超声波强化浸出高品位混合稀土精矿

Enhanced Leaching Process of High-Grade Mixed Rare Earth Concentrate with Ultrasonic Technology

针对目前混合稀土精矿提取稀土工艺过程中存在的稀土浸出率低、浸出时间长、产品纯度低、"三废"污染严重等问题,采用超声波强化浸出过程,利用化学分析、X射线衍射(XRD)等实验手段表征了酸浸过程中HCl浓度、固液比、酸浸时间、酸浸温度、超声频率对稀土提取过程的影响。实验结果表明:当HCl浓度为7 mol·L-1、固液比为1∶3.77、酸浸时间为50 min、酸浸温度为60℃、超声功率为70 W时,稀土浸出率和Ce浸出率可以达到64.01%和69.26%;稀土浸出率和Ce浸出率均比无超声波强化浸出分别提高了24.40%和26.91%;当反应时间延长至180 min,无超声波强化浸出的稀土浸出率和Ce浸出率与反应时间为50 min时的超声强化浸出基本相同,但超声强化浸出的反应时间相比无超声波强化浸出的反应时间却缩短了72.22%,超声波对于混合稀土精矿的浸出具有明显的强化作用。

Aiming at low rate,low product purity,long leaching time＂three wastes＂pollution and other issues during the rare earth extraction process at present,the effect of HCl concentration,solid to liquid ratio,leaching time,leaching temperature,and ultrasonic frequency on rare earth extraction was studied by means of chemical analysis,X-ray diffraction（XRD） and other experimental methods during the ultrasonic strengthening and the acid leaching process.The experimental results showed that when the HCl concentration was7 mol·L^-1,the ratio of solid to liquid was 1∶ 3.77,acid leaching time was 50 min,acid leaching temperature was 60 ℃,and the ultrasonic power was 70 W,the rare earth leaching rate and leaching rate of Ce could reach 64.01% and 69.26%,respectively,which were increased by 24.40% and 26.91% than those without ultrasound strengthening.When the ultrasonic reaction time was extended to 180 min,leaching rates of rare earth and Ce without ultrasonic strengthening were the same as that when the ultrasonic reaction time was 50 min.But the reaction time was 72.22% shorter than that without ultrasonic strengthening.So the results showed that ultrasound had an obvious strengthening effect on mixed rare earth concentrate leaching.