Adsorption Characteristics of Cr6+ and As3+ Using Seaweed Biochar

This study examined the adsorption characteristics of Cr and As in the aqueous solution by Hizikia susiformis biochar which was collected from Jeju Island. The optimal pH for Cr and As adsorption were 2 and pH 6, respectively. Kinetic data showed that the adsorption occurred during the first 100 min, and the most of heavy metals were bound to biochars within 300 min. Moreover, the kinetic data presented that the course of adsorption follows the Pseudo first and second order models. The equilibrium data were well fitted by the Langmuir model and the Cr adsorption capacity (25.91 mg/g) was higher than that of As (16.54 mg/g). From these results, the seaweed biochar was shown to be a efficient adsorbent for Cr and As metals in a contaminated environment.