Sonophotocatalytic degradation of bisphenol A and its intermediates with graphitic carbon nitride

Synthesis, characterization and photocatalytic activity of alginate based hybrid material for efficient degradation of organic pollutants under UV light and sunlight irradiation

This study reports the development of alginate based hybrid material (Alg/CuO-gC₃N₄) with copper oxide (CuO) and graphitic carbon nitride (gC₃N₄). The Alg/CuO-gC₃N₄ hydrogel bead was prepared by two step process is as follows: formation of CuO-gC₃N₄ by co-precipitation method and incorporation of CuO-gC₃N₄ in the calcium alginate (Alg) by ionotropic gelation method. The structural and morphological features of the Alg/CuO-gC₃N₄ was characterized using different techniques namely Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Thermogravimetric analysis (TGA), UV Diffuse Reflectance spectroscopy (UV-DRS) and Scanning electron microscopy (SEM). The photocatalytic activity of the Alg/CuO-gC₃N₄ was extensively evaluated by degrading methylene blue (MB) under UV-vis and sunlight irradiation. The influence of various parameters like pollutant type, initial dye concentration, catalyst dosage, effect of pH, light intensity and reusability was investigated. The Alg/CuO-gC₃N₄ achieved a maximum degradation efficiency of 86.26 % and 85.15 % for MB at a dye concentration of 1 × 10-5 M under UV-vis and sunlight irradiation respectively, within 60 min using 0.3 wt% of catalyst dosage. The Alg/CuO-gC₃N₄ exhibited excellent stability and reusability over multiple cycles. Additionally, the incorporation of CuO-gC₃N₄ in alginate facilitates in reducing the bandgap (2.54 to 2.28 eV) for efficient charge separation, further enhancing the overall photocatalytic activity.

Alginate/CuO-gC3N4 composite: a novel, reusable, non-toxic photocatalyst for methylene blue degradation

Increasing industrial contamination necessitates development of sustainable water treatment solutions. Photocatalysis is a green technology utilizing light-activated materials (photocatalysts), which can degrade pollutants into harmless by-products. It is an emergent need to develop a photocatalyst that presents a significant advancement for sustainable water treatment and non-toxic to the environment. This study investigates the photocatalytic activity and in vitro cytotoxicity of a novel hybrid material comprising of alginate, copper oxide (CuO) and graphitic carbon nitride (gC3N4) for methylene blue (MB) degradation. The hybrid material was synthesized by a two-step process: (i) doping of CuO on gC3N4 through co-precipitation method formed CuO-gC3N4 (CG) and (ii) incorporation of CG in the calcium alginate (A) by ionotropic gelation method that is named as ACG. The characteristic features of the synthesized A, CG and ACG were studied using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and thermogravimetric analysis (TGA). The optical characteristic of A, CG and ACG was studied using UV-diffuse reflectance spectroscopy (UV-DRS). The morphology and elemental composition of ACG was evaluated by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). To assess the environmental impact of ACG, a two-step approach was employed. First, the photocatalytic activity of ACG under UV-visible light (UV-vis) irradiation for MB degradation was evaluated. ACG exhibited photocatalytic activity by achieving 86.26% of degradation efficiency for MB within 60 min. Second, the in vitro cytotoxicity of ACG, MB and MB degraded products towards tilapia gill cell lines were assessed. By comparing the toxicity of the MB and the secondary products, it is concluded that the overall process leads to a sustainable outcome.

Visible-light-prompted photoelectrochemical sensors fabricated using Er3NbO7/P@g-C3N4/SnS2 nanocomposite for detecting mercury ion in environmental water samples

Photoelectrochemical (PEC) detection technology is key for fighting pollution, leveraging the photoelectric conversion of the photoelectrode material. A specialized photoelectrode was developed to detect Hg2+ ions with exceptional sensitivity, utilizing an anodic PEC sensor composed of Er3NbO7/P@g-C3N4/SnS2 ternary nanocomposite. Rare earth metal niobates (RENs) were chosen due to their underexplored potential, whose performance was enhanced through bandgap engineering and surface modification, facilitated by P@g-C3N4 as an immobilization matrix and SnS2, belonging to the I-IV semiconductors category fostering hybrid heterojunction formation for boasting optical properties and suitable redox potentials. Introducing Hg2+ into the system, a specific amalgamation reaction occurs between reduced Hg and Sn. This reaction obstructs electron transfer to the FTO electrode surface, leading to the recombination of charges. The proposed PEC sensor exhibited remarkable analytical performance for Hg2+ detection, high sensitivity, a detection limit of 0.019 pM, excellent selectivity, and a detectable concentration range of 0.002-0.15 nM. Additionally, it demonstrated good recovery and low relative standard deviation when analyzing Hg2+ in water samples, highlighting the potential application of the heterostructure in detecting heavy metal ions via PEC technology.

