Method for preparing anhydrous ferric phosphate by using spent pickling solution of iron and steel works

• Main Authors: ZENG XIANQIN, YE MING, LIAO CUI, HU YU, PENG AIPING, XIE JUN, MA MULIN, XIE XIAOLIN, LI LIANGBIN, HU ZHIHUA, LI FANGFANG
• Format: Patent
• Language: Chinese; English
• Published: 12.07.2019
• Subjects: CHEMISTRY; COMPOUNDS THEREOF; INORGANIC CHEMISTRY; METALLURGY; NON-METALLIC ELEMENTS

The invention discloses a method for preparing anhydrous ferric phosphate by using a spent pickling solution of iron and steel works. The method comprises the following steps: (1) concentrating, cooling and recrystallizing impurity removal; (2) crude preparation of ferric phosphate; (3) redissolving of ferric phosphate; and (4) secondary preparation of ferric phosphate. The anhydrous ferric phosphate is prepared through removing a majority of impurity ions by adopting a concentrating and recrystallization method according to differences of solubility, then, synthesizing ferric phosphate at a relatively low pH to further remove relatively-difficult-removed ions such as Zn, Cr and Mn ions, then, redissolving the ferric phosphate with acid, and carrying out secondary preparation on ferric phosphate. By adopting the above-mentioned steps, wastewater of pickling works can be recycled, and the prepared anhydrous ferric phosphate is low in impurity content and has a primary particle size of 100nm or less. 本发明公布了一种利用