ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Integrated kinetic and neural network modeling of Cd(II) adsorption using biopolymeric beads derived from agro-waste

R. V. Hemavathy, R. Kamalesh, A. Saravanan, P. R. Yaashikaa, and A. S. Vickram

Department of Biotechnology, Faculty of Engineering and Technology, SRM Institute of Science and Technology, Chennai, India

E-mail: sara.biotech7@gmail.com

Received: 27 June 2025  Accepted: 26 August 2025

Abstract:

The environmental contamination through heavy metals has been considered to be a serious concern among researchers due to its far-reaching impact toward the environment. Among other heavy metals, cadmium in water is considered a perilous environmental challenge due to its persistence and toxicity, necessitating a cost-effective remediation approach. The adsorption of cadmium using cellulose-based biopolymeric beads was investigated in the current study. The cellulose has been derived from rich husk; a promising source of natural polymer due to its chemical composition. This study integrated both the batch adsorption studies and artificial neural network (ANN) for enhanced prediction and accuracy. The structural and chemical behavior of the prepared biosorbent has been characterized through SEM, FTIR, and EDX analysis. The optimum parameters identified from the batch studies include pH = 6.0, adsorbent dosage = 2.5 g/L, contact time = 50 min, temperature = 303 K, and initial cadmium concentration = 1 mg/L. The Langmuir model is the best fit with a q_e of 154.24 mg/g, while kinetic studies specified pseudo-second order with an R² value of 0.9688. The thermodynamic study revealed that the process is exothermic and spontaneous. The ANN model has demonstrated strong prediction accuracy with an R² of 0.9941. The study revealed a higher desorption capacity of 94.57% for HNO₃. The regeneration study states that the adsorption–desorption efficiency has declined after the 4th cycle. These findings highlight rice husk as an efficient and sustainable source for cadmium removal, presenting a solution for addressing heavy metal pollution in wastewater treatment.

Graphical abstract

Keywords: Cadmium; Rice husk; Biosorbent; Adsorption; Desorption

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-025-04355-3

Chemical Papers 79 (12) 8843–8861 (2025)