The leaching kinetics of low grade zinc oxide ore in NH3-NH4Cl-H2O system was studied. The effects of ore particle size, reaction temperature and the sum concentration of ammonium ion and ammonia on the leaching effic...The leaching kinetics of low grade zinc oxide ore in NH3-NH4Cl-H2O system was studied. The effects of ore particle size, reaction temperature and the sum concentration of ammonium ion and ammonia on the leaching efficiency of zinc were examined. The leaching kinetics of low-grade zinc oxide ore in NH3-NH4Cl-H2O system follows the kinetic law of shrinking-core model. The results show that diffusion through the inert particle pores is the leaching kinetics rate controlling step. The calculated apparent activation energy of the process is about 7.057 kJ/mol. The leaching efficiency of zinc is 92.1% under the conditions of ore particle size of 69 μm, holding at 80 ℃ for 60 min, sum ammonia concentration of 7.5 mol/L, the molar ratio of ammonium to ammonia being 2-1, and the ratio (g/mL) of solid to liquid being 1-10.展开更多
The effects of alkali oxides （Na2O and K2O addition on both the sintering behavior and dielectric properties of Ca-AI-B-Si-O glass/Al2O3 composites were investigated by Fourier transform infrared spectroscopy （FTIR...The effects of alkali oxides （Na2O and K2O addition on both the sintering behavior and dielectric properties of Ca-AI-B-Si-O glass/Al2O3 composites were investigated by Fourier transform infrared spectroscopy （FTIR）, differential scanning calorimeter （DSC）, X-ray diffractometry （XRD） and scanning electron microscopy （SEM）. The results show that the increasing amount of alkali oxides in the glass causes the decrease of [SiO4], which results in the decrease of the continuity of glass network, and leads to the decrease of the softening temperature Tf of the samples and the increasing trend of crystallization. And that deduces corresponding rise of densification, dielectric constant, dielectric loss of the low temperature co-fired ceramic （LTCC） materials and the decrease of its thermal conductivity. By contrast, the borosilicate glass/A1203 composites with 1.5% （mass fraction） alkali oxides sintered at 875 ℃ for 30 rain exhibit better properties of a bulk density of 2.79 g/cm3, a porosity of 0.48%, a 2 value of 2.28 W/（m.K）, a er value of 7.82 and a tand value of 9.1 × 10-4 （measured at 10 MHz）.展开更多
NiO-La0.3Ce0.7O2-δ(LDC30) novel anode was investigated for IT-SOFCs(Intermediate Temperature-Solid Oxide Fuel Cells) with LaGaO3-based electrolyte. The results showed that LDC30 has a suitable chemical compatibility ...NiO-La0.3Ce0.7O2-δ(LDC30) novel anode was investigated for IT-SOFCs(Intermediate Temperature-Solid Oxide Fuel Cells) with LaGaO3-based electrolyte. The results showed that LDC30 has a suitable chemical compatibility with NiO and NiO-LDC30 has a good thermal expansion matching with LDC30 interlayer and LSGM(La0.8Sr0.2Ga0.8Mg0.2O3-δ) electrolyte, so NiO-LDC30/LDC30 was considered as a feasible and novel anode system. It was also shown that NiO content plays a key role on polarization performance and morphology of the anode. When the content of NiO was 60%(mass fraction), the polarization loss of anode was the lowest. Next we will optimize the porosity and sintering procedure to modify the microstructure and performance of the anode.展开更多
ZHOU Bai-Bin *,1,2 WEI Yong-De 1 LI Zhong-Hua 1 ( 1 Department of Applied Chemistry,Ha rbin Institute of Technology ￡?Harbin￡±￡ì￡°￡°￡°￡±￡(c)( 2 Department of Chemistry,Harbin Norm...ZHOU Bai-Bin *,1,2 WEI Yong-De 1 LI Zhong-Hua 1 ( 1 Department of Applied Chemistry,Ha rbin Institute of Technology ￡?Harbin￡±￡ì￡°￡°￡°￡±￡(c)( 2 Department of Chemistry,Harbin Normal University￡?Harbin￡±￡ì￡°￡°￡?￡°￡(c) The air-solid interface reaction of Ce,Lu with K10 H 3[Gd (SiMo 4 W￡*O￡3￡1￡(c) 2]through chemistry-heated permeation is reported for the fi rst time￡(r)The permeated complex is characterized by ICP and the result shows tha t the mini mum Ce,Lu can permeate into the inner sph ere of K 10 H ￡3 ￡?Gd ￡¨SiMo ￡′ W ￡* O ￡3￡1 ￡(c) 2]The IR ,XRD patterns give the eviden ce that after permeation the comple x still keeps the Keggin structure,howe ver,its crystal structure is different from the complex before permeation￡(r)The cond uctivity of the permeated complex has been measured with the four-electr ode method and the data show that the co nductivity of the complex after permeation is 10 6 times higher than that of the sample before permeation and reaches ￡′￡(r)84 6×10 -1 S·cm -1 ￡(r)These indicate that the permeated c omplex is a good solid electrolyte and further appli cations are also expected￡(r)展开更多
基金Project(2007CB613604) supported by the Major State Basic Research Development Program of ChinaProject(50674104) supported by the National Natural Science Foundation of ChinaProject(GJJ08279) supported by the Department of Education of Jiangxi Province
文摘The leaching kinetics of low grade zinc oxide ore in NH3-NH4Cl-H2O system was studied. The effects of ore particle size, reaction temperature and the sum concentration of ammonium ion and ammonia on the leaching efficiency of zinc were examined. The leaching kinetics of low-grade zinc oxide ore in NH3-NH4Cl-H2O system follows the kinetic law of shrinking-core model. The results show that diffusion through the inert particle pores is the leaching kinetics rate controlling step. The calculated apparent activation energy of the process is about 7.057 kJ/mol. The leaching efficiency of zinc is 92.1% under the conditions of ore particle size of 69 μm, holding at 80 ℃ for 60 min, sum ammonia concentration of 7.5 mol/L, the molar ratio of ammonium to ammonia being 2-1, and the ratio (g/mL) of solid to liquid being 1-10.
