Method for removing potassium from mother liquor in lithium hydroxide production

The invention provides a method for removing potassium from mother liquor in lithium hydroxide production. The method comprises the following steps: S1, adding sulfuric acid into the lithium hydroxide separation mother liquor for acidification; s2, heating the mother liquor obtained by acidification in the step S1, and supplementing sodium sulfate; s3, freezing and crystallizing the mother liquor obtained in the step S2, and filtering and separating solids and a sodium precipitation solution; and S4, returning the obtained sodium precipitation solution to a lithium hydroxide production system. The method is suitable for a low-cost and short-process potassium removal process for lithium hydroxide production, the potassium removal rate is greater than or equal to 50%, and the potassium content in a lithium hydroxide system can be effectively reduced. 本发明提供一种氢氧化锂生产母液除钾的方法。方法包括以下步骤：步骤S1：氢氧化锂分离母液加入硫酸酸化；步骤S2：加热所述步骤S1酸化所得母液后，补加硫酸钠；步骤S3：将所述步骤S2所得母液冷冻析晶，过滤分离固体和析钠溶液；步骤S4：所得析钠溶液返回氢氧化锂生产系统。本发明适合氢氧化锂生产的低成本、短流程除钾工艺，除钾率≥50%