<![CDATA[The study aims to utilize waste from manga fruit, especially seed shells, as raw material for chromium metal adsorbents in water. Utilizing this waste is one way to support the principle of zero waste for agricultural and plantation products. The biochar preparation process is carried out by pyrolysis, namely, burning in the absence of oxygen. To determine the adsorption capacity of biochar from mango seed shells for chromium ions, analysis was carried out by varying the biochar weight and chromium concentration. The results showed that at carbonisation temperatures of 350 oC, 400 oC, and 450 oC, the water content was 7.5 %, 6.4 %, and 6.2 %, respectively, while the ash content was 6.3 %, 5.9 %, and 5 %, respectively. 6 % respectively. The optimum biochar weight was determined using 20 mg, 40 mg, 60 mg, 80 mg, and 100 mg of biochar. In contrast, the optimum concentration was determined using biochar concentrations of 20 ppm, 40 ppm, 60 ppm, 80 ppm, and 100 ppm. The research results showed that the optimal weight of mango seed shell biochar at a biochar temperature of 450 °C was 100 mg, with a chromium absorption percentage of 92.96%. Meanwhile, the optimum concentration is 20 ppm across all biochars, with chromium absorption of 92.05% for the 450 °C biochar. Manga seed shells have economic value and environmental remediation applications, as they can be converted into adsorbents for chromium metal.]]>
