Preparation and characterization of activated carbon from groundnut and egg shells as viable precursors for adsorption

Abstract

This study was carried out to prepare groundnut shell (GS) and eggshell (ES) into activated carbon (AC) and characterize the AC using Association of Official Analytical Chemists (AOAC) and American Standard for Testing and Materials (ASTM) methods. The AC produced was characterized for: pH, moisture content, volatile matter, ash content, fixed carbon, bulk density and surface area. Surface functional groups and surface morphology were also determined using Fourier Transformed Infrared (FT-IR) and Scanning Electron Microscope (SEM) respectively. The ranges of the following results were achieved for the biomasses: Groundnut shell Activated Carbon (GSAC) and Eggshell Activated Carbon (ESAC) respectively: pH (6.80±0.101−7.80±0.011); moisture content (14.10±0.101−12.90±.110%); volatile matter (9.20±0.112−9.90±0.012%); ash content (8.98±0.111−5.80±0.111%); fixed carbon (67.70±0.010−71.40±110%); bulk density (370.00±0.000−380.00−0.000 g/L); surface area (880.00±0.100−800.00±0.000 m2/g). The agro-wastes have high carbon contents and low inorganic which make them viable adsorbents. FT-IR analysis revealed the presence of oxygen surface complexes such as carbonyls and OH groups on the surface of the ACs in addition to good pore structures from SEM studies revealed that the agro-wastes could be good precursors for ACs production. The overall results showed that the AC produced from the agro-wastes can be optimally used as good and effective adsorbents, thereby ensuring cheaper, readily available and affordable ACs for the treatment of effluent, waste water and used oils.

Keywords

• Agro-wastes, activated carbon, adsorbents, biomasses, FT-IR, SEM, adsorption