真空铝热还原炼锂新工艺中富锂熟料的制备

常压煅烧氢氧化锂、氧化铝和氧化钙混合物得到富锂熟料,真空铝热还原该熟料得到金属锂及可制备氢氧化铝的12Ca O·7Al2O3型还原渣.研究了制团压力、煅烧温度、煅烧时间对煅烧烧损率及锂还原率的影响.结果表明:在制团压力为30 MPa,煅烧温度为750~800℃,煅烧时间为60~90 min的条件下,烧损率基本保持在34%左右;该条件所得富锂熟料在还原温度1 100℃,还原时间90 min,铝粉不过量的条件下进行真空铝热还原得到锂还原率较高.该煅烧工艺适用于真空铝热还原炼锂新工艺中富锂熟料的制备.

Preparation of Lithium-Rich Clinker in New Vacuum Aluminothermy Reduction of Lithium Process

A new vacuum aluminothermy reduction of lithium process was developed， in which lithium hydroxide， alumina and calcium oxide mixture were used as raw materials. Lithium-rich clinker was prepared by calcining the mixture of raw materials. Metal lithium and reduction slag contained the 12CaO·7Al2O3 which was used to form aluminum hydroxide were produced by the vacuum aluminothermy reduction process. Effects of briquette pressure， calcination temperature and time on the burning loss rate and lithium reduction rate were investigated. The result showed that the burning loss rate remained about 34% under the conditions of briquette pressure 30MPa， calcination temperature 750~800℃ and calcination time 60~90min. The lithium reduction rate was relatively high when the lithium-rich clinker obtained under the above conditions were used to vacuum aluminothermy reduction under the conditions of reduction temperature 1100℃， reduction time 90min and theoretical aluminum addition mass. This kind of calcination process was suitable to the preparation of lithium-rich clinker for the new vacuum aluminothermy reduction of lithium.