Fabrication of agro-waste lotus leaf-derived adsorbent for effective removal of organic pollutants from water

Full utilization of agricultural waste (agro-waste)-derived adsorbents for water purification is favorably sustainable. Herein, adsorbents obtained from the local lotus leaves are employed to remove the organic pollutants from water. The local lotus-leaf-derived adsorbent followed by 2 g of ZnCl2 activation at 1173 K (LAC-2-1173) exhibits a maximum adsorption capacity of 91.7 mg center dot g(-1) for norfloxacin at 298 K due to its larger specific surface area and hydrophobicity. Meanwhile, LAC-2-1173 possesses a superior adsorption performance of methylene blue and methyl orange with the maximum adsorption capacity of 176.7 mg center dot g(-1) and 246.5 mg center dot g(-1), respectively. The pollutants' adsorption over LAC-2-1173 is exothermic and spontaneous, and the adsorption kinetic behavior and adsorption isotherms are well in line with the pseudo-second-order equation and Langmuir model, respectively. This work provides some insight into the fabrication and utilization of local agro-wastes-derived materials for environmental remediation.