Synthesis of Stabilized Iron Nanoparticles from Acid Mine Drainage and Rooibos Tea for Application as a Fenton-like Catalyst

Elyse Kimpiab; Kashala Fabrice Kapiamba; Leo Folifac; Oluwaseun Oyekola; Leslie Petrik

doi:10.1021/acsomega.2c01846

Synthesis of Stabilized Iron Nanoparticles from Acid Mine Drainage and Rooibos Tea for Application as a Fenton-like Catalyst

ACS Omega. 2022 Jul 6;7(28):24423-24431. doi: 10.1021/acsomega.2c01846. eCollection 2022 Jul 19.

Authors

Elyse Kimpiab¹, Kashala Fabrice Kapiamba², Leo Folifac¹, Oluwaseun Oyekola¹, Leslie Petrik³

Affiliations

¹ Department of Chemical Engineering, Cape Peninsula University of Technology, Symphony way, P.O. Box 1906, Bellville, Cape Town 7535, South Africa.
² Department of Civil, Architectural and Environmental Engineering, Missouri University of Science and Technology, Rolla, Missouri 65401, United States.
³ Environmental and Nanoscience, Chemistry Department, Faculty of Natural Science, University of the Western Cape, Cape Town 8000, South Africa.

Abstract

Intensive mining activities generate toxic acid mine drainage (AMD) effluents containing a high concentration of metals, including iron. The chemical synthesis of iron nanoparticles from this waste could lead to further environmental concerns. Therefore, the green synthesis of nanoparticles using plants has gained significant interest because of several benefits, including being eco-friendly. The current study reports a novel approach involving the synthesis of stabilized iron nanoparticles from AMD using rooibos tea extract. An aqueous solution of rooibos tea was prepared and titrated with AMD to reduce Fe²⁺/Fe³⁺. The samples synthesized under optimum conditions were characterized by TEM, XRD, FTIR, UV-Vis, and EDS. The results revealed that the nanoparticles had an average particle size of 36 nm with a spherical shape. These particles showed promising application as a Fenton-like catalyst for the degradation of textile dye (orange II sodium salt) with a removal efficiency of 94% within 30 min. Thus, the stabilized iron nanoparticles synthesized here performed in higher ranges than the currently reported Fenton-like catalysts regarding dye removal efficiency and reaction time.