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Application of dodecyl amine/dodium petroleum sulfonate mixed collector in quartz-feldspar flotation separation

He Yuhao, Ren Zijie, Zhu Huimin, Zheng Renjun, Li Mingyang, Song Yuhan, Chen Zhijie

Physicochemical Problems of Mineral Processing

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2024

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Vol. 60, iss. 1

art. no. 185553

EN

It’s highly challenging to separate feldspar from quartz by flotation owing to their similar crystal structure and physicochemical properties. Using mixed collectors has become a promising method to improve the quartz-feldspar separation. In this study, mixed dodecyl amine (DDA) and sodium petroleum sulfonate (SPS) surfactants were used in the flotation separation of feldspar and quartz, and the adsorption mechanism of mixed collectors and depression mechanisms of two depressants were investigated through zeta potential, contact angle and Fourier transform infrared (FT-IR) spectra. When the pH reached 4.5, the separation of feldspar from quartz was more obvious. In the presence of DDA/SPS collector, the contact angle of feldspar was increased more obviously leading to enhance hydrophobicity. The infrared spectra revealed the interaction of collectors on feldspar surface involved physical and chemical adsorption, whereas the adsorption of collector on quartz was only physical interactions. The use of sodium hexametaphosphate resulted in a significantly enhanced separation performance. The weaker physical adsorption of mixed collector on quartz can be destroyed by sodium hexametaphosphate. This study is beneficial for understanding the collect mechanisms of mixed cationic-anionic surfactants on quartz and feldspar minerals, and promotes the development of advanced feldspar separation techniques.

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Preparation of amphoteric modified bentonite from calcium-based bentonite for adsorption of anionic dye. The importance of sodium-modification pretreatment

Yin Hang, Ren Zijie, Gao Huimin, Han Weiyi, Guan Junfang

Physicochemical Problems of Mineral Processing

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2021

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Vol. 57, iss. 1

1--17

EN

To understand the influence of sodium-modification pretreatment on the adsorption of anionic dye by amphoteric modified bentonite, three kinds of adsorbent materials, including sodium-modified bentonite, amphoteric modified calcium-based bentonite and amphoteric modified bentonite pretreated by sodium modification, were firstly synthesized and characterized, and afterwards their adsorption performance and mechanism for a form of anionic dye, Acid Yellow 11, were investigated comparatively. The crystalline phases, hydration property, surface charge characteristic and functional groups of prepared modified bentonite were characterized and evaluated by X-ray diffraction swelling volume, Zeta potential and Fourier transform infrared spectroscopy, respectively. The sodium modification expanded the interlayer space of montmorillonite, released the internal surface area and improved the hydration performance of bentonite. Due to the replacement of Na+ for Ca2+, the probability of interlayer cations overflowing from the interlayer space and exchanging with the amphoteric modifier increases. Therefore, the content of interlaminar organic material in amphoteric modified bentonite pretreated with sodium-modification pretreatment was higher than that in unpretreated amphoteric modified bentonite. The hydration and dispersibility were significantly stronger, and the adsorption capacity of acid dye was also better. The findings of this investigation suggest that sodium modification pretreatment is very positive and necessary in the process from sodium–amphoteric modification.

3

Application of mixed collectors on quartz-feldspar by fluorine-free flotation separation and their interaction mechanism : a review

Li Peiyue, Ren Zijie, Xie Enjun, Duan Shutong, Gao Huimin, Wu Jianxin, He Yuhao

Physicochemical Problems of Mineral Processing

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2021

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Vol. 57, iss. 4

139--156

EN

Quartz and feldspar are usually exist in symbiosis in nature, and they are difficult to be separated effectively by conventional physical methods owing to their similarities in crystal structures and surface characteristics. Flotation is the most resultful method, and especially, flotation with hydrofluoric acid (HF) is the most efficient way. Because HF may cause serious environmental and health problems, the effective and environmentally friendly separation of quartz and feldspar remains a formidable challenge. The crystal structure, surface broken bonds, surface energy, and solid–liquid interface properties of quartz and feldspar are investigated in this paper. In particular, some types of mixed cationic/anion collectors and their interaction mechanism on the quartz and feldspar surfaces with acidic, alkaline, and neutral media in the absence of fluorine are discussed, and the grade and scheme of quartz and feldspar for the practical application are illustrated. This review proposes concrete research approaches and provides perspectives for the advanced processing of quartz and feldspar in an environmentally friendly and economical way.