综合利用锂云母分解副产物硫酸钠制备碳酸氢钠的工艺探究

Preparation of NaHCO_3 Using a By-product of Na_2SO_4 from Decomposition of Lithium Mica

以硫酸(盐)法处理锂云母生产锂盐过程中的副产品硫酸钠为原料,利用结晶法制备高价值的碳酸氢钠,纯度高达90.77%;采用蒸发-冷却-再蒸发的方法回收副产物硫酸铵,每500 m L卤水可回收118.7 g固体,其中硫酸铵占39.6%。实现了变废为宝以及资源综合利用的目标。

Na_2SO_4,a by-product in the production process of lithium salt produced from lithium mica by sulfuric acid method,was taken as a raw material to prepare the valuable material of NaHCO_3 by crystallization,yielding the product with purity up to 90. 77%. The by-product of(NH_4)_2SO_4 was then recovered by the process of evaporation-coolingre-evaporation. It is found that 118. 7 g solid product with 39. 6%(NH_4)_2SO_4 can be recovered from 500 m L brine,achieving the goal of comprehensive utilization of resources by turning waste into valuables.