Efficient cadmium removal from industrial phosphoric acid using banana pseudostem-derived biochar

The slowed adsorption kinetics caused by the constricted pore shape of adsorbents is a significant obstacle in heavy metal ion adsorption. In order to develop effective and environmentally friendly adsorbents for the removal of heavy metal ions, particularly from phosphoric acid medium, novel resources are needed. Biochar, generated from waste biomass as a low-cost and non-toxic material, is currently attracting a great deal of interest as a potential solution. In this study, banana pseudostem was selected and pyrolyzed at 650 degrees C to evaluate its effect on cadmium adsorption. The resulting biochar was characterized in terms of its structural, physical, morphological, and thermal properties to determine its physicochemical features. The biochar's adsorption efficiency towards Cd removal from industrial phosphoric acid was also evaluated through a series of batch experiments by varying different parameters, including contact time (30-60-180 min), temperature (298.15-308.15-318.15 K), and adsorbent amount (0.05-0.1-0.15-0.2 g). Results from ICP measurements showed that the removal rate of Cd decreased when both time and biochar dosage increased, while temperature had little effect on the extraction process. The biochar was most effective with a removal rate of 12.5 mg/g at 308.15 K by adding 50 mg of biochar for 30 min. These findings suggest that biochar derived from banana pseudostem is a promising biosorbent for Cd removal from industrial phosphoric acid.