Enhancing the efficiency of magnetically driven carbon nitride-based nanocomposites with magnetic nanoflowers for the removal of methylene blue dye at neutral pH

The present study focuses on the elaboration of magnetic nanocomposites by the in situ incorporation of magnetite (Fe3O4) nanoparticles (NPs) with spherical and nanoflower-like morphologies in graphitic carbon nitride (g-C3N4) sheets using two different synthetic routes. Nanomaterials are characterized by TEM, SEM, XRD, FTIR, BET, zetametry, vibrating sample magnetometry, and UV-vis absorption spectroscopy. The decoration of the carbon nitride matrix with the magnetic NPs enhanced optical and textural properties. The influence of the morphology of the magnetic NPs on the adsorptive and photocatalytic properties of the nanocomposites under different pH conditions (4.5, 6.9, and 10.6) was assessed from batch tests to remove methylene blue (MB) from aqueous solutions. In extreme pH conditions, the nanocomposites exhibited lower or equivalent MB removal capacity compared to the pure g-C3N4. However, at neutral medium, the nanocomposite with incorporated Fe3O4 nanoflowers showed a significantly higher removal efficiency (80.7%) due to the combination of a high adsorption capacity and a good photocatalytic activity in this pH region. The proposed nanocomposite is a promising alternative to remove cationic dyes from water by magnetic assistance, since no pH adjustment of the polluted effluent is required, reducing costs and environmental impact in the dyeing industry.

Impact of graphene oxide on visible light photocatalytic performance of graphene oxide/graphitic carbon nitride three-dimensional structure composites

The non-metallic catalyst graphitic carbon nitride (g-C3N4) has attracted a significant amount of attention due to its excellent photocatalytic performance. The photocatalytic performance of g-C3N4 has been further enhanced by the incorporation of graphene oxide (GO) as a composite catalyst. However, the enrichment and recovery of these two-dimensional composites after photocatalysis is still a difficult challenge. In this work, a visible light responsive graphene oxide/graphitic carbon nitride coated sponge three-dimensional composite (PU-GO/g-C3N4) was prepared by electrostatic self-assembly using polyurethane sponge (PU) as a skeleton and g-C3N4 as a photocatalyst. The degradation rate of rhodamine B (RhB) under visible light was used as an index to evaluate the photocatalytic performance of PU-GO/g-C3N4. The results demonstrate that during the photocatalytic degradation of RhB by PU-GO/g-C3N4, g-C3N4 is the main photocatalyst, while the holes and the superoxide radicals generated by electron excitation are the main agents. As a bridge connecting PU and g-C3N4, GO improves the agglomeration phenomenon of g-C3N4 on PU. Meanwhile, GO has excellent carrier mobility and inhibits the recombination of photogenerated electrons and holes. Moreover, the presence of GO enhances the absorption of light and dyes. Overall, the addition of GO effectively enhances the photocatalytic performance of PU-GO/g-C3N4 due to it enhances dye absorption, improves light energy utilization rate, and expedites transfer of photogenerated electrons. After 5 cycles, PU-GO/g-C3N4 still exhibits an RhB degradation rate of 92.06%, demonstrating good stability and recycling performance. This material shows great promise for practical environmental remediation applications.

Synthesis of novel antibacterial and biocompatible polymer nanocomposite based on polysaccharide gum hydrogels

