The recycling of ferric salt in steel pickling liquors: preparation of nano-sized iron oxide

摘要

A novel process of recycling ferric salt in Steel Spent Pickling Liquors (SPL) is reported in this paper which refers to the combination of vacuum evaporation and preparation of nano-sized iron oxide (α-Fe2O3) by precipitation method. This study investigates the effect of ammonia concentration, Fe~(2+) concentration, reaction temperature, stirring speed and calcine temperature on the preparation of α-Fe2O3 by single factor experiment and the optimal preparation conditions of preparing α-Fe2O3 by orthogonal experiment. The results show that the concentration of Fe2O3 in product is up to 98.87%, and the average crystal diameter is about 31.3nm under optimized technological conditions, which realized the highest recycling rate of Fe at 85.6%.