Salt template synthesis of hierarchical porous carbon adsorbents for Congo red removal

Water-soluble salt was used as a template to fabricate a series of hierarchical porous carbon materials (HPCs). HPCs prepared with 4 g salt template and thermally treated at 700 ? (HPCs-4-700) presents a 3D honeycomb-like microstructure with a large specific surface area of 705.51 m(2) g(-1), and large pore volume of 1.73 cm(3) g(-1). HPCs-4-700 adsorbent shows a fast adsorption rate and high capacity toward Congo red (CR) dye. It can be found that the adsorption process follows the pseudo-second-order kinetics and Langmuir isotherm models with a maximum capacity of 869.73 mg g(-1). Due to high performance and simple preparation process, HPCs-4-700 might be a promising candidate for the removal of CR in wastewater.