According to recent studies on the benefits of natural polymer-based hydrogels in biomedical applications, gellan gum (GG)/acacia gum (AG) hydrogel was prepared in this study. In order to regulate the mechanical behavior of the hydrogel, graphite carbon nitride (g-C3N4) was included in the hydrogel matrix. In addition, metal oxide nanoparticles ZnCuFe2O4 were added to the composite for antibacterial activity. The prepared GG-AG hydrogel/g-C3N4/ZnCuFe2O4 nanobiocomposite was characterized by using FE-SEM, FTIR, EDX, XRD and TGA. The nanobiocomposite exhibited spherical morphology, which was related to the incorporation of the metal oxide nanoparticles. GG-AG hydrogel/g-C3N4/ZnCuFe2O4 nanobiocomposite showed 95.11%, 92.73% and 88.97% biocompatibility toward HEK293T cell lines within 24 h, 48 h and 72 h incubation, respectively, which indicates that this nanobiocomposite is completely biocompatible with healthy cells. Also, the nanobiocomposite was able to inhibit Pseudomonas aeruginosa biofilm growth on its surface up to 87%. Rheological studies showed that the nanobiocomposite has a viscoelastic structure and has a water uptake ratio of 93.2%. In comparison with other similar studies, this nanobiocomposite has exhibited superior antibacterial activity complete biocompatibility and proper mechanical properties, high swelling and water absorption capability. These results indicate that GG-AG hydrogel/g-C3N4/ZnCuFe2O4 nanocomposite can be considered as a potential candidate for biomedical applications such as tissue engineering and wound healing.

Iron/vanadium co-doped tungsten oxide nanostructures anchored on graphitic carbon nitride sheets (FeV-WO3@g-C3N4) as a cost-effective novel electrode material for advanced supercapacitor applications

In this work, we studied the effect of iron (Fe) and vanadium (V) co-doping (Fe/V), and graphitic carbon nitride (g-C3N4) on the performance of tungsten oxide (WO3) based electrodes for supercapacitor applications. The lone pair of electrons on nitrogen can improve the surface polarity of the g-C3N4 electrode material, which may results in multiple binding sites on the surface of electrode for interaction with electrolyte ions. As electrolyte ions interact with g-C3N4, they quickly become entangled with FeV-WO3 nanostructures, and the contact between the electrolyte and the working electrode is strengthened. Herein, FeV-WO3@g-C3N4 is fabricated by a wet chemical approach along with pure WO3 and FeV-WO3. All of the prepared samples i.e., WO3, FeV-WO3, and FeV-WO3@g-C3N4 were characterized by XRD, FTIR, EDS, FESEM, XPS, Raman, and BET techniques. Electrochemical performance is evaluated by cyclic voltammetry (CV), galvanic charge/discharge (GCD), and electrochemical impedance spectroscopy (EIS). It is concluded from electrochemical studies that FeV-WO3@g-C3N4 exhibits the highest electrochemical performance with specific capacitance of 1033.68 F g-1 at scan rate 5 mV s-1 in the potential window range from -0.8 to 0.25 V, that is greater than that for WO3 (422.76 F g-1) and FeV-WO3 (669.76 F g-1). FeV-WO3@g-C3N4 has the highest discharge time (867 s) that shows it has greater storage capacity, and its coulombic efficiency is 96.7%, which is greater than that for WO3 (80.1%) and FeV-WO3 (92.1%), respectively. Furthermore, excellent stability up to 2000 cycles is observed in FeV-WO3@g-C3N4. It is revealed from EIS measurements that equivalent series resistance and charge transfer values calculated for FeV-WO3@g-C3N4 are 1.82 Ω and 0.65 Ω, respectively.

Mg/Li@GCN as highly active visible light responding 2D photocatalyst for wastewater remediation application

In this study, a highly visible light responding 2D photocatalytic material has been prepared and analysed for its potential for photodegradation of organic pollutants. The pristine GCN has been co-doped with Mg/Li using the facile synthesis route. The prepared photocatalytic materials were then analysed using characterisation techniques like X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, diffuse reflectance spectra (DRS) and photoluminescence spectroscopy (PL) analysis. The prepared samples were analysed for photocatalytic degradation analysis towards methylene blue dye. The apparent rate constant value increased up to 5.4 times in the case of the GCNML (0.5,2) sample in comparison to GCNP. In addition, the GCNML (0.5,2) sample was also analysed for degradation of crystal violet (CV) (97% in 80 min), rose bengal (RB) (84% in 120 min) and methyl orange (MO) (45% in 120 min) dyes. The result obtained from the study confirmed that GCNML (0.5,2) can act as a potential photocatalyst for wastewater remediation application.

