Study on preparation and adsorption performance of chromium-iron composite doped lithium-ion sieve
The Li1 adsorption and separation from low concentration solution by lithium-ion sieve has become one of the most promising methods due to the high selectivity,adsorption capacity and adsorption rate towards lithium ion(Li+).However,the industrial application of lithium manganese oxide ion-sieve is limited due to its difficult recovery,high Mn dissolution loss rate and poor circulation performance.In this paper,the spinel-structure chromium-iron composite doped lithium-ion sieves were prepared by high-temperature solid state reac-tion method usingLiOH·H2O,MnO2,Fe2O3,and Cr2O3 as raw materials.The effects of Cr doping amounts and calcination temperature on the phase structure,adsorption performance,and Mn dissolution loss rate of the lithium-ion sieve precursors were investigated.The results showed that the adsorption capacity of the synthe-sized lithium-ion sieve could reach 27.30 mg/g and the Mn dissolution loss rate was only 0.43％when the molar ratio of Li,Mn,Fe and Cr was 1∶2∶0.05∶0.05 and the calcination temperature was 550 ℃.The selection ad-sorption experiments showed that the lithium-ion sieve presents excellent selection performance for Li+.Fur-thermore,the recycling performance of chromium-iron doped lithium-ion sieve showed that the adsorption ca-pacity could still remain 89％of the second cycle(18.51 mg/g)after five cycles,which is greater than 56％of the undoped lithium-ion sieve.
万方数据
维普
