static test, microwave, acid, salt, and integrated heat, the result of experiments was that the Zeolite adsorption of Natural Zeolite and six modified zeolite adsorption were respectively 2.1 mg·g-1, 2.58mg·g-1, 2.53 mg·g-1, 2.84 mg·g-1, 2.86 mg·g-1, 2.95 mg·g-1, 3.03 mg·g-1, The use of scanning electron microscopy (SEM), X-ray diffraction (XRD) and infrared absorption spectrometry(IR) analysis of changes with and without modification, howing that the modification helped to improve the adsorption capacity of zeolite of ammonia-nitrogen, The results show that increasing porosity zeolite pore more open and comprehensive modification shows the best effect.

http://ieeexplore.ieee.org/iel5/5765754/5774181/05774215.pdf

Luo Xian-ping

Papers

The flotation separation of scheelite from calcite using acidified sodium silicate as depressant

The Red Mud Reclaims Synthetically and Makes use of Current Situation and Progress

Flotation separation of wolframite from quartz using N-oleoyl sarcosine acid as collector

Activation mechanism of calcium hydrolysate on the spodumene surface and its effect on the adsorption of collector

Notice of Retraction Experimental study on different modified Zeolite's absorption of NH 4 + -N