O and S co-doping induced N-vacancy in graphitic carbon nitride towards photocatalytic peroxymonosulfate activation for sulfamethoxazole degradation

Doping-induced vacancy engineering of graphitic carbon nitride (GCN) is beneficial for bandgap modulation, efficient electronic excitation, and facilitated charge carrier migration. In this study, synthesis of oxygen and sulphur co-doped induced N vacancies (OSGCN) by the hydrothermal method was performed to activate peroxymonosulfate (PMS) for sulfamethoxazole (SMX) antibiotic degradation and H₂ production. The results from experimental and DFT simulation studies validate the synergistic effects of co-dopants and N-vacancies, i.e., bandgap lowering, electron-hole pairs separation, and high solar energy utilization. The substitution of sp² N atom by O and S co-dopants causes strong delocalization of HOMO-LUMO distribution, enhancing carrier mobility, increasing reactive sites, and facilitating charge-carrier separation. Remarkably, OSGCN/PMS photocatalytic system achieved 99.4% SMX degradation efficiency and a high H₂ generation rate of 548.23 μ mol g^-1 h^-1 within 60 min and 36 h, respectively under visible light irradiations. The SMX degradation kinetics was pseudo-first-order with retained recycling efficiency up to 4 catalytic cycles. The results of EPR and chemical scavenging experiments revealed the redox action of reactive oxidative species, wherein ¹O₂ was the dominant reactive species in SMX degradation. The identification of formed intermediates and the SMX stepwise degradation pathway was investigated via LC-MS analysis and DFT studies, respectively. The results from this work anticipated deepening the understanding of PMS activation by substitutional co-doping favoring N-vacancy formation in GCN lattice for improved photocatalytic activity.

Fast light-switchable polymeric carbon nitride membranes for tunable gas separation

Switchable gas separation membranes are intriguing systems for regulating the transport properties of gases. However, existing stimuli-responsive gas separation membranes suffer from either very slow response times or require high energy input for switching to occur. Accordingly, herein, we introduced light-switchable polymeric carbon nitride (pCN) gas separation membranes with fast response times prepared from melamine precursor through in-situ formation and deposition of pCN onto a porous support using chemical vapor deposition. Our systematic analysis revealed that the gas transport behavior upon light irradiation is fully governed by the polarizability of the permeating gas and its interaction with the charged pCN surface, and can be easily tuned either by controlling the power of the light and/or the duration of irradiation. We also demonstrated that gases with higher polarizabilities such as CO2 can be separated from gases with lower polarizability like H2 and He effectively with more than 22% increase in the gas/CO2 selectivity upon light irradiation. The membranes also exhibited fast response times (<1 s) and can be turned “on” and “off” using a single light source at 550 nm.

Fast light-switchable polymeric carbon nitride membranes for tunable gas separation

Switchable gas separation membranes are intriguing systems for regulating the transport properties of gases. However, existing stimuli-responsive gas separation membranes suffer from either very slow response times or require high energy input for switching to occur. Accordingly, herein, we introduced light-switchable polymeric carbon nitride (pCN) gas separation membranes with fast response times prepared from melamine precursor through in-situ formation and deposition of pCN onto a porous support using chemical vapor deposition. Our systematic analysis revealed that the gas transport behavior upon light irradiation is fully governed by the polarizability of the permeating gas and its interaction with the charged pCN surface, and can be easily tuned either by controlling the power of the light and/or the duration of irradiation. We also demonstrated that gases with higher polarizabilities such as CO2 can be separated from gases with lower polarizability like H2 and He effectively with more than 22% increase in the gas/CO2 selectivity upon light irradiation. The membranes also exhibited fast response times (<1 s) and can be turned “on” and “off” using a single light source at 550 nm.

Key Points of Advanced Oxidation Processes (AOPs) for Wastewater, Organic Pollutants and Pharmaceutical Waste Treatment: A Mini Review

Advanced oxidation procedures (AOPs) refer to a variety of technical procedures that produce OH radicals to sufficiently oxidize wastewater, organic pollutant streams, and toxic effluents from industrial, hospital, pharmaceutical and municipal wastes. Through the implementation of such procedures, the (post) treatment of such waste effluents leads to products that are more susceptible to bioremediation, are less toxic and possess less pollutant load. The basic mechanism produces free OH radicals and other reactive species such as superoxide anions, hydrogen peroxide, etc. A basic classification of AOPs is presented in this short review, analyzing the processes of UV/H2O2, Fenton and photo-Fenton, ozone-based (O3) processes, photocatalysis and sonolysis from chemical and equipment points of view to clarify the nature of the reactive species in each AOP and their advantages. Finally, combined AOP implementations are favored through the literature as an efficient solution in addressing the issue of global environmental waste management.

