Clean and efficient synthesis of LiFePO4 cathode material using titanium white waste and calcium dihydrogen phosphate.

[Display omitted] • Titanium white waste was used as the iron source to prepare LiFePO 4 cathode material. • The feasibility of whole process was verified by thermodynamic analysis. • The contents of impurities in the product were far below the standard. • The electrochemical performance of the synthesized LiFePO 4 was satisfactory. Large amounts of titanium white waste are generated in the production of titanium dioxide using sulphate method, which in turn can be used to prepare LiFePO 4 cathode material, thereby reducing environmental risks and achieving resource recovery. However, a key challenge lies in the elimination of impurities. In this work, a cost-efficient and straightforward approach based on phase transformation during hydrothermal treatment was proposed to utilize titanium white waste with calcium dihydrogen phosphate for the preparation of LiFePO 4 cathode material. The content of Fe in the leachate was enriched to 81.5 g/L after purification, while 99.9 % of Ti and 98.36 % of Al and were successfully removed. In the subsequent process for Fe/P mother liquor preparation, the losses of Fe and P were only 5.82 % and 2.81 %, respectively. The Fe and P contents of the synthesized FePO 4 product were 29.47 % and 17.08 %, respectively, and the Fe/P molar ratio was 0.986. Crystal phase of the product matched well with standard iron phosphate, and the lamellar microstructure of FePO 4 was uniform with the particle size ranging from 3 to 5 μm. Moreover, the contents of impurities in the product were far below the standard. The initial discharge of LiFePO 4 synthesized by the iron phosphate was 160.6 mAh.g−1 at 0.1C and maintained good reversible capacity after 100 cycles. This work may provide new strategy for preparing LiFePO 4 cathode material from industrial solid waste. [ABSTRACT FROM AUTHOR]