(Special session) Powder and Purification Engineering Division Committee "Student Award Session”

[1K0306-15-09] [Student presentation: Doctoral course] Selective adsorption of arsenic ions from copper wastewater by carboxylic acid/layered double hydroxides

○Yusuf Olalekan Zubair¹, Mauricio Córdova-Udaeta¹, Shigeshi Fuchida¹, Chiharu Tokoro^1,2 (1. Waseda University, 2. The University of Tokyo)

司会：晴山　渉（岩手大学）

Keywords: Copper wastewater, Selective adsorption, Arsenic species, R-CO2H/LDHs

Mining of copper related minerals had resulted in the release of arsenic species into our immediate environment and excessive exposure to it has detrimental effects on human organ systems. Several materials have been investigated for arsenic sequestration but most of these materials exhibit poor performance for arsenic uptake in the presence of foreign ions. Herein, we utilized carboxylic acid (R-CO₂H) to enhance the adsorptive properties of layered double hydroxides (LDHs) using a hybrid approach; namely, coprecipitation and hydrothermal methods. The results obtained showed that the addition of R-CO₂H enhanced the surface area of the LDH by more than 40%, indicating that the functionalized LDHs can selectively adsorb more arsenic from wastewater containing large amounts of copper. The copper wastewater contained 2.01 mg/L As, 366 mg/L Cu, 20.1 mg/L Zn, 0.12 mg/L Cd, and 4600 mg/L SO₄^2- with initial pH value of 2. Thus, the selective removal of poisonous elements such as arsenic ions could lead to the valorization of copper and zinc in the wastewater via a ferritization process.