A multi-phase slag containing Na2O is potential to efficiently dephosphorize high-P hot metal.After dephosphorization,the generated slag with high P2O5 content is regarded as a P resource.Because P2O5 was mainly conce...A multi-phase slag containing Na2O is potential to efficiently dephosphorize high-P hot metal.After dephosphorization,the generated slag with high P2O5 content is regarded as a P resource.Because P2O5 was mainly concentrated in the 2CaO SiO2-3CaO P2O5 solid solution,the recovery of P from dephosphorization slag primarily depends on the separation of the solid solution from other phases.The distribution ratios of P2O5 between solid solution and liquid phase in the CaOSiO2-FeO-P2O5-Nslag system were investigated.The results indicated that the addition of Na2O facilitated the enrichment of P2O5 in the solid solution because it increased not only the distribution ratio of P2O5 but also the mass fraction of the solid solution.The distribution ratio of P2O5 was independent of the P2O5 content in slag.A higher P2O5 content in slag resulted in higher P2O5 and Na2O contents in the solid solution.The distribution ratio of P2O5 increased with the total Fe content in the liquid phase,regardless of the valence of Fe.An increase in the FeO content in slag brought a higher P2O5 content in the solid solution.As slag basicity increased,the distribution ratio of P2O5 increased,but the P2O5 content in the solid solution decreased.展开更多
(Fe7Co3)0.15(SiO2)0.85 granular alloy solid was prepared successfully using sol-gel method. The samples with different reducing temperatures were investigated by X-ray diffractometer(XRD),transmission electron microgr...(Fe7Co3)0.15(SiO2)0.85 granular alloy solid was prepared successfully using sol-gel method. The samples with different reducing temperatures were investigated by X-ray diffractometer(XRD),transmission electron micrography(TEM) and vibrating sample magnetometer(VSM). The av-erage particIe sizes of the samples were also calculated from Scherrer formula. The magnetic properties of (Fe7Co3 )o. 15 (SiO2)0.85 were studied in detail.展开更多
In order to explore synthetic method of pure sodium pyroxene,the pure chemical reagents of Na2CO3,Fe（OH）3 and H2SiO3were used as raw materials,and the possible solid phase reactions for Na2CO3-Fe（OH）3-H2SiO3system...In order to explore synthetic method of pure sodium pyroxene,the pure chemical reagents of Na2CO3,Fe（OH）3 and H2SiO3were used as raw materials,and the possible solid phase reactions for Na2CO3-Fe（OH）3-H2SiO3system in heating process had been studied by means of differential thermal analysis（DTA）and X-ray diffraction（XRD）. The influencing factors of sodium pyroxene（NaFeSi2O6）synthetic reaction,such as sintering temperature and holding time,had also been studied.The results show that sodium pyroxene can be largely synthesized at 737℃;it is helpful for synthesis of sodium pyroxene to increase sintering temperature appropriately,and the best temperature should be controlled at 900℃or so,because it will melt and decompose at temperatures higher than 900℃.In those influencing factors of sodium pyroxene synthesis the most important is temperature.The results will be helpful for providing pure NaFeSi2O6for further research on the formation of SFCA for NaFeSi2O6-KAlSi2O3-CaO-Fe2O3-CaF2 system in the sintering process of Bayan-obo iron ore.展开更多
A series of SO 2- 4/TiO 2 SiO 2 catalysts with different mass fractions of SiO 2 were prepared by sol gel method. The effect of adding SiO 2 on the crystal structure, specific surface area, oxygen adsorption, and acid...A series of SO 2- 4/TiO 2 SiO 2 catalysts with different mass fractions of SiO 2 were prepared by sol gel method. The effect of adding SiO 2 on the crystal structure, specific surface area, oxygen adsorption, and acidity of SO 2- 4/TiO 2 catalyst and its photocatalytic property for degradation of bromomethane was studied. The results showed that the specific surface area and amount of oxygen adsorption of catalyst were increased by addition of SiO 2, leading to the obvious increase on photocatalytic activity of SO 2- 4/TiO 2 SiO 2 catalysts and mineralization ratio of bromomethane. Comparing with SO 2- 4/TiO 2, the acidic strength and anti moisture ability of SO 2- 4/TiO 2 SiO 2 catalyst were decreased.展开更多
SO2-4–Mo O3–Zr O2–Nd2O3/Si O2（SMZN/Si O2） catalysts for the production of biodiesel via both esterification and transesterification were prepared and characterized by N2adsorption-desorption isotherms,X-ray diffr...SO2-4–Mo O3–Zr O2–Nd2O3/Si O2（SMZN/Si O2） catalysts for the production of biodiesel via both esterification and transesterification were prepared and characterized by N2adsorption-desorption isotherms,X-ray diffraction（XRD）,scanning electron microscopy（SEM）,thermogravimetry analysis（TGA）,ammonia adsorption Fourier transform infrared spectra（NH3-FTIR）,and ammonia adsorption temperature programmed desorption（NH3-TPD） to reveal the dependence of the stable catalytic activity on calcination time. The reason for catalyst deactivation was also studied. The calcination time remarkably affected the types of active centers on SMZN/Si O2-2,and 4 h was found to be the optimal calcination time. SO4 species bonded with small size Zr O2 were found to be the stable active centers,where the leaching of SO2-4and the deposition of coke were inhibited. The deposition of coke was easier on large size Zr O2 than on small size ones. Calcination in air flow could eliminate the deposited coke to recover the deactivated catalysts.展开更多
Biodiesel was synthesized from soybean oil by transesterification over Li_2SiO_3 catalyst.The Li_2SiO_3 can be used for biodiesel production directly without further drying or thermal pretreatment,no obvious differenc...Biodiesel was synthesized from soybean oil by transesterification over Li_2SiO_3 catalyst.The Li_2SiO_3 can be used for biodiesel production directly without further drying or thermal pretreatment,no obvious difference in the FAME conversion（92.4-96.7%） between the air-exposed catalyst（24-72 h） and the fresh one（94.2%）.This leads to important benefits when considering industrial applications of Li_2SiO_3 as a solid catalyst for storing and handling catalyst without taking special actions.展开更多
基金This work was financially supported by the National Natural Science Foundation of China(Nos.51704010,51604003,U1760117)Key Laboratory Open Project Fund of Metallurgical Emission Reduction and Resources Recycling(Anhui University of Technology)Ministry of Education(JKF18-02).
