Cheng Chen, Liu Manman, Qiu Zhaohui, Liu Sheng, Yang Liu, Chen Wei, Liu Guangyi
College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China.
Langmuir. 2024 Oct 1;40(39):20811-20819. doi: 10.1021/acs.langmuir.4c02987. Epub 2024 Sep 20.
The flotation separation of galena from sphalerite was commonly implemented under pH > 10.5, which led to the consumption of lime. In this paper, 2-diethylamine-4-hydroxy-1,3,5-triazine-6-thiol (DEHTT) was synthesized and introduced as a highly selective collector to perform the depressant-free flotation separation of Pb/Zn sulfide minerals. The microflotation results indicated that 8.0 × 10 mol/L DEHTT recovered 94.17% galena and 26.67% sphalerite from their mixture at pH 8.5 regulated by NaCO, and under the same conditions, sodium isobutyl xanthate (SIBX) floated out 94.94% galena and 50.41% sphalerite, deducing a superior flotation selectivity of DEHTT in comparison to SIBX. AFM images displayed the more preferable adsorption of DEHTT on galena in comparison to that on sphalerite. The results of adsorption thermodynamics and kinetics inferred that the adsorption of DEHTT onto the galena surface was a spontaneous endothermic chemical process. XPS further indicated that DEHTT combined with interface Pb atoms to form the -S-Pb and -O-Pb bonds. The special affinity of DEHTT to galena achieved the selective flotation separation of galena from sphalerite without the addition of lime and depressants.
方铅矿与闪锌矿的浮选分离通常在pH>10.5的条件下进行，这导致了石灰的消耗。本文合成了2-二乙胺-4-羟基-1,3,5-三嗪-6-硫醇（DEHTT），并将其作为一种高选择性捕收剂用于实现铅/锌硫化矿的无抑制剂浮选分离。微浮选结果表明，在由NaCO调节的pH 8.5条件下，8.0×10 mol/L的DEHTT从其混合物中回收了94.17%的方铅矿和26.67%的闪锌矿，在相同条件下，异丁基黄原酸钠（SIBX）浮选回收了94.94%的方铅矿和50.41%的闪锌矿，这表明DEHTT与SIBX相比具有更好的浮选选择性。原子力显微镜（AFM）图像显示，与闪锌矿相比，DEHTT在方铅矿上的吸附更优。吸附热力学和动力学结果推断，DEHTT在方铅矿表面的吸附是一个自发的吸热化学过程。X射线光电子能谱（XPS）进一步表明，DEHTT与界面铅原子结合形成了-S-Pb和-O-Pb键。DEHTT对方铅矿的特殊亲和力实现了方铅矿与闪锌矿的选择性浮选分离，无需添加石灰和抑制剂。
