Synthesis of Cancrinite Zeolite From Toraja Natural Bentonite for Heavy Metal Removal From Wastewater

Open

Yuli Astuti, Paulina Taba, St Fauziah, Syarifuddin Liong, Yusafir Hala, Nur U. Permatasari, Satria P.J. Negara, Fadliah

2025 Karbala International Journal of Modern Science Vol. 11 Issue 3 Article Cited by 0 Quartile

Abstract

This study explores the production of cancrinite (CAN) zeolite from bentonite found in Toraja (a place in South Sulawesi Province, Indonesia) and its effectiveness in removing Pb2þ and Fe3þ ions from wastewater. The synthesis was carried out using a hydrothermal method with varying NaOH concentrations, where a single phase of zeolite was formed at 5 M, as confirmed through XRD analysis. FTIR results showed the characteristics of CAN zeolite with typical absorption peaks at 676, 622, and 565 cm¡1, as well as the presence of carbonate groups (CO32¡) at 1300-1400 cm¡1. SEM analysis revealed thin columnar needle-like crystals characteristic of CAN zeolite. Nitrogen adsorptionedesorption tests revealed that CAN zeolite is mesoporous with an average pore size of 5.38 nm and a specific surface area of 51.97 m2/g. The optimal conditions for Pb2þ adsorption were achieved with a contact time of 180 min and a pH of 5, while for Fe3þ, the optimal conditions were a contact time of 30 min and a pH of 3. The adsorption isotherm was evaluated using Langmuir, Freundlich, and Sips models, with the best described by the Sips model in non-linear fitting. The maximum adsorption capacities for Pb2þ and Fe3þ ions were 194.95 mg/g and 196.63 mg/g, respectively. The adsorption kinetics for both ions followed a pseudo-second-order kinetic model. This study reports about natural Toraja bentonite, a rarely explored precursor for CAN zeolite synthesis. It also assesses the zeolite's adsorption capacity for two metal ions of different valences, highlighting its potential in wastewater treatment. © 2025 University of Kerbala.

Affiliations

Department of Chemistry, Hasanuddin University, Makassar, Indonesia; Department of Chemistry, State University of Makassar, Makassar, Indonesia; Department of Mining Engineering, Trisakti University, Jakarta, Indonesia