文摘A multi-phase slag containing Na2O is potential to efficiently dephosphorize high-P hot metal.After dephosphorization,the generated slag with high P2O5 content is regarded as a P resource.Because P2O5 was mainly concentrated in the 2CaO SiO2-3CaO P2O5 solid solution,the recovery of P from dephosphorization slag primarily depends on the separation of the solid solution from other phases.The distribution ratios of P2O5 between solid solution and liquid phase in the CaOSiO2-FeO-P2O5-Nslag system were investigated.The results indicated that the addition of Na2O facilitated the enrichment of P2O5 in the solid solution because it increased not only the distribution ratio of P2O5 but also the mass fraction of the solid solution.The distribution ratio of P2O5 was independent of the P2O5 content in slag.A higher P2O5 content in slag resulted in higher P2O5 and Na2O contents in the solid solution.The distribution ratio of P2O5 increased with the total Fe content in the liquid phase,regardless of the valence of Fe.An increase in the FeO content in slag brought a higher P2O5 content in the solid solution.As slag basicity increased,the distribution ratio of P2O5 increased,but the P2O5 content in the solid solution decreased.
文摘(Fe7Co3)0.15(SiO2)0.85 granular alloy solid was prepared successfully using sol-gel method. The samples with different reducing temperatures were investigated by X-ray diffractometer(XRD),transmission electron micrography(TEM) and vibrating sample magnetometer(VSM). The av-erage particIe sizes of the samples were also calculated from Scherrer formula. The magnetic properties of (Fe7Co3 )o. 15 (SiO2)0.85 were studied in detail.
基金Item Sponsored by National Natural Science Foundation of China (50944049)
文摘In order to explore synthetic method of pure sodium pyroxene,the pure chemical reagents of Na2CO3,Fe（OH）3 and H2SiO3were used as raw materials,and the possible solid phase reactions for Na2CO3-Fe（OH）3-H2SiO3system in heating process had been studied by means of differential thermal analysis（DTA）and X-ray diffraction（XRD）. The influencing factors of sodium pyroxene（NaFeSi2O6）synthetic reaction,such as sintering temperature and holding time,had also been studied.The results show that sodium pyroxene can be largely synthesized at 737℃;it is helpful for synthesis of sodium pyroxene to increase sintering temperature appropriately,and the best temperature should be controlled at 900℃or so,because it will melt and decompose at temperatures higher than 900℃.In those influencing factors of sodium pyroxene synthesis the most important is temperature.The results will be helpful for providing pure NaFeSi2O6for further research on the formation of SFCA for NaFeSi2O6-KAlSi2O3-CaO-Fe2O3-CaF2 system in the sintering process of Bayan-obo iron ore.
文摘A series of SO 2- 4/TiO 2 SiO 2 catalysts with different mass fractions of SiO 2 were prepared by sol gel method. The effect of adding SiO 2 on the crystal structure, specific surface area, oxygen adsorption, and acidity of SO 2- 4/TiO 2 catalyst and its photocatalytic property for degradation of bromomethane was studied. The results showed that the specific surface area and amount of oxygen adsorption of catalyst were increased by addition of SiO 2, leading to the obvious increase on photocatalytic activity of SO 2- 4/TiO 2 SiO 2 catalysts and mineralization ratio of bromomethane. Comparing with SO 2- 4/TiO 2, the acidic strength and anti moisture ability of SO 2- 4/TiO 2 SiO 2 catalyst were decreased.
基金supported by the National Nature Science Foundation of China (no.21106089)
文摘SO2-4–Mo O3–Zr O2–Nd2O3/Si O2（SMZN/Si O2） catalysts for the production of biodiesel via both esterification and transesterification were prepared and characterized by N2adsorption-desorption isotherms,X-ray diffraction（XRD）,scanning electron microscopy（SEM）,thermogravimetry analysis（TGA）,ammonia adsorption Fourier transform infrared spectra（NH3-FTIR）,and ammonia adsorption temperature programmed desorption（NH3-TPD） to reveal the dependence of the stable catalytic activity on calcination time. The reason for catalyst deactivation was also studied. The calcination time remarkably affected the types of active centers on SMZN/Si O2-2,and 4 h was found to be the optimal calcination time. SO4 species bonded with small size Zr O2 were found to be the stable active centers,where the leaching of SO2-4and the deposition of coke were inhibited. The deposition of coke was easier on large size Zr O2 than on small size ones. Calcination in air flow could eliminate the deposited coke to recover the deactivated catalysts.
文摘Biodiesel was synthesized from soybean oil by transesterification over Li_2SiO_3 catalyst.The Li_2SiO_3 can be used for biodiesel production directly without further drying or thermal pretreatment,no obvious difference in the FAME conversion（92.4-96.7%） between the air-exposed catalyst（24-72 h） and the fresh one（94.2%）.This leads to important benefits when considering industrial applications of Li_2SiO_3 as a solid catalyst for storing and handling catalyst without taking special actions.
