Eco-Friendly Activation of Fe₂O₃/GSBA-15 Using Tamarindus indica Pulp Extract for Enhanced Adsorptive Removal of Methylene Blue and Methyl Orange from Contaminated Water

Maria Ulfa (Chemistry Education Study Program, Faculty of Teacher Training and Education, Sebelas Maret University, Jl. Ir. Sutami 36A Surakarta 57126)
Youlanda Jesiva Alba (Chemistry Education Study Program, Faculty of Teacher Training and Education, Sebelas Maret University, Jl. Ir. Sutami 36A Surakarta 57126)
Nurma Yunita Indriyanti (Chemistry Education Study Program, Faculty of Teacher Training and Education, Sebelas Maret University, Jl. Ir. Sutami 36A Surakarta 57126)
Nanik Dwi Nurhayati (Chemistry Education Study Program, Faculty of Teacher Training and Education, Sebelas Maret University, Jl. Ir. Sutami 36A Surakarta 57126)
Agung C. Saputro (Chemistry Education Study Program, Faculty of Teacher Training and Education, Sebelas Maret University, Jl. Ir. Sutami 36A Surakarta 57126)

Bulletin of Chemical Reaction Engineering & Catalysis
2026: BCREC Volume 21 Issue 4 Year 2026 (December 2026) (Issue in Progress)

In this study, a sustainable mesoporous silica material was synthesized using gelatin as a co-template (GSBA-15), followed by the incorporation of iron oxide (Fe₂O₃) to enhance its adsorption performance toward methylene blue (MB) and methyl orange (MO). Tamarindus indica pulp extract (TIE) was employed as a natural and environmentally benign activating agent, providing organic functionalities that facilitated material synthesis and surface modification. The adsorption performance of the synthesized materials, namely GSBA-15 and Fe₂O₃/GSBA-15-TIE, was evaluated using UV–Vis spectrophotometry. Under optimal adsorption conditions, the maximum adsorption capacities for MB were 176.062 and 183.497 mg.g⁻¹ for GSBA-15 and Fe₂O₃/GSBA-15-TIE, respectively. For MO, the corresponding adsorption capacities were 15.582 and 16.000 mg.g⁻¹. Kinetic studies revealed that the adsorption of both dyes was best described by the pseudo-second-order model, suggesting that chemisorption played a dominant role in the adsorption process. The enhanced adsorption performance of Fe₂O₃/GSBA-15-TIE compared with pristine GSBA-15 demonstrates the beneficial effects of iron oxide incorporation and TIE activation. These findings highlight the potential of Fe₂O₃/GSBA-15-TIE as a sustainable and efficient adsorbent for dye removal in wastewater treatment applications. Copyright © 2026 by Authors, Published by BCREC Publishing Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).