Salt sealing induced in situ N-doped porous carbon derived from wheat bran for the removal of doxycycline from aqueous solution

• Published in: Environmental science and pollution research international 2022-07, Vol.29 (32), p.49346-49360
• Main Authors: Liang, Linlin, Niu, Xinyong, Han, Xiuli, Chang, Chun, Chen, Junying
• Format: Article
• Language: English
• Subjects: Adsorbents; Adsorption; Antibiotics; Aquatic Pollution; Aqueous solutions; Atmospheric Protection/Air Quality Control/Air Pollution; Carbon; Design optimization; Dietary Fiber; Dosage; Doxycycline; Earth and Environmental Science; Ecotoxicology; electrostatic interactions; Electrostatic properties; Endothermic reactions; endothermy; Environment; Environmental Chemistry; Environmental Health; Environmental science; experimental design; Hydrogen bonding; Hydrogen-Ion Concentration; Kinetics; Lewis acid; pH effects; Porosity; Process parameters; Research Article; Response surface methodology; Sealing; sorption isotherms; Thermodynamics; Waste Water Technology; Wastewater; Water; Water Management; Water Pollutants, Chemical - analysis; Water Pollution Control; Wheat; Wheat bran; X ray photoelectron spectroscopy
• ISSN: 0944-1344; 1614-7499
• DOI: 10.1007/s11356-022-19186-y

In situ N-doped porous carbon (NPC) derived from wheat bran via a convenient salt sealing and air-assisted strategy was prepared for the removal of doxycycline (DOX) from aqueous solution. The NPC was precisely characterized by SEM, FTIR, XPS and BET analysis. Additionally, the experimental variables including contact time, adsorbent dosage of NPC and pH were optimized by using Box–Behnken design (BBD) under response surface methodology (RSM). The predicted adsorption capacity of DOX was found to be 291.14 mg g −1 under optimalizing experimental conditions of 196 min contact time, 0.2 g L −1 adsorbent dosage and pH 5.78. The adsorption experimental data fitted Langmuir, Koble-Corrigan and Redlich-Peterson models well, and the pseudo-second-order model perfectly described the DOX adsorption process onto NPC. Thermodynamic parameters of DOX adsorbed onto NPC indicated that the adsorption process was spontaneous and endothermic. Moreover, the adsorption of DOX on NPC was mostly controlled by electrostatic interaction, π-π electron–donator–acceptor (EDA) interaction, hydrogen-bonding and Lewis acid–base effect. Besides, the N element of NPC also played a role in capturing DOX. The maximum monolayer adsorption capacity of DOX was turn out to be 333.23 mg g −1 at 298 K, which suggested that the NPC could be a prospectively adsorbent for the removal of DOX from wastewater.