Experimental and modeling study of the aqueous solubility of vanadium(V) incorporated by solid solution in apatite phases

为了了解火山地区含水层中钒浓度的升高，以及钒对人体骨骼系统的毒性作用，将研究磷酸盐和钒酸盐磷灰石相之间的固溶体的溶度积。羟基磷灰石和氟磷灰石系列将被调查。混合磷酸盐/钒酸盐磷灰石的合成将基于碱性介质中的一步水溶液法进行。将在同步加速器设施中使用XRD和EXAFS分析对钒酸盐取代磷酸盐进行结构分析。 将进行的数据的理论解释的基础上，使用李普曼方程的二元磷酸盐-钒酸盐磷灰石系列的固溶体-水溶液平衡方法，并通过使用吉布斯能量最小化代码GEMS。这项工作的目的是预测在任何钒分数纳入磷灰石主相的钒溶解度。

To understand the elevated vanadium concentrations in aquifers of volcanic areas, and also the toxic effects of vanadium on the human skeletal system, the solubility products of the solid solutions between phosphate and vanadate apatite phases will be investigated. Both hydroxyapatite and fluorapatite series will be investigated. The synthesis of the mixed phosphate/vanadate apatites will be performed on the basis of a one-step aqueous method in alkaline media. Structural analysis of the phosphate substitution by vanadate will be performed using XRD and EXAFS analysis at a synchrotron facility. A theoretical interpretation of the data will be performed based on the solid-solution aqueous-solution equilibrium approach for the binary phosphate-vanadate apatite series using Lippmann equations, and also by using the Gibbs energy minimization code GEMS. The aim of this effort is to predict the vanadium solubility at any vanadium fraction incorporated in the apatite host phase.