This work was carried out to prepare and characterize adsorbents from clay and coconut shell. Two clay samples, uncalcinated activated clay (UAC) and calcinated activated clay (CAC), and one coconut shell sample, activated coconut shell carbon (ACC), were prepared. One of the clay samples was simply oven-dried at 105 °C while the other was calcined at 600 °C and the coconut shell was carbonised in a muffle furnace. The three samples were chemically activated to obtain ACC, UAC and CAC needed for the characterisation. The physicochemical and adsorptive properties were investigated for the adsorbents. The adsorbents were also characterized by FTIR (to identify the bonding present), BET (to obtain the specific surface areas and pore volumes and sizes) and SEM (to study the surface morphologies) of the adsorbents. CAC was found to have the highest value cation exchange capacity (CEC) of 2.114. This means it retained more cations on the particle surfaces and hence could be better adsorbent for cationic pollutants. The presence of O-H vibration peaks in the FTIR spectra of both CAC and UAC samples indicated that the calcination or activation process did not affect the hydrogen bonding. The SEM analysis shows that interconnected granular micro-porosity was observed in the activated carbon sample, favoring their effectiveness as catalysts. From the BET analysis, CAC has the highest specific surface area, 235.5 g/m2, which shows it could have the best adsorption capacity. It can also be deduced from the pore diameters that the three adsorbents prepared are mesoporous. The three samples showed good adsorptive properties, hence can be used to remove liquid or gaseous pollutants.
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