Abstract: Battery-grade ferrous oxalate was prepared with the by-product ferrous sulfate from titanium white production as raw material.Influences of reaction temperature，reaction time，concentration of ferrous sulfate，and pH etc. in the processes of impurity removal，precipitation，and conversion reaction on the product quality were discussed，and the optimum process conditions were obtained.Results showed that battery-grade ferrous oxalate with particle size less than 3.0 μm，purity more than 99.5%，and with low impurity content could be prepared under the conditions as follows：pure ferrous sulfate solution was obtained by using iron powder to purify it at the reaction temperature of 95 ℃ for 6 h；then use ammonia to precipitate ferrous sulfate at the reaction temperature of 40 ℃ and Fe²⁺ mass concentration of 90 g/L；at last，use oxalate to converse the ferrous hydroxide into ferrous oxalate at the reaction pH=2.0 and time of 60 min.Thus，an effective way was provided to utilize the by-product of titanium white.

Key words: ferrous oxalate, ferrous sulfate, battery