Since the physical and chemical properties of apatite and dolomite can be similar,the separation of these two minerals is difficult.Therefore,when performing this separation using the flotation method,it is necessary ...Since the physical and chemical properties of apatite and dolomite can be similar,the separation of these two minerals is difficult.Therefore,when performing this separation using the flotation method,it is necessary to search for selective depressants.An experimental research was performed on the separation behavior of apatite and dolomite using calcium lignosulfonate as a depressant,and the mechanism by which this occurs was analyzed.The results show that calcium lignosulfonate has a depressant effect on both apatite and dolomite,but the depressant effect on dolomite is stronger at the same dosage.Mechanism analysis shows that the adsorptive capacity of calcium lignosulfonate on dolomite is higher than that of apatite,which is due to the strong reaction between calcium lignosulfonate and the Ca sites on dolomite.In addition,there is a hydrogen bond between calcium lignosulfonate and dolomite,which further prevents the adsorption of sodium oleate to dolomite,thus greatly inhibiting the flotation of dolomite.展开更多
The metallurgical properties of the CaO–SiO_(2)–Al_(2)O_(3)–4.6wt%Mg O–Fe_(2)O_(3)slag system,formed by the co-treatment process of spent automotive catalyst(SAC)and copper-bearing electroplating sludge(CBES),were...The metallurgical properties of the CaO–SiO_(2)–Al_(2)O_(3)–4.6wt%Mg O–Fe_(2)O_(3)slag system,formed by the co-treatment process of spent automotive catalyst(SAC)and copper-bearing electroplating sludge(CBES),were studied systematically in this paper.The slag structure,melting temperature,and viscous characteristics were investigated by Fourier transform infrared(FTIR)spectroscopy,Raman spectroscopy,Fact Sage calculation,and viscosity measurements.Experimental results show that the increase of Fe_(2)O_(3)content(3.8wt%–16.6wt%),the mass ratio of CaO/SiO_(2)(m(CaO)/m(SiO_(2)),0.5–1.3),and the mass ratio of SiO_(2)/Al_(2)O_(3)(m(SiO_(2))/m(Al_(2)O_(3)),1.0–5.0)can promote the depolymerization of silicate network,and the presence of a large amount of Fe_(2)O_(3)in form of tetrahedral and octahedral units ensures the charge compensation of Al^(3+)ions and makes Al_(2)O_(3)only behave as an acid oxide.Thermodynamic calculation and viscosity measurements show that with the increase of Fe_(2)O_(3)content,m(Ca O)/m(SiO_(2)),and m(SiO_(2))/m(Al_(2)O_(3)),the depolymerization of silicate network structure and low-melting-point phase transformation first occur within the slag,leading to the decrease in melting point and viscosity of the slag,while further increase causes the formation of high-melting-point phase and a resultant re-increase in viscosity and melting point.Based on experimental analysis,the preferred slag composition with low polymerization degree,viscosity,and melting point is as follows:Fe_(2)O_(3)content of 10.2wt%–13.4wt%,m(CaO)/m(SiO_(2))of 0.7–0.9 and m(SiO_(2))/m(Al_(2)O_(3))of 3.0–4.0.This work provides a theoretical support for slag design in co-smelting process of SAC and CBES.展开更多
The potential autoclave was used to study the catalytic mechanism of Cu^2+during the oxygen pressure leaching process of artificial sphalerite.By studying the potential change of the system at different temperatures a...The potential autoclave was used to study the catalytic mechanism of Cu^2+during the oxygen pressure leaching process of artificial sphalerite.By studying the potential change of the system at different temperatures and the SEM–EDS difference of the leaching residues,it was found that in the temperature range of 363–423 K,the internal Cu^2+formed a Cu S deposit on the surface of sphalerite,which hindered the leaching reaction,resulting in a zinc leaching rate of only 51.04%.When the temperature exceeds 463 K,the system potential increases steadily.The increase in temperature leads to the dissolution of the CuS,which is beneficial to the circulation catalysis of Cu^2+.At this time,the leaching rate of Zn exceeds 95%.In addition,the leaching kinetics equations at 363–423 and 423–483 K were established.The activation energy of zinc leaching at 363–423 and 423–483 K is 38.66 and 36.25 kJ/mol,respectively,and the leaching process is controlled by surface chemical reactions.展开更多
基金financially supported by the National Natural Science Foundation of China(No.52174248)the Natural Science Foundation of Jiangxi Province(No.20202ACBL214010)the Open Foundation of Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources(No.2018TP1002)。
文摘Since the physical and chemical properties of apatite and dolomite can be similar,the separation of these two minerals is difficult.Therefore,when performing this separation using the flotation method,it is necessary to search for selective depressants.An experimental research was performed on the separation behavior of apatite and dolomite using calcium lignosulfonate as a depressant,and the mechanism by which this occurs was analyzed.The results show that calcium lignosulfonate has a depressant effect on both apatite and dolomite,but the depressant effect on dolomite is stronger at the same dosage.Mechanism analysis shows that the adsorptive capacity of calcium lignosulfonate on dolomite is higher than that of apatite,which is due to the strong reaction between calcium lignosulfonate and the Ca sites on dolomite.In addition,there is a hydrogen bond between calcium lignosulfonate and dolomite,which further prevents the adsorption of sodium oleate to dolomite,thus greatly inhibiting the flotation of dolomite.
