以往,在锂云母-石灰石烧结法生产锂盐的过程中,氧化钙的测定是在pH=12时,用钙指示剂EDTA滴定法。然而物料中所含氟及锂等,使终点变化不敏锐,测定结果不稳,不能正确地指导生产。为解决这一矛盾,我们改用钙黄绿素-酚酞指示剂,待测溶液中氟量达50毫克也不干扰。原方法酸溶样后需沉淀 In the past, lithium oxide in the production of lithium-limestone limestone process, the determination of calcium oxide at pH = 12, the use of calcium EDTA titration method. However, the material contained in fluorine and lithium, the end point change is not sharp, the measurement results are not stable, can not correctly guide the production. To solve this contradiction, we use calcein - phenolphthalein indicator, the test solution of fluorine content of 50 mg does not interfere. The original method of acid precipitation after precipitation