Biosorption and kinetic studies of Malachite Green (MG) dye removal from aqueous solution using a low-cost adsorbent prepared from male palm tree flower (Borassus flabellifer)

摘要

Activated carbon derived from male palm tree flower (MPTF) (Borassus flabellifer) was used as adsorbent to adsorb Malachite Green (MG) dye. Batch adsorption studies were performed by varying the parameters like initial solution pH, adsorbent dosage, initial dye concentration and temperature with activated carbon prepared from MPTF. The maximum dye removal ( 95%) was occurred at an optimum pH of 6.0, and zero point charge was found to be 2.75. Isotherm models such as Langmuir, Freundlich, and Temkin were used to analyse the experimental data, and it was found that the Langmuir isotherm model was best fitted with the adsorption data. Further, the separation factor (R-L) value was less than unity indicating a favourable adsorption process. Thermodynamic parameters such as Delta G, Delta H, and Delta S were calculated for the adsorption processes and indicate that the adsorption process was spontaneous and endothermic in nature. Adsorption rate constants were determined using pseudo-first-order, pseudo-second-order rate equations, and also Elovich model and intraparticle diffusion models. The results clearly showed that the adsorption of MG followed pseudo-second-order model, and the adsorption was controlled by intraparticle diffusion.