研究了氟碳铈矿在焙烧过程中空气湿度对氟逸出的影响,采用气相色谱法对不同条件下焙烧过程中气相中的氟含量进行了测定。结果表明,随着空气湿度的增加和焙烧温度的提高,气相中的氟含量大幅度提高,并证明了氟碳铈矿在焙烧过程中氟逸出的基本条件是水蒸气的存在,其脱氟机理是水蒸气与氟碳铈矿中的氟反应生成HF逸出。通过控制一定的条件,可以将氟碳铈矿中的氟完全脱出,并可以采用NaOH完全吸收利用。氟碳铈矿在焙烧过程中主要发生氟碳铈矿的分解反应、水蒸气与氟的反应和铈的氧化反应。
Effect of RH on fluorine escaping course during the roasting of bastnaesite was studied.The content of fluorine in gas was measured by the gas chromatographic analysis under different conditions.The results showed that the content of fluorine in gas was greatly improved with the increase of RH and roasting temperature.It proved that vapor in air was the basic requirement to make fluorine in bastnaesite escaping.The mechanism of fluorine escaping was that vapor reacts with fluorine to produce HF.By varying the conditions,fluorine in bastnaesite will completely escape and it can be absorbed by NaOH solution.The reactions during the roasting course of bastnaesite were decomposition reaction of bastnaesite,combination reaction of vapor and fluorine and oxidation reaction of Ce.