In this paper, a novel collector dihexyl (2-(hydroxyamino)-2-oxoethyl) phosphonate (DHHAOEP) was synthesized and used as a flotation collector to separate scheelite from quartz. Micro-flotation experiments demonstrated that DHHAOEP can effectively separate scheelite from quartz within a pH range of 6–9. Artificial mixed ores flotation experiments revealed that at a pH of approximately 8 and a DHHAOEP concentration of 8 × 10⁻⁵ mol/L, the flotation recovery of scheelite reached 73% with a grade of 54%. The contact angle and Zeta potential measurements showed that the addition of DHHAOEP caused a positive shift in the zeta potential and enhanced the surface hydrophobicity of scheelite. The FTIR, XPS, and DFT analyses further elucidated that DHHAOEP anchored on the scheelite surface through the bonding reaction between its -C(=O)-NHOH moiety and WO₄²⁻ or Ca active sites on the scheelite surface, forming a five-membered ring. Meanwhile, the existence of the P=O group makes the distance between oxygen atoms in -C(=O)-NHOH very close to that in WO₄²⁺, which is beneficial to the reaction. The present work aims to develop a novel flotation collector with multi-functional groups to enhance scheelite recovery efficiency and selectivity.

Camellia oleifera Abel. (C. oleifera) ranks among the four major woody oil crops globally. It is widely cultivated in the subtropical regions of southern China (Yang et al. 2025). China has the wor...

Herein, diacylglycerol (DAG) was prepared from Swida wilsoniana fruit oil by a two-step enzymatic process, and the quality of crude Swida wilsoniana fruit oil (Crude oil), refined Swida wilsoniana fruit oil (Refined oil), DAG oil derived from crude oil (Crude oil-DAG), and DAG oil derived from refined oil (Refined oil-DAG) were compared and evaluated. The results showed that Lipozyme® RM IM enzyme exhibited the best hydrolysis effect in the hydrolysis reaction, while Novozym® 435 enzyme had a lower reaction energy barrier and a faster esterification catalytic rate in the esterification reaction, yielding a DAG content of up to 72.99%. Quality analysis showed that the physical and chemical indicators of the four oils all met the national standards, refining and enzymatic reactions can affect the tocopherol content, oxidative stability and flavor components of oils. The tocopherol content and oxidative stability in the crude oil were the best, and the volatile flavor substances of the crude oil and its DAG were richer. The research confirmed that the crude Swida wilsoniana fruit oil is an ideal raw material for the preparation of DAG, and the obtained DAG has excellent comprehensive quality.

Sphalerite–pyrite separation has always been one of the key issues of concern in the field of mineral flotation. To achieve selective flotation separation of sphalerite and pyrite, a novel flotation system, FeSO₄+NaH₂PO₄-CuSO₄-SIBX, was adopted. This study validated the novel separation system using mineral flotation experiments. The changes in the hydrophobicity and surface charge of the minerals were evaluated using experiments such as contact angle, zeta potential, and agglomeration. Finally, the mechanism of sphalerite–pyrite separation was revealed through XPS and solution chemistry analysis. The results showed that sphalerite and pyrite were effectively separated by flotation. In the novel flotation system, the synergistic effect of FeSO₄ and NaH₂PO₄ shifted the surface potential of pyrite positively, and subsequent treatment with CuSO₄ and SIBX did not significantly alter its hydrophobicity. However, sphalerite, after treatment with FeSO₄+NaH₂PO₄-CuSO₄-SIBX, exhibited significantly enhanced hydrophobicity and marked mineral particle agglomeration. Further research revealed that within the pH range of 6.0–8.0, hydrophilic components formed by Fe²⁺ and H₂PO₄⁻ (e.g., Fe(H₂PO₄)⁺ and Fe₃(PO₄)₂·8H₂O) selectively adsorbed onto the pyrite surface, enhancing its hydrophilicity. Meanwhile, sphalerite was activated by the substitution reaction of Cu²⁺ with ZnS, forming a hydrophobic layer on its surface with SIBX in the slurry.