Production of Polyaluminum Ferric Chloride from Blast Furnace Dust

Our goal was to produce a complex inorganic polymer flocculant containing poly aluminum ferric chloride (PAFC) from blast furnace dust. The optimum reaction conditions to achieve high extraction efficiency of iron and aluminum were obtained through a series of batch experiments. PAFC was synthesized by controlling the hydrolysis conditions of iron and aluminum. Extraction efficiency of iron and aluminum oxides from blast furnace dust was affected greatly by reaction parameters such as temperature, time and hydrochloric acid consumption. The dissolution rate of iron was 67.61% and the dissolution rate of aluminum was 12.35% under the optimum reaction conditions (100 °C, 3 hours, and and the mixing ratio of the blast furnace dust to the hydrochloric acid is 1:3). To neutralize the pH and then synthesize PAFC, a solution of Al (OH)3 was added to the dissolved blast furnace dust, and the mixture was hydrolyzed at 60~70 °C for 4 hours. The prepared complex inorganic polymer flocculant proved to be effective in removing turbidity. The turbidity removal ratio for kaolin simulative water was 99.36%.