In order to decrease the solubility of PbSO4 and enhance lead recovery from PbSO4 bearing wastes, CO was employed as a reductant to transform PbSO4 into Pb S. Reaction system was established and reductive thermodynami...In order to decrease the solubility of PbSO4 and enhance lead recovery from PbSO4 bearing wastes, CO was employed as a reductant to transform PbSO4 into Pb S. Reaction system was established and reductive thermodynamics of PbSO4 was calculated by software HSC 5.0. The effects of gas concentration, reaction temperature, time and mass of sample on reduction of PbSO4 were examined by thermogravimetry(TG) and XRD. Roasting tests further verify the conclusions of thermodynamic and TG analyses. The results show that increasing temperature in the reasonable range and CO content are favorable for the formation of Pb S. The reduction process is controlled by chemical reaction and calculation value of the activation energy is 47.88 k J/mol.展开更多
The Reshian-Lamnian area within the Hazara-Kashmir syntaxis in Pakistan is composed mainly of the rocks of the Salkhala,Panjal and Murree formations.Base metal sulfide mineralization in the form of sphalerite and gale...The Reshian-Lamnian area within the Hazara-Kashmir syntaxis in Pakistan is composed mainly of the rocks of the Salkhala,Panjal and Murree formations.Base metal sulfide mineralization in the form of sphalerite and galena with lesser amounts of chalcopyrite and pyrite is present within the Salkhala Formation of the study area.Chemically all these ore phases are homogeneous in composition.The Pb isotopic composition of galena from the area suggests that there is very little or negligible variation in the ratios of 206Pb/204Pb,207Pb/204Pb and 208Pb/204Pb.Modal ages ranging from 509 to 562 Ma and the μ values of 10.71 to 10.93 have been calculated for the studied Pb-Zn mineralization.On the basis of field features,mineralogy and Pb-isotope signatures,it is concluded that the Pb-Zn sulfide mineralization in the Reshian-Lamnia area is pre-Himalayan in age and can be correlated with the Cambro-Ordovician(Pan-African) orogenic event.展开更多
Decomposition of lead sulfide concentrates in nitric acidic solutions after ferric(Ⅲ)nitrate addition and mechanical preparation has been investigated.It was found out that the decomposition can be achieved in HNO_(3...Decomposition of lead sulfide concentrates in nitric acidic solutions after ferric(Ⅲ)nitrate addition and mechanical preparation has been investigated.It was found out that the decomposition can be achieved in HNO_(3) solution(>1.5 mol·L^(-1))at the temperature above 85℃.The leaching rate of lead can be increased by means of mechanochemical activation.The use of[Fe(NO_(3))_(3)-HNO_(3)-H_(2)O]aqueous salt system allows the decomposition of lead sulfide concentrate at room temperature and in this case the concentration of HNO_(3) does not exceed 0.05-0.1 mol.L^(-1),The degree of lead recovery into solution from PbS concentrate reaches 99.3%-99.6c70 with the mechanochemical activation of this concentrate.The insoluble residues after the leaching contain SiO_(2),S^(0),FeCO_(3) and PbSO_(4).展开更多
The hexagonal liquid crystal mediated synthesis of nanostructured PbS was studied. Thioacetamide and lead acetate were used as the sulfide and lead source, respectively. It was found that the nanohole structure of PdS...The hexagonal liquid crystal mediated synthesis of nanostructured PbS was studied. Thioacetamide and lead acetate were used as the sulfide and lead source, respectively. It was found that the nanohole structure of PdS was formed in this system.展开更多
Compared with conventional method of violet spectrum, determination of the content of sulfides in fluid catalytic cracking (FCC) gasoline by using the potentiometric titration of lead tetraacetate has some advantages ...Compared with conventional method of violet spectrum, determination of the content of sulfides in fluid catalytic cracking (FCC) gasoline by using the potentiometric titration of lead tetraacetate has some advantages such as clear potentiometric abrupt change at the stoichiometric point, stable potentiometric value, exact and credible results, and simple operation. The content of sulfides in FCC gasoline of Shenghua refinery is 0.136% by this method. The standard deviation about this method is less than 0.01% and the relative standard deviation is less than 2.42%.展开更多
The numerous non-sulfide zinc ore deposits were the historical basis for the development of zinc mining in Iran.They include the Mehdiabad,Irankouh and Angouran world-class deposits,as well as the Zarigan and Haft-har...The numerous non-sulfide zinc ore deposits were the historical basis for the development of zinc mining in Iran.They include the Mehdiabad,Irankouh and Angouran world-class deposits,as well as the Zarigan and Haft-har deposits.These deposits were formed by supergene oxidation of primary sulfide minerals during the complex interplay of tectonic uplift,karst development,changes in the level of the water table,and weathering.Zn(Pb)carbonates,Zn-hydrosilicates and associated hydrated phases directly replace the primary ore bodies or fill cavities along fractures related to uplift tectonics.Direct replacement of primary sulfides is accompanied by distal precipitation of zinc non-sulfide minerals in cavities or internal sediments filling.The mineralogy of the non-sulfide mineralization in all six deposits is generally complex and consists of smithsonite,hydrozincite,and hemimorphite as the main economic minerals,accompanied by iron and manganese oxy-hydroxides and residual clays.Commonly,non-sulfide minerals in these deposits consist of two types of ore:red zinc ore(RZO),rich in Zn,Fe,Pb-(As)and white zinc ore(WZO),typically with very high zinc grades but low concentrations of iron and lead.Typical minerals of the RZO are Fe-oxyhydroxides,goethite,hematite,hemimorphite,smithsonite and/or hydrozincite and cerussite.Common minerals of the WZO are smithsonite or hydrozincite and only minor amounts of Fe-oxyhydroxides and hemimorphite.展开更多
基金Project(51204210)supported by the National Natural Science Foundation of ChinaProject(2011AA061001)supported by the National High Technology Research and Development Program of ChinaProject(2012BAC12B04)supported by the National Science and Technology Pillar Program during the Twelfth Five-Year Plan of China
文摘In order to decrease the solubility of PbSO4 and enhance lead recovery from PbSO4 bearing wastes, CO was employed as a reductant to transform PbSO4 into Pb S. Reaction system was established and reductive thermodynamics of PbSO4 was calculated by software HSC 5.0. The effects of gas concentration, reaction temperature, time and mass of sample on reduction of PbSO4 were examined by thermogravimetry(TG) and XRD. Roasting tests further verify the conclusions of thermodynamic and TG analyses. The results show that increasing temperature in the reasonable range and CO content are favorable for the formation of Pb S. The reduction process is controlled by chemical reaction and calculation value of the activation energy is 47.88 k J/mol.
