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Pollution of waste and natural waters by antibiotics is a major health issue that induces the development of resistant pathogens. Pollutant may be removed by photocatalysis, yet classical photocatalysis is limited by the short carrier lifetime. Here, we review multicomponent photocatalysts for the synergic degradation of antibiotics. Components include metallic nanoparticles, semiconductors and adsorbents. The synergy of these components provide photocatalysts with advantages such as extended visible-light range with bandgap energy lower than 2.8 eV, improved charge transfer properties, enhanced adsorption capacity and more active reaction sites. The removal of the antibiotics, based on the decrease of the initial concentration, reaches 80–100%, but mineralization is rarely measured in reports. Proposed mechanisms for the photocatalytic degradation of antibiotics over single and multicomponent photocatalysts are discussed. [ABSTRACT FROM AUTHOR]

In this study, a novel mixed‐matrix membrane (MMM) based on covalent incorporation of poly(styrene‐alt‐maleic anhydride) (PSMA) with a metal‐organic framework (MOF) UiO‐66‐NH2 was prepared and utilized for dye removal from aqueous solution. The fabrication of PSMA and UiO‐66‐NH2 was carried out by the amidation reaction between the maleic anhydride ring and amino functional group affording crosslinked MOF/PSMA membrane. The separate UiO‐66‐NH2 and PSMA solutions were mixed before cast films were produced. The MMM was prepared with final UiO‐66‐NH2 wt % content from 0 to 30 % in each membrane. The formation of MMM was confirmed with FT‐IR, PXRD, TGA, SEM, and XPS analysis. The MMM having high adsorption capacity was used for the separation of methylene blue (MB) and methyl orange (MO) as organic dye pollutants commonly found in wastewater. The MMM could be recycled and still maintained 75 and 52 % retention of MB and MO on the third reuse cycle, respectively. The results suggest that the MOF incorporated PSMA was an outstanding membrane for the development of filtration techniques for decontamination of water resources. [ABSTRACT FROM AUTHOR]

The occurrence and fate of antibiotic compounds in water can adversely affect human and animal health; hence, the removal of such substrates from soil and water is indispensable. Herein, we described the synthesis method of mesoporous carbon (MPC) via the pyrolysis route from a coordination polymer Fe-based MIL-53 (or MIL-53, shortly). The MPC structure was analyzed by several physical techniques such as SEM, TEM, BET, FT–IR, VSM, and XRD. The response surface methodology (RSM) was applied to find out the effects of initial concentration, MPC dosage, and pH on the removal efficiency of trimethoprim (TMP) and sulfamethoxazole (SMX) antibiotics in water. Under the optimized conditions, the removal efficiencies of TMP and SMX were found to be 87% and 99%, respectively. Moreover, the adsorption kinetic and isotherm studies showed that chemisorption and the monolayer adsorption controlled the adsorption process. The leaching test and recyclability studies indicated that the MPC structure was stable and can be reused for at least four times without any considerable change in the removal efficiency. Plausible adsorption mechanisms were also addressed in this study. Because of high maximum adsorption capacity (85.5 mg/g and 131.6 mg/g for TMP and SMX, respectively) and efficient reusability, MPC is recommended to be a potential adsorbent for TMP and SMX from water media. [ABSTRACT FROM AUTHOR]

The purification of antibiotic compounds-contaminated wastewaters and effluents exhibits the importance of selecting the treatment technologies feasibly. Adsorptive approaches are of tremendous interests in the environmental field mainly due to their outstanding adaptability, large-scaled possibility and ecofriendly sustainability. Herein, we reported the utilization of zeolitic-imidazolate framework (ZIF-8)-derived nitrogen (N)-self-doped mesoporous carbons (ZPC) as a competitive adsorbent for the removal of tetracycline and ciprofloxacin in aqueous solutions. First, ZIF-8 was produced by microwave-assisted synthesis method (450 W, 140 °C, 15 min). N-containing carbons (ZPC x , x = 600, 800, 1000) could be effortlessly reached out through ZIF-8 thermolysis strategy, which the self-sacrificial precursor/template was pyrolyzed at the respective temperatures (600, 800, and 1000 °C). The existence of residual nitrogen in porous carbon structure was observed. Our findings demonstrate that ZPC800 attained a reasonable surface area (268 m2/g) and the superior experimental adsorption capacities (Q exp. = 270.67–317.50 mg/g). The optimal solution pH range was found from 6 for tetracycline to 8 for ciprofloxacin. The experiment was systematically investigated, which the ANOVA analysis were adopted with the confidence level at p < 0.05. ga1 • Porous carbons (ZPCs) were formed by zeolitic-imidazolate framework-8 pyrolysis. • N-self-doped carbon surface contained functional groups favorable for adsorption. • ZPC800 attained reasonable S BET (268 m2/g), and ultrahigh Q m (772.69–905.14 mg/g). • Effect of pyrolysis temperature, pH, dose, concentration, and time was investigated. [ABSTRACT FROM AUTHOR]

