Removal of Rhodamine B from Aqueous Solution Using Palm Shell-Based Activated Carbon: Adsorption and Kinetic Studies

Abstract

Palm shell derived activated carbon was utilized as a potential adsorbent to remove rhodamine B (RB) from aqueous solution. Activated carbon was prepared from palm shell through a physiochemical activation process to yield a sample with a Brunauer−Emmett−Teller (BET) surface area of 476.8 m2·g−1. The ability of the prepared activated carbon for dye adsorption was examined in a series of batch experiments. The effect of various process parameters such as initial dye concentration [(41.8 to 208.8) μmol·L−1], solution pH (3 to 11), and temperature [(30 to 50) °C] on the adsorption capacity of the adsorbent was investigated. Various adsorption isotherms (Langmuir, Freundlich, and Temkin) were used to interpret the experimental data. The obtained sorption data were reasonably described by the Langmuir model. The Temkin isotherm confirmed the presence of a repulsive lateral interaction in the adsorbent surface. Pseudofirst- and second-order kinetic models were used to predict the kinetics of the adsorption process. The obtained results revealed that the adsorption of RB on activated carbon followed a pseudosecond-order kinetic model. A maximum dye removal efficiency of 95 % was achieved at an initial dye concentration of 62.6 μmol·L−1, pH of 3, and temperature of 50 °C.