Effect of Preparation Conditions on Heavy Metal Adsorption Characteristics of Activated Carbon Prepared from Non-Fibrous Material of Pineapple Leaves

Abstract

Activated carbon can be prepared from any kind of hydrocarbon-based material, and that from agricultural wastes is attractive for many reasons. The use of natural fiber in various industries gives rise to some associated waste streams. In this work, activated carbon, produced from the non-fibrous material waste from pineapple leaf fiber production, was studied for its heavy metal adsorption behavior. The material was carbonized at different temperatures and chemical activation was carried out using phosphoric acid. Pore size and pore volume of the adsorbent were determined using the Brunauer–Emmett–Teller (BET) method, and surface morphology by scanning electron microscopy (SEM). Fourier Transform Infrared Spectrophotometry (FT-IR) was used to identify the functional groups in the material. It was found that the surface area, pore volume and morphology of the surface depended on the carbonization temperature. The best adsorbent was obtained using a carbonization temperature of 500 °C and an activation temperature of 600 °C. Adsorptions of several heavy metals were studied over the concentration range of 4 - 800 mg L−1 and pH 2-10. The optimum amount of the adsorbent was found to be 1.20 g per 100 ml of solution, removing up to 92.67% of lead ions. The adsorption behaviour was closer to the Freundlich isotherm than to the Langmuir isotherm. So this waste could be a useful bio-source for activated carbon production.