Evaluation of potassium ferrate activated Fe-N-modified carbons from bamboo shoot shells for arsenic removal

Fe-N-modified activated carbons (ACs) were prepared from bamboo shoot shells (BSS) by potassium ferrate activation for arsenic adsorption. BSS provided abundant nitrogen and carbon sources for ACs, while potassium ferrate significantly improved the pore volume and specific surface area (SSA), but also loaded iron particles. The highest SSA of AC was 1900 m2/g, with the iron content of 4.54–6.52% and nitrogen content of 2.88–3.35%. Based on the arsenic adsorption capacity, the optimized manufacturing process was activation temperature of 800 °C, activation time of 120 min, and activator ratio of 3.5. The optimized AC exhibited excellent arsenic adsorption performance and the maximum adsorption capacity was 9.18 mg/g. The good magnetism of AC was beneficial to recovery and reuse. The adsorption capability retention was still more than 50% after reusing for five times. This work showed that BSS had great potential for commercial development, and also provided a cost-effective production way for arsenic adsorbents.