Abstract: For the purpose of improving the purity of the by-product calcium chloride of soda ash production，the purification experiments were studied through adopting various impurity removal methods，such as filtering, recrystallization，adding calcium oxide，and clinoptilolite adsorption.Results showed that the content of CaCl₂ was increased by 7.3%（mass fraction，same as below），the contents of NaCl，MgCl₂，and Fe was reduced by 52%，84%，and 98%，respectively，on the basis of purification of industrial grade calcium chloride；furthermore，Pb and Cu were also removed.The indexes, such as CaCl₂，NaCl，MgCl₂，water insoluble，Pb，Fe，and Cu of the final product all met the requirements of food grade calcium chloride.

Key words: calcium chloride, purification, calcium oxide, recrystallization, adsorption