Adsorption of Methylene Blue and Eriochrome Black T using Biochar Derived from Hyphaene thebaica Shell: A Comprehensive Kinetic, Isotherm and Thermodynamic Study

This work aimed to develop an adsorbent; biochar (HTBC) from Hyphaene thebaica shell. The biochar was characterized using FTIR and SEM. The FTIR and EDX results show the surface of HTBC adsorbent was rich in functional group such as (-C=C, C≡C (aromatic ring), -C-O and -C≡N) and the morphology show heterogenous compacted porous structures which can be attributed to the volatilization of cellulose, hemicellulose, and lignin materials during the pyrolysis process of the biochar which makes it possible to obtain a more organised structure. The adsorbent was examined to access the influence of various parameters such as time, dosage, solution pH and initial dye concentration for adsorption of methylene blue (MB) and Erichrome black T (EBT) from aqueous solution. Adsorption models and kinetics show that EBT and MB adsorption fitted Freundlich for HTBC adsorbent. The maximum adsorption capacity (Qmax) for MB (20.2mg/g) which was dosage dependent at 0.2g and EBT (25.5mg/g) was pH dependent at (pH 2). Adsorption of EBT and MB onto HTBC and MFBC followed pseudo-second order kinetics. While thermodynamic studies show adsorption of EBT and MB onto HTBC was spontaneous and thermodynamically feasible.