摘要
本文采取纯氟磷灰石、活性炭和二氧化硅的粉粒做成型料，进行了磷矿热炭固态还原反应机理的试验研究，结果表明氟磷灰石在１５００℃的温度未发生脱氟与分解的反应；在１４００℃的温度也未被炭直接还原；二氧化硅能使氟磷灰石脱氟成磷酸三钙，氟在低硅钙摩尔比时形成２ＣａＦ２·ＳｉＯ２留于型料中，高硅钙摩尔比时形成ＳｉＦ４逸去。提出了氟磷灰石脱氟与磷酸三钙被炭还原的反应机理．
In this work, the powder of pure fluorapatite, active carbon and silica are mixed and shaped. This agglomerat is used to experimentally investigate the mechanism for the thermal solid reduction of phosphate ore by carbon. Defluorination and decomposition of the fluorapatite never occur at 1500℃,nor is the fluorapatite reduced by carbon without silica at 1400℃. However, in presence of silica,fluorapatite will defluorinate to produce tricalcium phosphate. Coincidentally, 2CaF2. SiO2 is produced and remains in the agglomerats for lower silica-lime ratios and SiF4 is evolved into gas phase for higher silica-lime ratios.The reaction mechanism is presented as, the foluorapatite deflurinate to produce tricalcium phosphate and then the product is reduced by carbon.
基金
国家自然科学基金
关键词
氟磷灰石
还原
反应机理
磷酸盐
reduction of fluorapatite, mechanism of solid-solid reaction,high temperature reaction
