High efficiency removal of ibuprofen in water using activated carbon derived from Radix Angelica Dahurica residue

Abstract

Abstract The exploitation and utilization of Traditional Chinese medicine has produced large numbers of waste residue including Radix Angelica Dahurica residue (RAR) and raised environmental concerns. Meantime, the non-steroidal anti-inflammatory drug of ibuprofen (IBP) is an emerging contaminant in the aquatic environment. RAR was utilized to prepare activated carbons (AC) to remove IBP from water firstly. Two kinds AC modified without (RAR-AC) and withphosphoric acid (M-RAR-AC) were characterized by FT-IR, TG, BET and SEM. The phosphoric acid activation contributes to the high BET surface area, large total pore volume, and efficient IBP removal of M-RAR-AC. M-RAR-AC shows considerable advantages in contaminant cleanup and time efficiency than RAR-AC and commercial AC. The enhancement of IBP removal with M-RAR-AC was investigated further by varying initial pollutant concentration, absorbent dosage, temperature, pH and rotating speed. Especially, temperature nearly has no effect on IBP removal by M-RAR-AC. IBP removal of 93.3 ± 0.1% and 64.2 ± 2.8% was achieved for first and fifth cycle, respectively. Kinetic studies suggested that the pseudo-second-order model can fit well and chemisorption plays the dominant role on IBP removal. These findings provide new insights into the utilization of RAR for preparing AC and highlight the potential applications for treating industrial wastewater.