摘要
以氯化锂、无水氯化铝为原料,通过正交实验优化反应合成条件,采用"一步法"制备Li Cl·2Al(OH)3·n H2O型铝基锂吸附剂。分别探究了吸附时间、吸附温度、溶液初始p H、溶液初始Li+浓度对吸附性能的影响,对吸附前后的无机铝吸附材料做了表征,并考察了吸附剂的离子选择吸附性及稳定性能。结果表明:最佳吸附条件为在45℃下p H=7的锂溶液中吸附2 h,吸附容量高达到8.66 mg/g。XRD、FT-IR表征结果表明:所制吸附材料有良好的稳定性。且该吸附剂对Li+分配系数(K=10.06)远高于其他金属阳离子,吸附材料经5次循环使用后,吸附容量仍能保持原来的91.5%。在西藏龙木错盐湖卤水中,对锂的吸附量达到5.24 mg/g。吸附平衡数据拟合结果表明:铝基锂吸附剂符合Langmuir等温吸附模型,吸附是发生在吸附剂表面的单层吸附;吸附过程符合伪二级动力学,是典型的化学吸附过程。
Aluminum-based lithium adsorbent[Li Cl·2Al(OH)3·n H2O]was synthesized with Li Cl and anhydrous Al Cl3as raw materials by one-step method,and the reaction conditions was optimized by orthogonal experiment.The effects of adsorption time,adsorption temperature,initial p H and initial Li+concentration on adsorption performance were investigated.The inorganic aluminum adsorption materials were characterized before and after adsorption.The selectivity of ion adsorption and stability of adsorbent were also discussed.The results showed that the optimum adsorption condition was 2 h in lithium solution with p H=7 at 45℃,and the adsorption capacity reached 8.66 mg/g.The results of XRD and FT-IR showed that the adsorbent material had good stability.The Li+distribution coefficient of adsorbent(K=10.06)was much higher than that of other metal cations.After 5 cycles of adsorption,the adsorption capacity of the adsorbent can still maintain 91.5%of original value.And the lithium adsorption amount in Tibet Longmucuo brine reached 5.24 mg/g.The fitting results of adsorption equilibrium data showed that the adsorption of Al-based lithium adsorbent conforms to the Langmuir isothermal adsorption model,and the adsorption belongs to single layer adsorption which occurred on the surface of the adsorbent.The adsorption process accords with pseudo-second-order kinetics equation,which is a typical chemical adsorption process.
作者
唐娜
龚经款
项军
Tang Na;Gong Jingkuan;Xiang Jun(College of Chemical Engineering and Material Science,Tianjin University of Science and Technology,Tianjin 300457,China)
出处
《无机盐工业》
CAS
CSCD
北大核心
2020年第8期51-56,共6页
Inorganic Chemicals Industry
基金
天津市自然科学基金资助项目(18JCZDJC37200)。
关键词
氢氧化铝
吸附剂
锂离子
选择性
aluminum hydroxide
adsorbent
lithium ion
selectivity
