Continuous Wastewater Treatment Research Articles

Schottky junctions integrated with S-scheme heterojunctions in recyclable loaded ZnIn2S4/UiO-66/calcined graphite felt photocatalysts with enhanced carrier separation for photocatalytic degradation

Photocatalytic technology holds significant potential in the purification of antibiotic wastewater. However, efficient carrier separation and convenient recyclability are crucial for the practical application of photocatalysts. Herein, a loaded ZnIn2S4/UiO-66/calcined graphite felt (ZU/C-GF) composite photocatalyst was demonstrated to achieve efficient and stable removal of tetracycline hydrochloride (TCH) from water. Detailed characterization and theoretical calculations suggested that ZnIn2S4 could form a Schottky junction with C-GF and an S-scheme heterojunction with UiO-66. The internal electric field (IEF) at the interface could promote the migration of photoelectrons, while the Schottky barrier could inhibit electron backflow. This synergistic strategy maximized the separation of photogenerated electrons and holes, thereby enhancing the photocatalytic performance. The optimal composite material exhibited the highest removal efficiency (97.0 %) and reaction rate (0.02312 min−1) while maintaining comparable degradation performance under solar irradiation. Additionally, this C-GF-based immobilization scheme allowed for rapid recovery and reuse of the photocatalyst, effectively addressing the challenge of recycling. ZU-10/C-CF demonstrated stable reusability after five consecutive cycles, revealing its significant potential for practical applications. This work presents novel insights for coupling Schottky junctions and S-scheme heterojunctions, and describes a more convenient approach for the continuous and stable treatment of antibiotic wastewater.

Modulating structure of Ce-UiO-66 by introducing fluorinated terephthalic acid for enhanced removal efficiency of antibiotics: Insights into degradation kinetics and pathways

In this work, the 2-fluoroterephthalic acid with asymmetric structure and high electronegative F species was introduced in the assembly of Ce-UiO-66 catalysts to increase the defect density and enlarge pore structure for enhancement in removal efficiency of sulfamethoxazole. Owing to the strong coordination ability from high electronegative F species of 2-fluoroterephthalic acid with Ce-oxo nodes, the designed CUF exhibited improved interfacial properties (accelerated electron transfer rate, available active sites and enhanced interaction with PMS), which was favorable for the exploration and accessibility of active sites with sulfamethoxazole and PMS to decrease the adsorption barrier and accelerate PMS activation. As a result, the CUF catalysts exhibited higher adsorption capacity (173.4 mg/g) than that of CUH (117.8 mg/g), the enhanced degradation efficiency of sulfamethoxazole with a rate constant higher than 2.3 times CUH, good elimination (>95 %) of methylene blue, tetracycline and ibuprofen. In addition, the CUF/PMS system possessed satisfactory stability in wide solution pH, recycling and real water and good potential application in continuous wastewater treatment based on the designed dynamic catalytic reactor. This work provided deep insight into the design of catalysts with high adsorption performance and degradation efficiency based on the structure–activity relationship.

Assembly of Chitosan/Caragana Fibers to Construct an Underwater Superelastic 2D Layer-Supported 3D Architecture for Rapid Congo Red Removal.

Developing environmentally friendly bulk materials capable of easily and thoroughly removing trace amounts of dye pollutants from water to rapidly obtain clean water has always been a goal pursued by researchers. Herein, a green material with a 3D architecture and with strong underwater rebounding and fatigue resistance ability was prepared by means of the assembly of biopolymer chitosan (CS) and natural caraganate fibers (CKFs) under freezing conditions. The CKFs can randomly and uniformly distribute in the lamellar structure formed during the freezing process of CS and CKFs, playing a role similar to that of "steel bars" in concrete, thus providing longitudinal support for the 3D-architecture material. The 2D layers formed by CS and CKFs as the main basic units can provide the material with a higher strength. The 3D-architecture material can bear the compressive force of a weight underwater for multiple cycles, meeting the requirements for water purification. The underwater compression test shows that the 3D-architecture material can quickly rebound to its original shape after removing the stress. This 3D-architecture material can be used to purify dye-containing water. When its dosage is 3 g/L, the material can remove 99.65% of the Congo Red (CR) in a 50 mg/L dye solution. The adsorption performance of the 3D architecture adsorbent for CR removal in actual water samples (i.e., tap water, seawater) is superior than that of commercial activated carbon. Due to its porous block characteristics, this material can be used for the continuous and efficient treatment of wastewater containing trace amounts of CR dye to obtain pure clean water, meaning that it has great potential for the effective purification of dye wastewater.

Three-dimensional gel network structure of agarose interlayer dispersed Pd nanoparticles in copper foam electrode for electrocatalytic degradation of doxycycline hydrochloride

In this study, we successfully prepared palladium/agarose/copper foam (Pd/AG/CF) composite electrodes by utilizing the three-dimensional network structure agarose (AG), a green material derived from biomass, and homogeneously immobilizing palladium (Pd) atoms on a copper foam (CF) substrate through a facile route. The electrode showed excellent performance in the electrocatalytic degradation of doxycycline (DOX), with a high DOX degradation rate of 92.19 % in 60 min. In-depth studies revealed that palladium can form metal-metal interactions with the CF substrates, which enhances the electron transfer on the catalyst surface. In addition, the introduction of agarose effectively prevented the agglomeration of palladium nanoparticles. In addition, the hydroxyl functional groups in the molecular structure of agarose facilitate interactions between water molecules and the electrode interface through the formation of hydrogen bonds, thereby further enhancing the efficiency of the electrocatalytic reaction. In addition to good stability and reusability. Microbial toxicity test results show that the degraded wastewater has minimal impact on the environment. Also, possible degradation pathways of DOX were explored in this study. Finally, a novel continuous flow reactor was designed, featuring a unique design that ensures full contact between wastewater and the composite electrodes, thereby achieving continuous and efficient treatment of antibiotic wastewater.

