Optimization of Contact Time, Adsorbent Dosage, and Initial pH for Methylene Blue Removal in Aqueous Solution Using Citrus aurantium Peels

Proponent/s Name/s (Last Name, First Name, Middle Initial)

John Rich M. Adorna, De La Salle University - Laguna CampusFollow
Maria Carmela M. Lajara, De La Salle University - Laguna CampusFollow
Aldrin James F. Tolentino, De La Salle University - Laguna CampusFollow
Hiromi O. Yazaki, De La Salle University - Laguna CampusFollow

Document Type

Paper Presentation

Research Advisor (Last Name, First Name, Middle Initial)

Cabral, Kerry P.

Abstract/Executive Summary

The growing contamination caused by the dye and textile industries has generated serious environmental issues due to the release of chemically synthesized dyes such as methylene blue (MB), which are toxic and resistant to biodegradation. This study examines the impact of contact time, adsorbent dosage, and initial pH on the removal efficiency of MB using Citrus aurantium peels as a cost-effective and environmentally friendly adsorbent. The Box-Behnken design methodology was employed to identify optimal conditions for maximum removal. The research consisted of 15 experiments to determine the adsorption capacity under various conditions. Results showed that the removal efficiency was highest at 89.07% for a 60-minute contact time, indicating that an increased contact time allows a greater number of dye molecules to reach the binding sites of the DPAC surface. The best removal of dye was achieved under optimal conditions at a basic pH of 10, which increased the adsorption capacity through enhanced protonation of the adsorbent surface. The results highlight the capability of DPAC in wastewater treatment activities towards achieving sustainable development goals through agricultural residue valorization and enhancing water quality, revealing that both initial pH and contact time are the most significant parameters.

Keywords

activated carbon; adsorption; dalandan peels; methylene blue