To enhance the performance of traditional cationic collector,a novel polyhydroxy amine collector N-(2,3-Propanediol)-N-dodecylamine(PDDA)was designed by introducing one propylene glycol group into dodecylamine(DDA).It...To enhance the performance of traditional cationic collector,a novel polyhydroxy amine collector N-(2,3-Propanediol)-N-dodecylamine(PDDA)was designed by introducing one propylene glycol group into dodecylamine(DDA).It was prepared by a nucleophilic substitution reaction,which showed better solubility and hydrophobicity than DDA and was firstly employed as the collector for the separation of hematite and quartz.Flotation tests showed that PDDA had an excellent flotation performance and significantly better selectivity than DDA.In addition,the flotation performance and adsorption mechanism of PDDA on hematite and quartz surfaces were studied using Fourier transform infrared spectroscopy(FTIR),zeta potential and X-ray photoelectron spectroscopy(XPS)tests.These results demonstrated that the interaction between PDDA and the minerals’surfaces was mainly electrostatic adsorption and hydrogen bond,while PDDA tended to adsorb on the surfaces of quartz more than that of hematite.Performance optimization of amine collectors by introducing hydroxyl was also verified,which was of great meaning to the design,development,and application of the polyhydroxy cationic collector.In conclusion,PDDA could be used as a potential collector in the flotation separation of quartz and hematite.展开更多
In this work,the stable layer structure of serpentine,which seriously restricts the extraction of magnesium,was broken down,and a nearly 94%leaching efficiency of Mg was obtained by adding 5%fluorite powder.Compared w...In this work,the stable layer structure of serpentine,which seriously restricts the extraction of magnesium,was broken down,and a nearly 94%leaching efficiency of Mg was obtained by adding 5%fluorite powder.Compared with the system without fluorite,the Mg leaching efficiency increased by 36.42%.This result was achieved because the complexation of fluorinion(F)with Si in serpentine promoted a distorted tetrahedral orientation,which led to a loose crystal structure of serpentine and contributed to exposing more Mg for a remarkable increase in Mg recovery.It is suggested that fluorite powder could replace expensive assisted reagents in the leaching process,which would markedly decreased the cost.Moreover,an energy-efficient‘‘solvent displacement crystallization”(SDC)method was employed to efficiently recover magnesium(99.04%)from pregnant solutions.At the same time,the reuse of fluorinecontaining solutions was explored.展开更多
基金supported by the National Natural Science Foun-dation of China(Nos.52104250,51874074,and 51874073)the Liaoning Revitalization Talents Program(No.XLYC1807089)the Fundamental Research Funds for the Central Universities(Nos.N2101029 and N2101047).
文摘To enhance the performance of traditional cationic collector,a novel polyhydroxy amine collector N-(2,3-Propanediol)-N-dodecylamine(PDDA)was designed by introducing one propylene glycol group into dodecylamine(DDA).It was prepared by a nucleophilic substitution reaction,which showed better solubility and hydrophobicity than DDA and was firstly employed as the collector for the separation of hematite and quartz.Flotation tests showed that PDDA had an excellent flotation performance and significantly better selectivity than DDA.In addition,the flotation performance and adsorption mechanism of PDDA on hematite and quartz surfaces were studied using Fourier transform infrared spectroscopy(FTIR),zeta potential and X-ray photoelectron spectroscopy(XPS)tests.These results demonstrated that the interaction between PDDA and the minerals’surfaces was mainly electrostatic adsorption and hydrogen bond,while PDDA tended to adsorb on the surfaces of quartz more than that of hematite.Performance optimization of amine collectors by introducing hydroxyl was also verified,which was of great meaning to the design,development,and application of the polyhydroxy cationic collector.In conclusion,PDDA could be used as a potential collector in the flotation separation of quartz and hematite.
基金The authors gratefully thank the Fundamental Research Funds for the Central Universities(N2001018)Liaoning Revitaliza-tion Talents Program(XLYC1807089)for financial support。
文摘In this work,the stable layer structure of serpentine,which seriously restricts the extraction of magnesium,was broken down,and a nearly 94%leaching efficiency of Mg was obtained by adding 5%fluorite powder.Compared with the system without fluorite,the Mg leaching efficiency increased by 36.42%.This result was achieved because the complexation of fluorinion(F)with Si in serpentine promoted a distorted tetrahedral orientation,which led to a loose crystal structure of serpentine and contributed to exposing more Mg for a remarkable increase in Mg recovery.It is suggested that fluorite powder could replace expensive assisted reagents in the leaching process,which would markedly decreased the cost.Moreover,an energy-efficient‘‘solvent displacement crystallization”(SDC)method was employed to efficiently recover magnesium(99.04%)from pregnant solutions.At the same time,the reuse of fluorinecontaining solutions was explored.