Removal Performance and Mechanism of Emerging Pollutant Chloroquine Phosphate from Water by Iron and Magnesium Co-Modified Rape Straw Biochar

Abstract

Chloroquine phosphate (CQP) is effective in treating coronavirus disease 2019 (COVID-19); thus, its usage is rapidly increasing, which may pose a potential hazard to the environment and living organisms. However, there are limited findings on the removal of CQP in water. Herein, iron and magnesium co-modified rape straw biochar (Fe/Mg-RSB) was prepared to remove CQP from the aqueous solution. The results showed that Fe and Mg co-modification enhanced the adsorption efficiency of rape straw biochar (RSB) for CQP with the maximum adsorption capacity of 42.93 mg/g (at 308 K), which was about two times higher than that of RSB. The adsorption kinetics and isotherms analysis, as well as the physicochemical characterization analysis, demonstrated that the adsorption of CQP onto Fe/Mg-RSB was caused by the synergistic effect of pore filling, π-π interaction, hydrogen bonding, surface complexation, and electrostatic interaction. In addition, although solution pH and ionic strength affected the adsorption performance of CQP, Fe/Mg-RSB still had a high adsorption capability for CQP. Column adsorption experiments revealed that the Yoon–Nelson model better described the dynamic adsorption behavior of Fe/Mg-RSB. Furthermore, Fe/Mg-RSB had the potential for repeated use. Therefore, Fe and Mg co-modified biochar could be used for the remediation of CQP from contaminated water.

Efficient Adsorption of Tebuconazole in Aqueous Solution by Calcium Modified Water Hyacinth-Based Biochar: Adsorption Kinetics, Mechanism, and Feasibility

“…In addition, the pore volume and average pore size of WHCBC were higher than those of WHBC. This may be due to the collapse of the pore wall caused by the calcium modification of the biochar [37], which increased the pore size and thus significantly increased the pore volume of the mesopores after modification (Table 1). It is well known that the larger the specific surface area and pore volume of the biochar, the higher the physical adsorption capacity of the biochar.…”

Efficient Recovery of Phosphate from Water Media by Iron-Magnesium Functionalized Lignite: Adsorption Evaluation, Mechanism Revelation and Potential Application Exploration

“…The calcium/magnesium-modified lignite prepared by Samaraweera et al also obtained similar results for the removal of phosphate from wastewater [ 10 ]. Sun et al prepared an Fe–Mg co-modified rape straw biochar (Fe/MG-RSB), whose maximum adsorption capacity for chloroquine phosphate was 42.93 Mg/g (308 K), which was about two times higher than that of unprocessed rape straw biochar [ 17 ]. Tang et al prepared an Fe–Mg layered dioxide-modified bagasse waste adsorbent (BM-LDO-BC), whose maximum theoretical adsorption capacity of ciprofloxacin in water reached 213.1 mg/g [ 18 ].…”