Work

Synthesis of palm kernel shells-biochar adsorbent for removal of methylene blue and then reused for latent fingerprint detection using spent adsorbent

Year: 2025

Type: article

Abstract: According to this study, palm kernel shells-biochar (PKS-BC) adsorbent was prepared for the purpose of removing methylene blue (MB) dye and reusing the spent adsorbent in latent fingerprint detection. Brunauer-Emmett-Teller (BET) surface area analysis, Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), zeta potential analysis, and X-ray diffraction (XRD) patterns were used to characterize this PKS-BC adsorbent. The PKS-BC adsorbent demonstrated a miro-mesoporous structure with a surface area of 586.187 m2/g, according to the experimental data. With a maximum adsorption capacity of 263.16 mg/g, an optimum dosage of 50 mg, dye concentration of 10 mg/L, and pH of 6.5 as neutral water for 180 minutes of room temperature, this adsorbent has demonstrated that it is the superior adsorbent for removing MB dye. The adsorption of MB dye on PKS-BC adsorbent was best suited by the Freundlich model and pseudo-second-order kinetics, suggesting that a multi-step nature of the adsorption process and surface complexation were the primary influencing factors. Additionally, the thermodynamic study revealed that the MB dye adsorption on the PKS-BC adsorbent was exothermic, with negative ΔH and ΔGo values (spontaneous adsorption process). Additionally, MB loaded on PKS-BC (MB-PKS-BC) spent adsorbent was reused as superior fingerprint powder with the powder dusting approach for the detection of latent fingerprints (LFPs). Under daylight conditions, this spent adsorbent MB-PKS-BC clearly displayed ridge patterns and LFPs images on a variety of surfaces, including glass slides, aluminum foil, aluminum sheets, and tiles. Aged LFP images were also examined for 5 to 20 days on an aluminum foil substrate. These findings suggest that PKS-BC adsorbent holds promise for the removal of MB dye from wastewater and for the reuse in LFPs detection for criminal identifications using the MB-PKS-BC spent adsorbent.

Source: Green Analytical Chemistry

DOI: 10.1016/j.greeac.2025.100259

Authors: Eswaran Prabakaran, Kriveshini Pillay

Institution: University of Johannesburg

Language: English

Topic: Adsorption and biosorption for pollutant removal

Subfield: Water Science and Technology

Field: Environmental Science

Domain: Physical Sciences

SDG: Responsible consumption and production

Open Access status: gold

Estimated APC paid: $1,550