(1. 重慶大學(xué) 化學(xué)化工學(xué)院，重慶 400030；
2. 重慶工商大學(xué) 環(huán)境與生物工程學(xué)院，重慶 400067)
摘 要: 以水熱法自制γ-MnOOH和LiOH？H2O為原料，在較低溫度下固相反應(yīng)制備出尖晶石型Li4Mn5O12，經(jīng)酸浸脫鋰后得到對Li+具有特殊選擇性的MnO2離子篩。研究該離子篩對Li+的吸附性能和選擇性，并用XRD、SEM和FT-IR等和Li+選擇性吸附研究固相反應(yīng)工藝對離子篩材料結(jié)構(gòu)、化學(xué)組成及離子交換性質(zhì)的影響。結(jié)果表明：煅燒時(shí)間對前驅(qū)體的生成有較大影響，由400 ℃煅燒32 h所得的前驅(qū)體為純相Li4Mn5O12化合物，經(jīng)酸浸脫鋰后的離子篩仍保持與前驅(qū)體相同的尖晶石結(jié)構(gòu)；錳源γ-MnOOH、前驅(qū)體Li4Mn5O12和離子篩MnO2均為低維棒狀結(jié)構(gòu)形貌；離子篩對鋰的吸附速率符合一級動(dòng)力學(xué)Lagergren方程，飽和吸附容量為40.2 mg/g，并具有較好的Li+選擇性。
關(guān)鍵字: Li4Mn5O12；離子篩；前驅(qū)體；吸附
（1. College of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400030, China;
2. School of Environmental and Biological Engineering, Chongqing Technology and Business University,
Chongqing 400067, China）
Abstract:Spinel-type Li4Mn5O12 precursors were synthesized from γ-MnOOH self-prepared by hydro-thermal method and LiOH·H2O by low temperature solid-phase reaction. Furthermore, MnO2 ion-sieves with Li+ selective adsorption property were prepared by the acid treatment process to extract Li+ from the spinel Li4Mn5O12 precursor. The effects of solid-phase reaction process on the structure, chemical composition and ion-exchange property of the ion-sieve material were investigated by XRD, SEM, FT-IR and Li+ selective adsorption measurements. The results show that calcination time has the considerable effect on the precursor. The precursor synthesized at 400 ℃ for 32 h is a pure Li4Mn5O12. Final MnO2 ion-sieve and Li4Mn5O12 precursor have a low-dimensional rod-like morphology link γ-MnOOH and share the same structure of spinel. The adsorption rate of ion-sieve is consistent with the pseudo-first order kinetic equation of Lagergren. The Li+ saturated adsorption capacity is 40.2 mg/g, and the ion-sieve shows good Li+ selection.
Key words: Li4Mn5O12; ion-sieve; precursor; adsorption
