Extraction Of Lithium And Beryllium From Lithium-containing Chrysoberyl Beryllium Ore

Lithium and Beryllium are signi:ficant strategic resource.The market demand of lithium has been steadily rising;The high-grade beryl ore is becoming exhausted at present,It is of great significance to develop and utilize the non-beryl beryllium mineral resources,just like Chrysoberyl and Bertrandite.This paper takes the lithium-containing chrysoberyl beryllium ore as the research object which was obtained from Xianghualing mining area of chenzhou in hunan province.A new process of "Microwave roasting—Sulphuric acid leaching-Extraction and reverse extraction enrichment—Preparation of beryllium hydroxide and lithium carbonate"was used to study the extraction of lithium and beryllium.(1)The process mineralogy of the ore samples was carried out.The average grade of BeO and Li2O in ore samples is 0.26%and 0.39%.Beryllium and lithium were mainly found in the form of Chrysoberyl and Zinnwaldite,and were enwrapped by fluorite and gangue minerals.(2)The result of the direct acid leaching experiment with non-roasting was unsatisfactory,not only was leaching efficiency low but also more sulfuric acid dosage was needed.The result of the acid leaching experiment with conventional-roasting was ordinary,the leaching efficiency has been improved and the sulfuric acidconsumption has been reduced;The results of the acid leaching experiment with microwave-roasting was ideal.The leaching efficiency of Lithium and Beryllium were up to 95.0%and 84.0%via replication experiments.As the result of the test:microwave roasting 900 0C and 1h;Sulfuric acid leaching 90 ℃ and 4h、Acid ore ratio(60%),liquid-solid ratio 3/1,stirring intensity 360 r/min.(3)Materials of the experiments of the extraction and reverse extraction were lixivium with pretreatment.The effects of composition of the mixer extractant,concentration and pH of extraction liquid,oil-aqueous ratio,temperature and time of extraction,kinds and concentration of stripping agent,oil-aqueous ratio,temperature and time of reverse extraction on extraction efficiency about Lithium and Beryllium were investigated.The optimum parameters about extraction are as mentioned below:volume ratio of P204:TBP:260#=3:1:6,concentration of BeO in extraction liquid 0.5～1.2 g/L(Li2O:0.85～2.0 g/L),pH 3.0,oil-aqueous ratio O/A 1:3,stirring intensity 450 r/min,temperature 35 ℃,time of extraction 16 min,stripping agent NaOH(aq),concentration of stripping agent 100 g/L(2.5 mol/L),oil-aqueous ratio O/A(reverse extraction)3:1,time of reverse extraction 10 min.Extraction effect of this condition is satisfactory.One stage extraction yield of Lithium and Beryllium is over 79%and 85%,One stage reverse extraction yield of Lithium and Beryllium are over 95%both.With the optimal conditions,five stage countercurrent extraction yield of Lithium and Beryllium is 93.1%and 96.9%;five stage countercurrent counter extraction yield of Lithium and Beryllium is 97.2%and 98.1%.Finally,we can obtain stripping solution which was rich in Lithium and Beryllium by repeated test.In the stripping solution,the concentration of Li2O and BeO is 15.087 g/L and 9.303 g/L on average.We can prepare Be(OH)2 and Li2CO3 in this solution.Under the optimum parameters,total recovery rate of Li2O and BeO is 85.9%and 79.8%。...