Photocatalytic degradation of nonylphenol using nitrogen-doped carbon-based nanoparticles from calamansi peel waste/ Joraine B. Aragon, Ederwisa D. Cadigal, and Pia Monica M. Punzal.--

Bachelor's thesis

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

Includes bibliographic references and index.

Water pollution caused by nonylphenol, an endocrine-disrupting compound, poses
a serious environmental concern in several rivers in Metro Manila. This study evaluates
the photocatalytic degradation of nonylphenol using nitrogen-doped carbon-based

nanoparticles (NC-BNPs) from calamansi peel waste synthesized through the calcination-
to-reflux method. Various analytical instruments were used for the characterization of the

synthesized C-BNPs and NC-BNPs, such as a UV-Vis Spectrophotometer, a Fourier
Transform Infrared Spectrometer, a Scanning Electron Microscope and Energy Dispersive
X-ray Spectrometer, and a Spectrofluorophotometer. Results obtained from UV-Vis
analysis revealed that NC-BNPs possess enhanced optical properties compared to C-BNPs.
These findings were further validated by spectrofluorophotometer results, which displayed
broader emission peaks and higher fluorescence intensity for NC-BNPs. The successful
incorporation of nitrogen into the C-BNP matrix was confirmed through FTIR analysis,
where the presence of a peak at 3297 cm-1—attributed to a primary amide—indicated

nitrogen doping. SEM mapping and EDX Spectroscopy further verified the nitrogen-
doping as NC-BNPs contained nitrogen with 50.87% weight. Moreover, the morphology

and particle size distribution of the NC-BNPs were analyzed using SEM and ImageJ
version 1 software. The nanoparticles were of irregular shapes with non-uniform
morphology and had an approximate mean size of 15.3 nm with a standard deviation of
3.591, which indicated that there was a wider size distribution range of an integration of
small and large particles compared to the average size. Photocatalytic performance was
assessed under sunlight exposure, comparing control, C-BNPs, and NC-BNPs setups.
Results showed that nonylphenol with NC-BNPs achieved a significantly higher
degradation efficiency of 37.13% compared to 14.05% for C-BNPs. Optimization of
photocatalytic conditions revealed that pH 6, an initial nonylphenol concentration of 100
ppm, and 3 mL of NC-BNPs yielded the highest degradation rates. The study demonstrates
that NC-BNPs derived from agricultural waste present a sustainable and effective solution
for degrading harmful organic pollutants in water systems.