Copper ions have been widely used as activators in mineral flotation. However, in this study, it was found that copper ions can be used as auxiliary depressant for chalcopyrite depression, reversing the traditional use of copper ions as activators. In addition, a chalcopyrite depressant called sodium trithiocarbonate (Na 2 CS 3 ) has been proposed. Na 2 CS 3 was used as the main depressant and copper ions as the auxiliary depressant in this paper. Copper ions could enhance the depression effect of Na 2 CS 3 on chalcopyrite. The depression effect was reflected through micro-flotation tests, and the depression mechanisms were investigated by UV–Vis spectrophotometry determination, contact angle measurements, LEIS experiments, XPS tests, Zeta potential measurements and DFT simulation. The flotation results indicated that Na 2 CS 3 can depress chalcopyrite, and copper ions could enhance the depression effect of Na 2 CS 3 on chalcopyrite. UV–Vis spectrophotometry analysis shows that Na 2 CS 3 can reduce adsorption capacity of BX on chalcopyrite surface. Contact angle measurements and LEIS experiments indicate that hydrophilicity substance is formed after the addition of Na 2 CS 3 . XPS tests confirm that the Cu(OH) 2 produced by the addition of Na 2 CS 3 was mainly responsible for the depression. Zeta potential measurements and DFT simulation reveal the synergistic mechanism between copper ions and Na 2 CS 3 . The enhanced depression effect of copper ion is mainly achieved by promoting the desorption of BX and the formation of Cu(OH) 2 on chalcopyrite surface in the presence of Na 2 CS 3 .
Xuan Liu,Jie Gong,Kai Jiang,Xiaojuan Lai,Yu Tian,Kang Zhang
In order to reduce the apparent viscosity of lignite coal water slurries (CWSs) and improve its static stability, a series of three-arm amphiphilic block copolymers have been prepared through RAFT polymerization by using poly(ethylene glycol) methyl ether acrylate (PEGMA) and sodium 4-vinylbenzenesulfonate (SSNa) as hydrophilic monomers and styrene (St) as hydrophobic monomer. The chemical structure of the copolymers has been investigated, and the impact of relative molecular weight, hydrophilic/hydrophobic ratio, and ionic group content on the pulping performance of three-arm amphiphilic block copolymers has been examined. The lignite coal water slurries (CWSs) prepared from the block copolymer tri -P(St 50 - s -SSNa 50 ) 10K - b -PPEGMA 10K exhibit a remarkably low apparent viscosity of 395 mPa·s and excellent static stability when the coal content is at 55 wt% and dispersant content is at 0.5 wt%. Moreover, these CWSs can achieve a maximum pulping concentration of up to 59 wt%. Additionally, the thermogravimetric test reveals insights into the water occurrence in CWSs, indicating that higher levels of free water content correspond to lower apparent viscosities. Suitable hydrophobicity facilitates the removal of internal water from lignite by dispersants, disrupting its flocculation structure and promoting CWSs formation. Meanwhile, the presence of ionic groups enhances the static stability of the resulting CWSs. Furthermore, the adsorption behavior of the three-arm amphiphilic block copolymer dispersant in lignite has been analyzed through XPS testing to elucidate its dispersion mechanism. The use of three-arm amphiphilic block copolymers in preparing lignite CWSs results in lower apparent viscosity and improved static stability, attributed to the amphiphilic and steric hindrance effects of dispersants. This not only expands the application range of lignite CWSs but also highlights the significant potential of this type of dispersant.
危险品化学品经营许可证（带存储）