Sodium Hydroxide Activated Nanoporous Carbons Based on Lapsi Seed Stone

Area of Science:

• Materials Science
• Chemical Engineering
• Environmental Science

Background:

• Activated carbons (ACs) are widely used adsorbents.
• Developing sustainable and cost-effective ACs from biomass is crucial.
• Lapsi (Choerospondias axillaris) seeds represent an underutilized biomass source.

Purpose of the Study:

• To synthesize nanoporous activated carbons from Lapsi seed powder.
• To investigate the effect of sodium hydroxide (NaOH) impregnation ratio on AC properties.
• To evaluate the methylene blue adsorption performance of the synthesized ACs.

Main Methods:

• Chemical activation of Lapsi seed powder with NaOH at varying ratios.
• Characterization using FTIR, Raman spectroscopy, XRD, and SEM.
• Evaluation of surface properties via iodine number, BET surface area, and nitrogen adsorption-desorption isotherms.
• Methylene blue adsorption capacity measurement.

Main Results:

• FTIR confirmed the presence of oxygenated functional groups.
• Raman spectroscopy indicated a decrease in graphitic degree with increasing NaOH ratio.
• XRD patterns revealed an amorphous structure.
• Synthesized ACs exhibited a high methylene blue adsorption capacity (up to ~200 mg/g).

Conclusions:

• The NaOH impregnation ratio is a critical parameter for tailoring the surface properties of Lapsi seed-based ACs.
• Optimizing NaOH ratio can enhance adsorption capabilities for pollutants.
• Lapsi seed powder is a promising precursor for producing functional activated carbons.