基金financially supported by the Guangzhou Basic and Applied Basic Research Project,China(No.202102020623)the Guangdong Academy of Sciences’Project of Science and Technology Development,China(No.2020 GDASYL-20200103101)+1 种基金the National Key Research and Development Program of China(No.2020YFC1908902)the Natural Science Foundation of Guangdong Province Project,China(No.2020A1515010729)。
文摘The metallurgical properties of the CaO–SiO_(2)–Al_(2)O_(3)–4.6wt%Mg O–Fe_(2)O_(3)slag system,formed by the co-treatment process of spent automotive catalyst(SAC)and copper-bearing electroplating sludge(CBES),were studied systematically in this paper.The slag structure,melting temperature,and viscous characteristics were investigated by Fourier transform infrared(FTIR)spectroscopy,Raman spectroscopy,Fact Sage calculation,and viscosity measurements.Experimental results show that the increase of Fe_(2)O_(3)content(3.8wt%–16.6wt%),the mass ratio of CaO/SiO_(2)(m(CaO)/m(SiO_(2)),0.5–1.3),and the mass ratio of SiO_(2)/Al_(2)O_(3)(m(SiO_(2))/m(Al_(2)O_(3)),1.0–5.0)can promote the depolymerization of silicate network,and the presence of a large amount of Fe_(2)O_(3)in form of tetrahedral and octahedral units ensures the charge compensation of Al^(3+)ions and makes Al_(2)O_(3)only behave as an acid oxide.Thermodynamic calculation and viscosity measurements show that with the increase of Fe_(2)O_(3)content,m(Ca O)/m(SiO_(2)),and m(SiO_(2))/m(Al_(2)O_(3)),the depolymerization of silicate network structure and low-melting-point phase transformation first occur within the slag,leading to the decrease in melting point and viscosity of the slag,while further increase causes the formation of high-melting-point phase and a resultant re-increase in viscosity and melting point.Based on experimental analysis,the preferred slag composition with low polymerization degree,viscosity,and melting point is as follows:Fe_(2)O_(3)content of 10.2wt%–13.4wt%,m(CaO)/m(SiO_(2))of 0.7–0.9 and m(SiO_(2))/m(Al_(2)O_(3))of 3.0–4.0.This work provides a theoretical support for slag design in co-smelting process of SAC and CBES.
基金financially supported by the Joint Funds of the National Natural Science Foundation of China(Nos.51804136,U1402271,51764016)Jiangxi Province Nature Science Foundation,China(No.20181BAB216017)+1 种基金Jiangxi Science and Technology Landing Project,China(No.KJLD13046)Research Fund Program of State Key Laboratory of Rare Metals Separaten and Comprehensive Utilization,Guangzhou,China(No.GK-201803)。
文摘The potential autoclave was used to study the catalytic mechanism of Cu^2+during the oxygen pressure leaching process of artificial sphalerite.By studying the potential change of the system at different temperatures and the SEM–EDS difference of the leaching residues,it was found that in the temperature range of 363–423 K,the internal Cu^2+formed a Cu S deposit on the surface of sphalerite,which hindered the leaching reaction,resulting in a zinc leaching rate of only 51.04%.When the temperature exceeds 463 K,the system potential increases steadily.The increase in temperature leads to the dissolution of the CuS,which is beneficial to the circulation catalysis of Cu^2+.At this time,the leaching rate of Zn exceeds 95%.In addition,the leaching kinetics equations at 363–423 and 423–483 K were established.The activation energy of zinc leaching at 363–423 and 423–483 K is 38.66 and 36.25 kJ/mol,respectively,and the leaching process is controlled by surface chemical reactions.
基金Projects(2020GDASYL-20200302009,2020GDASYL-20200302004,2019GDASYL-0501007)supported by Guandong Academy of Sciences,ChinaProject(2020YFC1909202)supported by Ministry of Science and Technology of China。
