High‐efficiency preparation of Fe–Al based flocculants from red mud by microwave selective carbothermic reduction and magnetic separation

Abstract

AbstractFe–Al based flocculants (PAFC) have been widely used in sewage treatment. In this article, a new method for preparing PAFC from red mud was proposed, the magnetic product was upgraded and “downgrading Fe of red mud” was obtained based on a microwave selective carbothermic reduction and magnetic separation technique. The results showed that the Fe and Al contents in “downgrading Fe of red mud” were determined to be 24.60% and 22.27%, respectively. The Fe and Al digestion rates of “downgrading Fe of red mud” were 81.24% and 28.55% during the preparation of PAFC, respectively. The prepared PAFC can effectively achieve the effect of sewage treatment, and the turbidity removal rate of sewage reached 88.17%. In addition, microwave can realize rapid reduction at low temperature, and the magnetite obtained by magnetic separation can be used in the iron‐making process to realize the recycling of resources.