Chitosan-functionalized activated biochar from pomelo peel waste for methyl orange dye removal/ Nicole C. Agullo, Mitzi B. Laxamana, and Loiza Mae A. Panoy.--

Bachelor's thesis

College of Science.--
Bachelor of applied science in laboratory technology: Technological University of the Philippines,
2025.

Includes bibliographic references and index.

This study aimed to develop chitosan-functionalized activated biochar (FPPAB)
from pomelo peel waste for the removal of Methyl Orange (MO) dye from aqueous
solutions. It sought to synthesize FPPAB through phosphoric acid activation, pyrolysis,
and chitosan coating; evaluate its performance against unmodified and activated biochar;
optimize key adsorption parameters; characterize the material; and identify the
applicable adsorption kinetics and isotherm models. The biochar was characterized
using FTIR, SEM, and EDX, confirming successful functionalization and surface
modification. Batch adsorption experiments were conducted to assess the effects of
contact time, initial concentration, pH, and temperature, with UV-Vis spectrophotometry
used to measure dye removal. FPPAB achieved a maximum removal efficiency of
98.97% under optimal conditions: 0.1 g dosage, 25 minutes contact time, 90 ppm
concentration, and pH 3 at 50°C. The process followed pseudo-second-order kinetics (R2
= 0.9999) and aligned with the Freundlich isotherm model (R2 = 0.8942). The findings
highlight FPPAB as a promising, eco-friendly adsorbent for wastewater treatment.