Graphitic carbon nitride and APTES modified advanced electrochemical biosensor for detection of 17β-estradiol in spiked food samples

This work demonstrates a simple and inexpensive electrochemical biosensing pathway for selective and sensitive recognition of 17β-estradiol (E2) in environmental and food samples. The biosensing system is based on graphitic carbon nitride (g-C₃N₄) and a conductive polymer 3-aminopropyltriethoxysilane (APTES). The proposed biosensor shows the ability to detect E2 in attomolar levels within a wide linear logarithm concentration range of 1 × 10⁻⁶ to 1 × 10⁻¹⁸ mol L⁻¹ with a limit of detection (LOD) of 9.9 × 10⁻¹⁹ mol L⁻¹. The selectivity of the developed biosensor was confirmed by conducting the DPV of similarly structured hormones and naturally occurring substances. The proposed biosensor is highly stable and applicable to detect E2 in the presence of spiked food and environmental samples with satisfactory recoveries ranging from 95.1 to 104.8%. So, the designed electrochemical biosensor might be an effective alternative tool for the detection of E2 and other endogenous substances to attain food safety.

This work demonstrates a simple and inexpensive electrochemical biosensing pathway for selective and sensitive recognition of 17β-estradiol (E2) in environmental and food samples.

Reducing the reproductive toxicity activity of Lactiplantibacillus plantarum: a review of mechanisms and prospects

Food pollution can cause a variety of negative effects on human health, especially reproductive toxicity. Common food contaminants include biological contaminants, chemical contaminants, and physical contaminants, among which endocrine disruptors, pesticides, and heavy metals have the greatest reproductive toxicity in chemical contaminants. Humans mainly solve food pollution through three aspects: decreasing the pollution of food raw materials, lowering the pollution in food processing, and reducing the harm to the human body after food pollutants enter the human body. With more and more research on probiotics, not only beneficial effects, but also the ability to reduce the toxicity of food contaminants is found. Thus, microbial treatment has been proved to be a more effective way to deal with food pollution. Recent research shows that several strains of Lactiplantibacillus plantarum can adsorb or degrade some chemical pollutants and relieve inflammation and oxidative stress caused by them. This review summarized the research to explore the possible role of Lactiplantibacillus plantarum in protecting human reproductive ability and maintaining food safety.

Application of advanced materials in sonophotocatalytic processes for the remediation of environmental pollutants

Significant advances in various industrial processes have resulted in the discharge of toxic pollutants into the environment. Consequently, it is essential to develop efficient wastewater treatment processes to reduce water contamination and increase recycling/reuse. Photocatalytic degradation is considered as an efficient method for the degradation of toxic pollutants in industrial wastewater. However, the use of photocatalytic approaches is associated with numerous limitations, such as lengthy procedures and the necessity for large amounts of catalysts. Hence, it has been proposed that photocatalysis could be combined with other techniques, including sonolysis, electrochemical, photothermal, microwave, ultrafiltration, and biological reactor. The integration of photocatalysis with sonolysis could be remarkably beneficial for environmental remediation. The combination of these processes has the advantages of using uniformly dispersed catalysts, regeneration of the catalyst surface, improved mass transfer, enhanced surface area due to smaller catalyst particles, and production of more active radicals for the degradation of organic pollutants. In this review, an overview on employing sonophotocatalysis for the removal of toxic organic contaminants from aqueous environments is provided. Additionally, the limitations of photocatalysis alone and the fundamental sonophotocatalytic mechanistic pathways are discussed. The importance of utilizing advanced two-dimensional (2D) semiconductor materials in sonophotocatalysis and the common synthetic approaches for the preparation of 2D materials are also highlighted. Lastly, the review provides comprehensive insights into different materials based on metal oxides, chalcogenides, graphene, and metal organic frameworks (MOFs), which are involved in sonophotocatalytic processes employed for the remediation of environmental pollutants.

