Synthesis and characterization of microporous granular activated carbon from Silver berry seeds using ZnCl₂ activation

Abstract

Granular activated carbon (GAC) was synthesized from Silver berry (Elaeagnus Angustifolia L.) seeds using zinc chloride as the activation agent. To optimize the operating parameters, the effects of the time and temperature of carbonization, impregnation ratio, and heating rate on the iodine number and yield of activated carbon were studied. Optimized parameters were impregnation ratio of 1:1, carbonization temperature of 500 °C, carbonization time of 1 hour, and heating rate of 5 °C/min. The GAC synthesized under optimized conditions was characterized by Nitrogen adsorption-desorption isotherms, SEM, EDX, XRD, FT-IR, Boehm titration, TG-TGA, and TG-IR. It was found that the synthesized GAC has a microporous structure with a BET surface area of 1109 m²/g, a micropores volume of 0.317 cm³/g, and an average pore diameter of 2.1 nm. The methylene blue (MB) dye was employed as a molecule model to evaluate the porosity and the adsorption capacity of the synthesized GAC. The results showed that the maximum adsorption capacity of MB and the percent portion of the surface area (S_MB/S_BET) were 120.48 mg/g and 30.62%, respectively. The experimental results reveal that the synthesized GAC can be used as a low-cost adsorbent for the removal of small and large environmental pollutants.

Keywords:

• Granular activated carbon
• Elaeagnus Angustifolia seeds
• ZnCl₂
• chemical activation
• thermogravimetric analysis

Acknowledgment

The authors acknowledge the Department of Chemistry, University of Batna 1, LCCE Laboratory for rendering the facilities during this research.