Crystal Chemistry of Vanadium-Bearing Ellestadite Waste Forms.
Crystal Chemistry of Vanadium-Bearing Ellestadite Waste Forms.
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DOI：
10.1021/acs.inorgchem.8b01160
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发表时间：
2018-07
影响因子：
4.6
通讯作者：
Yanan Fang;S. Page;Gregory J Rees;M. Avdeev;J. Hanna;T. White
中科院分区：
文献类型：
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作者：
Yanan Fang;S. Page;Gregory J Rees;M. Avdeev;J. Hanna;T. White
合成了用于五价有毒金属（V，Cr，As）固定的钒酸钙钛矿Ca 10（SiO 4）x（VO 4）6- 2x（SO 4）xCl 2，并通过粉末X射线衍射（PXRD）、中子衍射（PND）、电子探针（EPMA）、傅里叶变换红外光谱（FTIR）和固体核磁共振（SS-NMR）对其进行了表征。钙钛矿0.19 < x < 3为P63/ m结构，钒酸盐端元Ca_（10）（VO_4）_6Cl_2为三斜晶系，空间群为P1 ~（？）对于0.77 < x < 2.44，存在可解释性间隙。结构中Cl的缺乏导致隧道中的短程无序。毒性特征浸出测试（TCLP）表明，钒的掺入增加了易硫钙石的溶解度，并定义了一个废物负荷限制，不应超过25原子%的V，以确保小的释放水平。
Vanadate ellestadites Ca10(SiO4) x(VO4)6-2 x(SO4) xCl2, serving as prototype crystalline matrices for the fixation of pentavalent toxic metals (V, Cr, As), were synthesized and characterized by powder X-ray and neutron diffraction (PXRD and PND), electron probe microanalysis (EPMA), Fourier transform infrared spectroscopy (FTIR), and solid-state nuclear magnetic resonance (SS-NMR). The ellestadites 0.19 < x < 3 adopt the P63/ m structure, while the vanadate endmember Ca10(VO4)6Cl2 is triclinic with space group P1̅. A miscibility gap exists for 0.77 < x < 2.44. The deficiency of Cl in the structure leads to short-range disorder in the tunnel. Toxicity characteristic leaching testing (TCLP) showed the incorporation of vanadium increases ellestadite solubility, and defined a waste loading limit that should not exceed 25 atom % V to ensure small release levels.