• MIL-53 (Fe)-derived carbon was firstly applied for purification of phenolic compounds. • Up to 83% of phenol and 97% of 4-nitrophenol were removed under optimized conditions. • Uptake mechanism includes H-bonding, π–π interaction, electrostatic attraction. • Q m for phenol and 4-nitrophenol on MPC was higher than that on MIL-53 (Fe) and others. The presence of phenolic compounds in aquatic environment, derived from industrial, domestic or agricultural processes adversely affects the human and animals. This study in aimed at the new and effectiveness of an adsorbent, magnetic porous carbon (MPC), for the removal of phenolic compounds including phenol and 4-nitrophenol from aquatic environment. MPC was synthesized from the metal-organic framework MIL-53 (Fe) via the direct pyrolysis at 600 °C. The MPC structure was characterized by several physical techniques and used for the adsorption experiments. To find the best conditions for the removal of phenol and 4-nitrophenol, we empirically investigated the effects of three variables (initial concentration, dosage and pH) on the removal efficiency using the response surface methodology (RSM). Under the RSM-based optimized conditions, up to 83% phenol was removed at the concentration of 16 mg/L, dosage of 0.7, and pH of 6.6, while the figure for 4-nitrophenol was 97%, at concentration of 26.0 mg/L, dosage of 0.75 g/L, and pH of 5.6. In addition, the nonlinear adsorption kinetics and isotherms were employed to interpret the mechanism and calculate the constants of adsorption rate. The uptake results suggested that the adsorption process was controlled by the chemisorption and the monolayer adsorption. The MPC exhibited the remarkable maximum adsorption capacities, which is 4 times (for phenol) and 5 times (for 4-nitrophenol) higher than those exhibited by origin MIL-53 (Fe). Plausible adsorption mechanisms were explained through dipole-dipole H-bonding, π–π interaction and electrostatic attraction. Because of high capacity, effortless performance and good reusability, the MIL-53 (Fe) derived porous carbon can be a promising material for phenolic species remediation in water. [ABSTRACT FROM AUTHOR]

• Effect of thermolysis temperature on characteristics and absorbability towards anti-inflammatory drugs was conducted. • Kinetic, isotherm, and recyclability experiments were systematically studied. • Adsorption mechanisms including H-bond, π–π interaction, metal–oxygen bridging, and electrostatic attraction were rigorously proposed. • Outstanding adsorption capacity (∼144 mg/g), and excellent reusability were monitored with Fe-MIL-88B-derived mesoporous carbon. Discharge of nonsteroidal anti-inflammatory drugs (NSAIDs) from wastewater has been increasingly alarmed, led to the advent of the treatment techniques. Among these methods, adsorption is regarded as a tunable and green approach with the utilization of mesoporous carbon (MC) as an efficient and recyclable adsorbent. Herein, we described the strategy for the synthesis of novel MC from Fe-MIL-88B as a self-sacrificial template. Three thermolysis temperatures (550, 750, and 950 °C) were investigated to compare the structural characteristics and absorbability towards selected NSAIDs compounds including diclofenac sodium (DCF), aspirin (APR), and ibuprofen (IBU). Effect of contact time (0–480 min), concentration (10–40 mg/L), pH (2–10), and MC dosage (0.1–0.5 g/L) was systematically studied. Kinetic and isotherm models were also used to find out the adsorption mechanism and behavior of NSAIDs pharmaceutical over MC materials. Proposed mechanism and recyclability test were rigorously studied to gain more insight into how the NSAIDs molecules adsorb on the MC materials and their potential towards drug treatment. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • In the first time, the mesoporous carbon (MPC) from MIL-53 (Fe) was applied for the treatment of ciprofloxacin antibiotic. • Characterization, optimization, kinetic, isotherm adsorption, stability, and recyclability experiments were studied. • RSM was used as a powerfully mathematical tool to find out the optimal conditions for the removal of ciprofloxacin. • Compared with several studies, the MPC herein exhibited better adsorption capacity, stability, and reusability. Abstract Herein, we have developed a facile method for the synthesis of novel mesoporous carbon-embedded zero-valent Fe sites from the metal-organic framework MIL-53 (Fe) and its utilization for ciprofloxacin antibiotic remediation. To form the porous carbon, the pyrolysis of MIL-53 (Fe) was carried out at 800 °C under nitrogen atmosphere. The characterization results revealed that the MIL-53 (Fe)-based carbon obtained a hierarchically mesoporous structure, high surface area, large pore along with important functional groups. The response surface methodology was also used to find out the optimal conditions for the ciprofloxacin removal. Moreover, the kinetic and isotherm studies were investigated to elucidate the adsorption behavior and mechanism controlled the process. With a high maximum adsorption capacity (90.9 mg/g), good reusability (up to 5 cycles), and chemical stability via leaching test study, the mesoporous carbon derived from MIL-53 (Fe) is proposed to be an effective adsorbent for antibiotic treatment in water. [ABSTRACT FROM AUTHOR]

