Adsorptive findings on selected biomasses for removal of phenol from aqueous solutions

Abstract

India produces an enormous number of biomasses in the form of agricultural and forestry residues. To handle their disposal, they need to be explored as adsorbents, as one of the alternatives for their utilizations. Biomasses, having a high content of carbon, can be used as low-cost adsorptive materials for the removal of phenol from aqueous streams. Ten biomasses, abundantly available in the Sangrur area of Punjab (India), were characterized. Based on their determined characteristics and availability, Acacia nilotica branches (ANB), Lantana camera (LC), and rice husk (RH) were selected for the study. As these biomasses removed low percentages of phenol, they were activated using thermochemical treatment. Their properties as adsorbents improved significantly. When they were subjected to phenol sequestration, the percentage removal of adsorbate was at 97%, 90%, and 83% by activated ANB (ANBC), activated LC (LCC), and activated RH (RHC), respectively. The equilibrium and kinetics of the process of adsorption on these activated biomasses were analyzed mathematically. It was possible to regenerate the spent ANBC, LCC, and RHC in a single step, with 1MNaOH solution.