Preparation of As(Ⅲ) adsorbent material by electrolytic manganese slag and its properties

Abstract

As(Ⅲ) adsorbent (called modified EMRs) was prepared by modifying the industrial waste electrolytic manganese residues (EMRs). The effects of NaOH dosage, ultrasonic and microwave on its surface structure and adsorption performance were investigated. The results showed that most of the Si, S and Ca were removed by ultrasonic reaction (200 W) for 2 h with solid-liquid ratio M (EMRs):V(NaOH, aq) = 1:10 (C<inf>NaOH, aq</inf> = 2.0 mol•L^-1). Fe, Mn and other active adsorption groups were deposited on the surface after the microwave (700 W) was reacted for 5 min. Finally, the adsorbent dried at 105℃. The SEM results show that the surface of the material has a lamellar nanostructure and good adsorption performance for arsenic. The initial As(Ⅲ) concentration of 50 mg•L^-1 wastewater effluent can be reduced to 0.042 mg•L^-1. The national surface water environmental quality standard Class I water quality requirements (GB 3838-2002), at the same time, can be continued after being regenerated by 3% NaOH solution. XPS results show that the adsorption of arsenic by modified EMRs is closely related to the increase of active species such as Fe<inf>3</inf>O<inf>4</inf>, FeOOH and MnO<inf>2</inf> on As(Ⅲ) adsorption or oxidation.