基金Project(2007AA03Z0455) supported by the National High Technology Research and Development Program ("863" Program) of ChinaProject(BE2010194) supported by Science & Technology Pillar Program of Jiangsu in China+3 种基金Project(BE2009168) supported by Science & Technology Pillar Program of Jiangsu in ChinaProject supported by the Priority Academic Program Development (PAPD) of Jiangsu Higher Education InstitutionsProject(KF201103) supported by State Key Laboratory of New Ceramic and Fine Processing Tsinghua UniversityProject(CXZZ12_0415) supported by Innovation Foundation for Graduate Students of Jiangsu Province,China
文摘The effects of alkali oxides （Na2O and K2O addition on both the sintering behavior and dielectric properties of Ca-AI-B-Si-O glass/Al2O3 composites were investigated by Fourier transform infrared spectroscopy （FTIR）, differential scanning calorimeter （DSC）, X-ray diffractometry （XRD） and scanning electron microscopy （SEM）. The results show that the increasing amount of alkali oxides in the glass causes the decrease of [SiO4], which results in the decrease of the continuity of glass network, and leads to the decrease of the softening temperature Tf of the samples and the increasing trend of crystallization. And that deduces corresponding rise of densification, dielectric constant, dielectric loss of the low temperature co-fired ceramic （LTCC） materials and the decrease of its thermal conductivity. By contrast, the borosilicate glass/A1203 composites with 1.5% （mass fraction） alkali oxides sintered at 875 ℃ for 30 rain exhibit better properties of a bulk density of 2.79 g/cm3, a porosity of 0.48%, a 2 value of 2.28 W/（m.K）, a er value of 7.82 and a tand value of 9.1 × 10-4 （measured at 10 MHz）.
基金supported by the National Natural Science Foundation of China(60374048,60977031)Jilin Provincial Science and Technology Department(20060928,20080330)+2 种基金Seed Foundations of Jilin University,China(2006-2008)National High-Tech Research and Development Program of China(863)(2009AA032402)Doctoral Found of Ministry of Education of China(20090061110040)~~
文摘NiO-La0.3Ce0.7O2-δ(LDC30) novel anode was investigated for IT-SOFCs(Intermediate Temperature-Solid Oxide Fuel Cells) with LaGaO3-based electrolyte. The results showed that LDC30 has a suitable chemical compatibility with NiO and NiO-LDC30 has a good thermal expansion matching with LDC30 interlayer and LSGM(La0.8Sr0.2Ga0.8Mg0.2O3-δ) electrolyte, so NiO-LDC30/LDC30 was considered as a feasible and novel anode system. It was also shown that NiO content plays a key role on polarization performance and morphology of the anode. When the content of NiO was 60%(mass fraction), the polarization loss of anode was the lowest. Next we will optimize the porosity and sintering procedure to modify the microstructure and performance of the anode.
文摘ZHOU Bai-Bin *,1,2 WEI Yong-De 1 LI Zhong-Hua 1 ( 1 Department of Applied Chemistry,Ha rbin Institute of Technology ￡?Harbin￡±￡ì￡°￡°￡°￡±￡(c)( 2 Department of Chemistry,Harbin Normal University￡?Harbin￡±￡ì￡°￡°￡?￡°￡(c) The air-solid interface reaction of Ce,Lu with K10 H 3[Gd (SiMo 4 W￡*O￡3￡1￡(c) 2]through chemistry-heated permeation is reported for the fi rst time￡(r)The permeated complex is characterized by ICP and the result shows tha t the mini mum Ce,Lu can permeate into the inner sph ere of K 10 H ￡3 ￡?Gd ￡¨SiMo ￡′ W ￡* O ￡3￡1 ￡(c) 2]The IR ,XRD patterns give the eviden ce that after permeation the comple x still keeps the Keggin structure,howe ver,its crystal structure is different from the complex before permeation￡(r)The cond uctivity of the permeated complex has been measured with the four-electr ode method and the data show that the co nductivity of the complex after permeation is 10 6 times higher than that of the sample before permeation and reaches ￡′￡(r)84 6×10 -1 S·cm -1 ￡(r)These indicate that the permeated c omplex is a good solid electrolyte and further appli cations are also expected￡(r)
