制备高品质沸腾氯化富钛料是钛白生产中的重要环节。采用X射线荧光光谱仪(XRF)、X射线衍射仪(XRD)和扫描电镜(SEM)等分析手段对攀枝花钛渣和钛精矿在氧化还原改性-盐酸法制备富钛料工艺进行了系统的对比研究。结果表明,钛铁矿和钛渣均...制备高品质沸腾氯化富钛料是钛白生产中的重要环节。采用X射线荧光光谱仪(XRF)、X射线衍射仪(XRD)和扫描电镜(SEM)等分析手段对攀枝花钛渣和钛精矿在氧化还原改性-盐酸法制备富钛料工艺进行了系统的对比研究。结果表明,钛铁矿和钛渣均保持致密结构,且都含有少量酸溶性差的硅酸盐相,但是两者的主要物相分别为酸溶性好的M2O3型固溶体(主要为Fe Ti O3)和酸溶性差的黑钛石M3O5型固溶体(包括Ti3O5,Mg2Ti O5和Fe Ti2O5等)。钛精矿经过改性后会变为多孔的Fe Ti O3,浸出反应活性非常高,常压浸出即可得到合格的沸腾氯化富钛料。而钛渣在现有的氧化还原-常压盐酸浸出工艺中的反应活性要比钛铁矿差很多,改性后钛渣仍有一定含量的难溶M3O5固溶体,且矿相致密结构未被完全破坏,常压浸出处理不能有效除杂,需要加压浸出才能得到高品位富钛料。另外,钛渣硅酸盐杂质相在整个改性和盐酸浸出过程中的变化不大。展开更多
Type‐II‐heterojunction TiO2nanorod arrays(NAs)are achieved by a combination of reduced and pristine TiO2NAs through a simple electrochemical reduction.The heterojunction‐structured TiO2NAs exhibit an enhanced photo...Type‐II‐heterojunction TiO2nanorod arrays(NAs)are achieved by a combination of reduced and pristine TiO2NAs through a simple electrochemical reduction.The heterojunction‐structured TiO2NAs exhibit an enhanced photo‐efficiency,with respect to those of pristine TiO2NAs and completely reduced black TiO2.The improved efficiency can be attributed to a synergistic effect of two contributions of the partially reduced TiO2NAs.The light absorption is significantly increased,from theUV to the visible spectrum.Moreover,the type II structure leads to enhanced separation and transport of the electrons and charges.The proposed electrochemical approach could be applied to various semiconductors for a control of the band structure and improved photoelectrochemical performance.展开更多
文摘制备高品质沸腾氯化富钛料是钛白生产中的重要环节。采用X射线荧光光谱仪(XRF)、X射线衍射仪(XRD)和扫描电镜(SEM)等分析手段对攀枝花钛渣和钛精矿在氧化还原改性-盐酸法制备富钛料工艺进行了系统的对比研究。结果表明,钛铁矿和钛渣均保持致密结构,且都含有少量酸溶性差的硅酸盐相,但是两者的主要物相分别为酸溶性好的M2O3型固溶体(主要为Fe Ti O3)和酸溶性差的黑钛石M3O5型固溶体(包括Ti3O5,Mg2Ti O5和Fe Ti2O5等)。钛精矿经过改性后会变为多孔的Fe Ti O3,浸出反应活性非常高,常压浸出即可得到合格的沸腾氯化富钛料。而钛渣在现有的氧化还原-常压盐酸浸出工艺中的反应活性要比钛铁矿差很多,改性后钛渣仍有一定含量的难溶M3O5固溶体,且矿相致密结构未被完全破坏,常压浸出处理不能有效除杂,需要加压浸出才能得到高品位富钛料。另外,钛渣硅酸盐杂质相在整个改性和盐酸浸出过程中的变化不大。
基金supported from the National Natural Science Foundation of China (21425309, 21761132002, 21703040)China Postdoctoral Science Foundation (2017M622051) the 111 Project~~
文摘Type‐II‐heterojunction TiO2nanorod arrays(NAs)are achieved by a combination of reduced and pristine TiO2NAs through a simple electrochemical reduction.The heterojunction‐structured TiO2NAs exhibit an enhanced photo‐efficiency,with respect to those of pristine TiO2NAs and completely reduced black TiO2.The improved efficiency can be attributed to a synergistic effect of two contributions of the partially reduced TiO2NAs.The light absorption is significantly increased,from theUV to the visible spectrum.Moreover,the type II structure leads to enhanced separation and transport of the electrons and charges.The proposed electrochemical approach could be applied to various semiconductors for a control of the band structure and improved photoelectrochemical performance.