文摘The Reshian-Lamnian area within the Hazara-Kashmir syntaxis in Pakistan is composed mainly of the rocks of the Salkhala,Panjal and Murree formations.Base metal sulfide mineralization in the form of sphalerite and galena with lesser amounts of chalcopyrite and pyrite is present within the Salkhala Formation of the study area.Chemically all these ore phases are homogeneous in composition.The Pb isotopic composition of galena from the area suggests that there is very little or negligible variation in the ratios of 206Pb/204Pb,207Pb/204Pb and 208Pb/204Pb.Modal ages ranging from 509 to 562 Ma and the μ values of 10.71 to 10.93 have been calculated for the studied Pb-Zn mineralization.On the basis of field features,mineralogy and Pb-isotope signatures,it is concluded that the Pb-Zn sulfide mineralization in the Reshian-Lamnia area is pre-Himalayan in age and can be correlated with the Cambro-Ordovician(Pan-African) orogenic event.
文摘Decomposition of lead sulfide concentrates in nitric acidic solutions after ferric(Ⅲ)nitrate addition and mechanical preparation has been investigated.It was found out that the decomposition can be achieved in HNO_(3) solution(>1.5 mol·L^(-1))at the temperature above 85℃.The leaching rate of lead can be increased by means of mechanochemical activation.The use of[Fe(NO_(3))_(3)-HNO_(3)-H_(2)O]aqueous salt system allows the decomposition of lead sulfide concentrate at room temperature and in this case the concentration of HNO_(3) does not exceed 0.05-0.1 mol.L^(-1),The degree of lead recovery into solution from PbS concentrate reaches 99.3%-99.6c70 with the mechanochemical activation of this concentrate.The insoluble residues after the leaching contain SiO_(2),S^(0),FeCO_(3) and PbSO_(4).
基金The authors would like to thank NNSFC ado. 29890210) and RFDP (No. 9800if8) for fund support.
文摘The hexagonal liquid crystal mediated synthesis of nanostructured PbS was studied. Thioacetamide and lead acetate were used as the sulfide and lead source, respectively. It was found that the nanohole structure of PdS was formed in this system.
基金Project of State Key Laboratory of Heavy Oil Processing (No. E030407-2).
文摘Compared with conventional method of violet spectrum, determination of the content of sulfides in fluid catalytic cracking (FCC) gasoline by using the potentiometric titration of lead tetraacetate has some advantages such as clear potentiometric abrupt change at the stoichiometric point, stable potentiometric value, exact and credible results, and simple operation. The content of sulfides in FCC gasoline of Shenghua refinery is 0.136% by this method. The standard deviation about this method is less than 0.01% and the relative standard deviation is less than 2.42%.
文摘The numerous non-sulfide zinc ore deposits were the historical basis for the development of zinc mining in Iran.They include the Mehdiabad,Irankouh and Angouran world-class deposits,as well as the Zarigan and Haft-har deposits.These deposits were formed by supergene oxidation of primary sulfide minerals during the complex interplay of tectonic uplift,karst development,changes in the level of the water table,and weathering.Zn(Pb)carbonates,Zn-hydrosilicates and associated hydrated phases directly replace the primary ore bodies or fill cavities along fractures related to uplift tectonics.Direct replacement of primary sulfides is accompanied by distal precipitation of zinc non-sulfide minerals in cavities or internal sediments filling.The mineralogy of the non-sulfide mineralization in all six deposits is generally complex and consists of smithsonite,hydrozincite,and hemimorphite as the main economic minerals,accompanied by iron and manganese oxy-hydroxides and residual clays.Commonly,non-sulfide minerals in these deposits consist of two types of ore:red zinc ore(RZO),rich in Zn,Fe,Pb-(As)and white zinc ore(WZO),typically with very high zinc grades but low concentrations of iron and lead.Typical minerals of the RZO are Fe-oxyhydroxides,goethite,hematite,hemimorphite,smithsonite and/or hydrozincite and cerussite.Common minerals of the WZO are smithsonite or hydrozincite and only minor amounts of Fe-oxyhydroxides and hemimorphite.