Adsorption behavior of salicylic acid on biochar as derived from the thermal pyrolysis of barley straws. (10th September 2018) - Ahmed, M.J.
Abstract: Abundant wastes of barley straws were utilized as precursor to prepare biochar adsorbent through thermal pyrolysis. Pore characteristics, morphology, and attraction extent of the prepared adsorbent toward salicylic acid were identified. The obtained biochar had a surface area of 435.52 m 2 /g, a pore volume of 0.241 cm 3 /g, and an average pore width of 22.16 Å. The effects of batch adsorption variables, such as initial salicylic acid concentration (50–250 mg/L), contact time (0–24 h), initial pH (3–11), and temperature (25 °C–45 °C) on the biochar performance were tested. Equilibrium data analysis revealed the best correlation of the Langmuir isotherms, with maximum salicylic acid uptakes of 189.12, 197.43, and 210.56 mg/g at 25 °C, 35 °C, and 45 °C, respectively. The salicylic acid/biochar system exhibited spontaneous, chemisorption, and endothermic natures. Considering its favorable pore characteristics and high attraction performance, barley straw biochar could be a suitable adsorbent to eliminate salicylic acid from wastewaters. Graphical abstract: Image Highlights: High performance biochar was prepared from barely straw biomass. Surface area of 435.52 m 2 /g and pore volume of 0.241 cm 3 /g were obtained. Adsorption behaviors were evaluated for salicylic acid removal. Maximum monolayer capacity of 210.53 mg/g was achieved at 45 °C.