Graphitic carbon nitride: a sustainable photocatalyst for organic pollutant degradation and antibacterial applications

Recently, graphitic carbon nitride (GCN) has been found to be of great interest in various sustainable applications. In this study, a simple preparation method using urea was utilized to synthesize GCN. In order to understand various morphological, structural, and optical aspects of the as-prepared sample, GCN was characterized using X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, Brunauere-Emmette-Teller (BET), scanning electron microscopy (SEM), and diffused reflectance spectra (DRS) analysis. The visible-light-driven photocatalytic activity of prepared GCN was analyzed for various cationic dyes (Crystal violet, rose bengal, rhodamine B, auramine O, methylene blue) and anionic dyes (phenol red, xylenol orange, cresol red, methyl orange). The calculated efficiencies of degradation and values of apparent rate constant for all dye samples suggested that cationic dyes are more actively degraded using GCN than anionic dyes. In addition, GCN was further analyzed for its splendid antibacterial activity against pathogenic bacteria (Klebsiella pneumonia and Escherichia coli). The synthesized photocatalyst holds a bright scope for the efficient remediation of organic pollutants and bacterial disinfection in wastewater. Graphical abstract.

Improvements in Catalyst Synthesis and Photocatalytic Oxidation Processing Based on the Use of Ultrasound

The efficacy of photocatalysis strongly depends on the activity of the catalysts and the operational factors, especially factors associated with mass transfer and the possibility of catalyst deactivation. The use of ultrasound has great potential to enhance catalyst activity, during both the synthesis and actual oxidation processes due to the cavitational effects of turbulence and liquid streaming. This article presents an overview of the application aspects of ultrasound, both in the synthesis of the photocatalyst and applications for wastewater treatment. A review of the literature revealed that the use of ultrasound in the synthesis processes can result in a catalyst with a lower mean size and higher surface area as well as uniform size distribution. The application of ultrasound in the actual photocatalytic oxidation facilitates enhancement of the oxidation capacity, leading to higher degradation rates, sometimes synergistic results and definitely lower treatment times. This article also presents guidelines for the selection of the best operating conditions for the use of ultrasound in photocatalytic systems and includes a discussion on the possible reactor configurations suitable for large-scale operations. Overall, a combination of ultrasound with photocatalytic oxidation or the optimized application of ultrasound in catalyst synthesis can yield significant benefits.

Sono-photo-assisted heterogeneous activation of peroxymonosulfate by Fe/CMK-3 catalyst for the degradation of bisphenol A, optimization with response surface methodology

The present study examined the removal of bisphenol A (BPA) and total organic carbon (TOC) from aqueous solutions by the Fe/CMK-3 as peroxymonosulfate activator used in the sono-photo-catalytic process. The synthesis of Fe/CMK-3 was carried out using the co-precipitation method, and it was characterized by FTIR, XRD, BET, EDX, and TEM. The results showed that the iron nanoparticles were uniformly embedded in the CMK-3 pores. The effect of factors affecting on the removal of BPA and TOC was evaluated by response surface methodology (RSM) with center composite design (CCD). The analysis of variance of the quadratic model showed that the model is significant (p value < .0001 and R²  > 99.4%) and can be used to optimize the removal efficiency of BPA. Optimization results showed that the highest removal efficiency of BPA (100%) and TOC (80.6%) was achieved in optimum conditions of pH 7.8, catalyst dose 0.33 g/L, PMS dose 3.35 mmol/L, BPA concentration 39.3 mg/L, and 78.5 min. In addition, statistical analysis of the data showed that, in the studied range, the initial concentration of BPA was the most influential factor, followed by pH and PMS dose. Highest catalytic stability of Fe/CMK-3 showed the potential applicability of catalyst in the treatment of BPA-containing solutions. The quenching test showed that sulfate radical was the main responsible for the removal of BPA. The decrease in I_OUR value after the 75-min reaction time indicates that this process has a high ability for oxidation of the pollutant and its intermediates. Generally, the observed results suggest that the Fe-CMK-3/UV/US/PMS system can be a promising procedure for the removal of persistent pollutants such as BPA from aqueous media. PRACTITIONER POINTS: Fe/CMK-3 exhibited prominent catalytic activity and high stability for peroxymonosulfate activation. Effective degradation of bisphenol A was achieved in the Fe-CMK-3/UV/US/PMS system. The effect of five factors at five levels and their interactions during the removal of BPA was evaluated by RSM method coupled with central composite design (CCD). The analysis of variance of the quadratic model showed that the model is very significant (p value < .0001) and can be used to optimize the removal efficiency of BPA. The quenching test showed that sulfate radical was the main responsible for the removal of BPA. Reducing I_OUR value after the 75-min reaction time indicates that toxicity of the solution was significantly decreased in this system.