Chloramphenicol (CAP) is commonly employed in veterinary clinics, but illegal and uncontrollable consumption can result in its potential contamination in environmental soil, and aquatic matrix, and thereby, regenerating microbial resistance, and antibiotic-resistant genes. Adsorption by efficient, and recyclable adsorbents such as mesoporous carbons (MPCs) is commonly regarded as a "green and sustainable" approach. Herein, the MPCs were facilely synthesized via the pyrolysis of the metal–organic framework Fe3O(BDC)3 with calcination temperatures (x °C) between 600 and 900 °C under nitrogen atmosphere. The characterization results pointed out mesoporous carbon matrix (MPC700) coating zero-valent iron particles with high surface area (~225 m2/g). Also, significant investigations including fabrication condition, CAP concentration, effect of pH, dosage, and ionic strength on the absorptive removal of CAP were systematically studied. The optimal conditions consisted of pH = 6, concentration 10 mg/L and dose 0.5 g/L for the highest chloramphenicol removal efficiency at nearly 100% after 4 h. Furthermore, the nonlinear kinetic and isotherm adsorption studies revealed the monolayer adsorption behavior of CAP onto MPC700 and Fe3O(BDC)3 materials via chemisorption, while the thermodynamic studies implied that the adsorption of CAP was a spontaneous process. Finally, adsorption mechanism including H-bonding, electrostatic attraction, π–π interaction, and metal–bridging interaction was proposed to elucidate how chloramphenicol molecules were adsorbed on the surface of materials. With excellent maximum adsorption capacity (96.3 mg/g), high stability, and good recyclability (4 cycles), the MPC700 nanocomposite could be utilized as a promising alternative for decontamination of chloramphenicol antibiotic from wastewater. [ABSTRACT FROM AUTHOR]

Aquatic contamination of diclofenac (DCF), an emergent non-steroidal anti-inflammatory drug (NSAIDs), can result in adverse effects to many ecosystems through biomagnification. Hence, introducing effective remediation techniques to sequester the pharmaceutical wastes is highly fundamental to prevent their accumulation in the environment. Generally, adsorption has been presented as a green and efficient approach. Herein, we report the characterization and application of the novel magnetic nanocomposite (GO@CoFe 2 O 4) derived from cobalt-based ferrite (CoFe 2 O 4) and graphene oxide (GO) for DCF adsorption. For the optimization procedure, the response surface methodology (RSM) was adopted to investigate the impacts of DCF concentration (1.6–18.4 mg/L), DCF dosage (0.08–0.92 g/L), and solution pH (2.6–9.4) to find the optimum conditions for DCF removal, at 10.5 mg/L, 0.74 g/L, and pH 4, respectively. For the adsorption experiments, the kinetic, isotherm, thermodynamic, and intraparticle diffusion models were systematically studied. Moreover, we have elucidated the role of functional groups on the surface of GO@CoFe 2 O 4 in enhancing the adsorption of DCF drug. With good removal efficiency (up to 86.1%), high maximum adsorption capacity (32.4 mg/g), GO@CoFe 2 O 4 can be a potential candidate to eliminate DCF drug from water. Image 1 [ABSTRACT FROM AUTHOR]

