煅烧对管状羟基磷灰石固铀性能的影响

Effect of Calcination on the Properties of Tubular Hydroxyapatite for Uranium Consolidation

羟基磷灰石是一种对铀具有优异吸附性能的吸附剂,其固铀稳定性逐渐被关注。本文通过收集吸附高浓度含铀废水后的管状羟基磷灰石固相,对其进行不同温度的高温煅烧处理后,通过恒定pH浸出实验分析煅烧前后含铀固相的铀浸出率变化趋势,探究热固化对含铀羟基磷灰石抗浸出性能的作用。结果显示高温煅烧对管状羟基磷灰石的固铀作用略有加强,结合X射线粉末衍射和傅里叶转换红外光谱分析,固铀性能的提升是因为高温煅烧使含铀固化体的物相组成向磷酸铀酰发生转变,而磷酸铀酰在酸性环境下的稳定性更高。

Hydroxyapatite is an adsorbent with excellent adsorption performance on uranium,and its stability of uranium fixation is gradually attracting attention.In this paper,we investigated the effect of thermal curing on the anti-leaching performance of uranium-containing hydroxyapatite by collecting the solid phase of tubular hydroxyapatite after adsorption of highly concentrated uranium-containing wastewater and subjecting it to high-temperature calcination treatment at different temperatures,and analyzing the trend of uranium leaching rate of uranium-containing solid phase before and after calcination by constant pH leaching experiments.The results showed that the effect of high-temperature calcination on the uranium fixation of tubular hydroxyapatite was slightly enhanced.Combined with X-ray diffraction and Fourier Transform infrared spectroscopy,the enhancement of the uranium fixation performance was attributed to the transformation of the phase composition of the uranium-containing solids by high-temperature calcination toward uranyl phosphate,which is more stable in acidic environments.