摘要
系统研究了草酸浸出赤泥中铁和铝的过程,探究了草酸浓度、反应时间、反应温度和液固比对铁和铝浸出率的影响。在此基础上,利用响应面实验优化浸出过程,同时采用太阳光照射草酸浸出液,将草酸铁还原成草酸亚铁沉淀,实现浸出液的回收再利用。结果表明:回归方程模型显著,草酸浸出赤泥的最佳工艺条件为草酸浓度为0.30 g/mL,液固比为14∶1,反应温度为95℃,反应时间为150 min。在此条件下,铁和铝的浸出率分别为87.76%和74.60%。太阳光照射催化浸出液420 min内,总铁含量从1.152 g/L下降至0.173 g/L,85%以上的草酸铁以草酸亚铁沉淀形式得以回收。再通过调节pH,过滤及蒸发结晶后可回收滤液中的铝和草酸。这为赤泥中铁和铝的回收提供了新的技术路线选择。
The process of extraction of iron and aluminum from red mud by using oxalic acid leaching was investigated systematically. The effect of oxalic acid addition, leaching time, leaching temperature and liquid to solid ratio on the leaching efficiency were investigated respectively, and the response surface method was used to the optimize the preparation process based on the single-factor experiment results. The Fe(Ⅲ) oxalate in the leaching solution was reduced to Fe(Ⅱ) oxalate by using sunlight irradiation. The experiment results showed that the regression equation model was of great significant. The optimized processing conditions for leaching rate were as follows: the oxalic acid concentration of 0.30 g/mL, the liquid-solid ratio of 14∶1, reaction temperature of 95 ℃, reaction time of 150 min. Under the optimal conditions, the leaching rates of iron and aluminum were up to 87.76% and 74.60%, respectively. The total iron concentration decreased from 1.152 g/L to 0.173 g/L in the extracted solution, and more than 85% Fe(Ⅲ) oxalate was transformed into the Fe(Ⅱ) oxalate crystallite within 420 min by using sunlight irradiation. The aluminum and oxalic acid in the filtrate could be recovered by means of adjusting pH value, filtration, and evaporation crystallization successively. The study provides new technical routine for the recovery of iron and aluminum from red mud.
作者
黄荃莅
黄魁
卢远桓
刘玉玲
熊昊
董海丽
HUANG Quan-li;HUANG Kui;LU Yuan-huan;LIU Yu-ling;XIONG Hao;DONG Hai-li(School of Resources,Environment and Materials,Guangxi University,Nanning 530004,China)
出处
《环境工程》
CAS
CSCD
北大核心
2021年第12期199-205,共7页
Environmental Engineering
基金
国家自然科学基金(21767003)
广西大学科研基金(XJZ140336)
广西大学广西有色金属及特色材料加工重点实验室开放基金(GXKFJ12-16,GXKFJ16-03)。
关键词
赤泥
草酸浸出
响应面
有价金属
red mud
oxalic acid leaching
response surface
valuable metals
作者简介
第一作者:黄荃莅(1995-),女,硕士研究生,主要研究方向为固体废弃物处理与处置。huangquanli0612@qq.com;通信作者:黄魁(1981-),男,副教授,主要研究方向为固体废弃物处理与处置。khuang@gxu.edu.cn。