The present study focused on the synthesis of novel NH 2 -PC700 adsorbent through the pyrolysis of NH 2 -MIL-88B (Fe) material under different pyrolysis temperatures (500, 700, and 900 °C) and investigated its application for ciprofloxacin adsorption. The obtained adsorbents were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and nitrogen adsorption/desorption isotherm measurements. The parameters of the adsorption experiments that affect the removal efficiency, including solution pH (3–10), contact time (0–240 min), and initial concentration (10–40 mg/L), were also studied in detail. For the adsorption kinetic and isotherm studies, nonlinear models combined with error functions such as adjusted coefficient of determination (R adj 2), mean relative error (MRE), and squares of the errors (SSE) were used to evaluate the compatibility between kinetic models (pseudo-first-order, pseudo-second-order, Elovich, and Bangham) and isotherm (Langmuir, Freundlich, Temkin, and Dubinin–Radushkevitch) adsorption equations. Besides, the role of amino functionalization for the ciprofloxacin (CFX) adsorption of NH 2 -PC700 adsorbent was also explained. Through the Langmuir model, the maximum CFX adsorption capacity of NH 2 -PC700 was calculated to be 102.5 mg/g, considerably higher than that of NH 2 -MIL-88B (Fe). This outcome suggested that NH 2 -PC700 could be a promising adsorbent for the CFX remediation. • The novel NH 2 -PC700 was synthesized from amino-functionalized metal-organic frameworks. • Nonlinear kinetic and isotherm models were fitted well. • Adsorption behavior obeyed pseudo-second-order and Freundlich models. • The maximum ciprofloxacin adsorption capacity was calculated to be 102.5 mg/g. Image 1 [ABSTRACT FROM AUTHOR]

The prevalent presence of antibiotic compounds (e.g., chloramphenicol [CAP]) in wastewater and effluents without pretreatment can bring adverse impacts on human and animals; therefore, the remediation of these substrates is emergently essential. To synthesize the novel mesoporous carbon for chloramphenicol remediation, we pyrolyzed a species of copper-based metal-organic framework, namely Cu 3 (BTC) 2 (BTC = 1,3,5-benzenetricarboxylic acid), at 700 °C, characterized by several physical analytical techniques, such as X-ray powder diffraction, scanning/transmission electron microscopy, and N 2 adsorption/desorption isotherm measurement. The procedure to optimize the optimum conditions for the removal of CAP was conducted based on investigating three factors including concentration (1.6–18.4 mg/L), adsorbent dosage (0.08–0.92 g/L), and pH (2.6–9.4). As a consequence, up to 87.6% of chloramphenicol could be removed from water under these conditions. Moreover, the effects of contact time (0–120 min) and concentration (10–40 mg/L), as well as other adsorption kinetic and isotherm models, were vigorously studied. With a relatively high surface area (78.8 m2/g), many functional groups on the surface (2.44 mmoL/g for acidic and base groups), and high maximum adsorption capacity (37.2 mg/g), the mesoporous carbon from Cu 3 (BTC) 2 can be used as an efficient adsorbent for CAP removal from wastewater. • The novel CMC700 was produced from the pyrolysis of Cu 3 (BTC) 2 metal-organic framework. • Response surface methodology was used to optimize chloramphenicol adsorption. • Kinetic and isotherm models for chloramphenicol adsorption over CMC700 were studied. • The maximum adsorption capacity was 37.2 mg/g. [ABSTRACT FROM AUTHOR]

In this report, the adsorption of Cr(VI) onto MnO 2 /CS nanocomposite material from aqueous solution is investigated. All the factors, which affect the adsorption, such as pH, adsorption time, Cr(VI) initial concentration and adsorbent dosage, are also examined. The results obtained show that the Cr(VI) uptake is strongly affected by pH and ion strength. Analysis within the nonlinear isotherm models indicates that the Sips isotherm combining with the Langmuir and Freundlich models offer the best fit to the experimental data due to the obtained highest R2 and smallest RMSE and χ2 values. The calculated Langmuir monolayer adsorption capacity is 61.56 mg g−1 at pH of 2.0 and adsorption time of 120 min. Moreover, the mechanism studies by combining theoretical models with analytical spectroscopies reveal that the electrostatic attraction plays the important role to the uptake of Cr(VI) onto MnO 2 /CS nanocomposite. Therefore, the present nanocomposite material can be applied to remove total Cr from wastewater produced by the galvanized manufacturing factory with a relatively high efficiency. Image 1 • MnO 2 /CS nanocomposite was used as an adsorbent to remove Cr(VI) from aqueous solution. • The Langmuir monolayer adsorption capacity is 61.56 mg g−1. • The primary mechanism of the uptake of Cr(VI) onto MnO 2 /CS was proposed. • MnO 2 /CS was applied to remove total Cr in effluent with the high removal of 94.21%. [ABSTRACT FROM AUTHOR]