KOH亚熔盐法分解钛铁矿

Decomposition of Ilmenite in KOH Sub-molten Salt

以KOH亚熔盐为反应介质,研究了KOH浓度、反应温度与时间、搅拌速率和碱/矿比等因素对钛铁矿在KOH亚熔盐体系中分解率的影响.结果表明,反应温度、反应时间及KOH浓度为主要影响因素,提高反应温度及KOH浓度均有利于钛铁矿在KOH亚熔盐中的分解,但当反应温度超过260℃时,钛铁矿的分解率又随反应温度的升高而降低;在KOH浓度80%(ω)、搅拌速度700r/min、反应温度260℃、碱/矿质量比5、反应时间180min的条件下,钛铁矿在KOH亚熔盐中的分解率超过95%.此外,钛铁矿在KOH亚熔盐中的分解符合未反应收缩核模型,受界面化学反应控制.

Using KOH sub-molten salt as reaction medium, the effects of KOH concentration, reaction temperature, time, stirring speed and mass ratio of alkali to ore on the decomposition rate of ilmenite in KOH sub-molten salt were investigated through factorial and orthogonal experiments. The results showed that the more important factors among them were reaction temperature, time and KOH concentration. The high reaction temperature and KOH concentration were beneficial to the decomposition rate of ilmenite in KOH sub-molten salt. However, the decomposition rate of ilmenite decreased when the reaction temperature was more than 260 ℃. The decomposition rate of ilmenite was above 95% under the reaction conditions of KOH concentration 80%（to）, stirring speed 700 r/min, reaction temperature 260 ℃, alkali-to-ore 5 and the reaction time 180 min. Furthermore, the decomposing process of ilmenite in KOH sub-molten salt was well interpreted with an unreacted shrinking core model under chemical reaction control.