摘要
本文用二次回归正交组合设计法,对用硫酸钠从湿法磷酸中脱氟生成氟硅酸钠过程中,MgO、Al_2O_3和Fe_1O_3等杂质及Na_2O对脱氟率的影响进行了研究.通过方差分析,得出数学模型.用文献数据和粗磷酸脱氟的实测数据对此模型进行了检验,脱氟率的计算值与实测值相对误差小于10％。用放置较长时间的湿法磷酸脱氟,可获得结晶粗大、便于过滤、洗涤的滤饼。用5％Na_2SO_4溶液充分洗涤后,所得氟硅酸钠符合二级品要求.
In this paper the effect of impurifies (Al_2O_3, MgO, Fe_2O_3) and Na_2O on the removal of fluorine from wet-process phosphoric acid (wpA) to produce Sodium Silicoflucride has been Studied With the help of Second-order regression othogonal composite design method After the analysis of the variance of variable effects, the mathematical model is Obtained. It is obvious in this equation that Impurity Al_2O_3 produces the most significant negative effect on the fluorine removal. The effect of MgO is less significant than Al_2O_3. But the interaction between A1_2O_3 and MgO Can not be overlooked. This model has been tested against literature values and fluorine removal data from crude WPA in the Laboratory. The agreement between calculated and experimental values are quite satisfactory.
关键词
磷酸
脱氟
湿法
磷矿石
氟硅酸钠
fluorine removal of phosphoricacid
phosphoric acid purification
fluorine removal
sodium silicofluoride
