氯化钪-氯化钠-氯化钾熔盐制备新工艺研究

Manufacture of Anhydrous Scandium Chloride-Sodium Chloride-Potassium Chloride Molten Salt

研究了以Sc2O3为原料,盐酸回流溶解后与NaCl,KCl,NH4Cl溶液混合,经蒸发浓缩、结晶、真空预脱水,再在氩气保护下分段升温脱水、升华除去过量NH4Cl后制备ScCl3 NaCl KCl熔盐的新工艺。研究表明,添加NH4Cl后加热脱水时,NH4Cl分解产生的HCl气体能抑制Sc Cl3水合物加热过程中的水解,溶解产生的水不溶性钪,从而有效地防止了Sc2O3等水不溶化合物的生成。制备的ScCl3 NaCl KCl熔盐脱水完全、水不溶性钪含量很低,能满足熔盐金属热还原法制备金属钪及铝钪中间合金对熔盐原料的要求。

A new kind of manufacture technology of scandium chloridesodium chloride-potassium chloride was studied. Raw material of scandium oxide was reflux dissolved with concentrated hydrochloride acid, and the solution was mixed with sodium chloride, potassium chloride, and ammonium chloride solutions. Mixture solution was concentrated and evaporated under pressure condition in a flask, and then an aqueous mixture salt crystal produced was produced. After predehydration of aqueous mixture salt in vacuum drying cabinet, the last anhydrous molten salt was produced by heating and fusing under in quartz vessel in argon to dehydration completely and sublime ammonium chloride. According to the result of analysis, the content of water and insoluble scandium in molten salt is very little and is satisfied for preparation of crystal scandium and scandiumbearing master alloys by metallothermic reduction.