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

Sustainable processing of methylene blue dye-adsorbed Zea mays peel ash biosorbent as a novel heterogeneous catalyst for biodiesel production

Akshay Prakash and Jerold Manuel

Department of Biotechnology, National Institute of Technology Warangal, Warangal, India

E-mail: jerold@nitw.ac.in

Received: 9 July 2024  Accepted: 6 March 2025

Abstract:

This study investigates the circular economy approach of Zea mays peel ash as an adsorbent for methylene blue (MB) dye and as a sustainable renewable heterogeneous green catalyst for the transesterification of waste cooking oil into biodiesel. The adsorption study shows that MB removal was maximum at pH 8 with 89.95% in 60 min. The functional groups and surface morphology of Zea mays peel ash were analysed using FTIR and SEM, respectively. The spent Zea mays peel dye-adsorbed ash was valorized into green catalyst by calcination process at 400 °C for 60 min. The optimization of transesterification reactions is achieved using the Taguchi method. A maximum yield of 95.77% FAME (fatty acid methyl ester) obtained at reaction time (240 min), temperature (65 °C), catalyst load (1.5 wt.%), and methanol-to-oil ratio (4:1). The FAME was purified and characterized through various analyses, including gas chromatography and nuclear magnetic resonance. Overall, this study shows that Zea mays peel ash can used as a promising biosorbent for dye sequestration and a sustainable catalyst for biodiesel production.

Graphical abstract

Keywords: Biodiesel; Biomethanol; Crop waste; Materials for Energy and Catalysis; Zeolites; Zea mays; Zea mays peel ash; Methylene blue; Adsorbent; Catalyst; Biodiesel; Optimization

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-025-04083-8

Chemical Papers 79 (8) 4925–4942 (2025)