Adsorption of Methylene Blue from Aqueous Solutions Using Parkia speciosa Pod-based Magnetic Biochar

Abstract

This study was aimed to investigate the use of Parkia speciosa pod (petai pod) in the form of magnetic biochar as an efficient bioadsorbent to remove methylene blue (MB) in batch mode. The adsorption onto the magnetic biochar achieved about 99% of removal for all the initial concentrations studied (25 mg/L-250 mg/L). The adsorption processes were studied using the adsorption isotherms, which were analysed using Langmuir and Freundlich model. The adsorption using magnetic biochar followed Freundlich model, indicating the heterogeneous surface of the magnetic biochar. Thus, the study showed that the Parkia speciosa pod (PSP) as agricultural waste has the potential to be used as a low-cost adsorbent.