Development of biomass aerogels with aligned channels: For continuous treatment of oily wastewater and solar-powered oil evaporation

A biomass CS/CNTs@MTMS (MCCS) aerogel with both aligned channel network, superhydrophobicity, and photothermal conversion ability was prepared by a green and facile strategy of directed freeze-drying and chemical vapor deposition using chitosan (CS), carbon nanotubes (CNTs), and methyltrimethoxysilane (MTMS) as the building materials. Capacity to adsorb a large variety of oils and organic solvents, with an adsorption capacity of up to 34–83 g/g. After 10 cycles, the adsorption capacity of MCCS remained at 94 % of the initial capacity, providing excellent reusability. In addition, due to its unique network of aligned channels, the MCCS can continuously separate oil and water, making it a sustainable oil–water separator. More interestingly, the MCCS aerogel has excellent photothermal conversion capabilities, and it was utilized to evaporate oil collected during the oil–water separation process using solar energy. This work provides an opportunity to design novel self-cleaning photothermally driven oil–water separation biomass materials with superhydrophobicity-strong lipophilicity.

Continuous peroxymonosufate activation for antibiotics degradation via fluorine-free-Ti3C2Tx-CoFe2O4 hydrogel beads: Performance, mechanism and application

This study explored the efficient, stable, and continuous treatment of antibiotic-containing wastewater through rapid electron transfer between layered fluorine-free Ti3C2Tx and CoFe2O4 nanomicrospheres. These materials were synthesized into hydrogel beads crosslinked with sodium alginate, resulting high reactivity and stability. Ff-Ti3C2Tx-CoFe2O4 catalyst facilitated peroxymonosufate (PMS) activation through rapid electron transfer and the formation of Ff-Ti3C2Tx-CoFe2O4-PMS* species, as confirmed by experiments and DFT calculations. The cleavage of the S-O bond on Ff-Ti3C2Tx-CoFe2O4 catalyst identified as the primary mechanism for the generation of singlet oxygen (1O2). In a continuous flow system, the degradation efficiency of antibiotics, such as sulfamethoxazole (SMX), remained above 96.9 % with ultra-low metal leaching (<1.3 μg·L−1, 72 h). This research provides significant insights into the practical application of PMS activation for antibiotic degradation, offering a sustainable solution for wastewater treatment.

Performance and mechanic insights into potassium-oxygen co-doping graphic carbon nitride for UV photocatalytic oxidation of carbamazepine

Graphitic carbon nitride (g-C3N4) has good prospect in the field of photocatalysis, but its small specific surface area and low photogenerated carrier separation efficiency limit the large-scale application in photocatalytic wastewater treatment. In this study, the one-step thermal polymerization method was employed to synthesize potassium and oxygen co-doped g-C3N4 (OCN-3), which was used in photocatalytic degradation of carbamazepine (CBZ). Compared with the original g-C3N4, the pseudo first-order kinetic constant of CBZ degradation by OCN-3 was increased from 0.00820 min−1 to 0.17529 min−1 under UV irradiation. The results of competitive oxidation kinetics experiment demonstrated that ·OH played a main role in CBZ degradation. The photoelectric experiments and calculation based on density functional theory revealed that potassium and oxygen atoms can not only regulate the local electron density, but also reduce the band gap width and promote electron transfer as well as photogenerated carrier separation. Furthermore, OCN-3 was loaded on carbon cloth to prepare supported photocatalyst, which can be conveniently applied in continuous wastewater treatment reactor, and the results shows that the degradation efficiency of CBZ remains over 90% within 600 min continuous operation when the hydraulic retention time was 1.25 h.

Efficient adsorption performance and mechanism of fluoroquinolone antibiotic onto the acid wash-assisted Co NPs/N-C adsorbent

In this study, ZIF-67 was employed as a template, and applied a novel combined treatment method of thermal and acid treatment to provide rapid mass transfer channels and additional adsorption sites for pollutant molecules, thus achieving high adsorption capacity and shorter adsorption time. The adsorption of Co NPs/N-C on ciprofloxacin reached equilibrium within 70 min with a maximum adsorption capacity of 486.20 mg·g−1. Furthermore, the adsorption capacity was enhanced by 1.9 times after acid-wash. The fitted data indicated that the pseudo-second-order kinetics model could more accurately describe the adsorption process, with intraparticle diffusion and liquid film diffusion jointly determining the adsorption rate, primarily involving chemical adsorption. The Langmuir model best described the antibiotic adsorption isotherm, indicating monolayer adsorption on Co NPs/N-C. Based on various characterizations before and after adsorption, it was confirmed that antibiotics were adsorbed onto Co NPs/N-C through hydrogen bonding and π-π interactions. Additionally, this adsorbent exhibited strong continuous treatment capability, a simple and efficient desorption method, as well as efficient treatment efficiency for actual water bodies. This study suggests that Co NPs/N-C can be considered an efficient and promising adsorbent, and the proposed strategy can potentially serve as an antibiotic adsorbent for continuous wastewater treatment.

Flexible bifunctional wood-derived water filtration/photo-Fenton membrane for efficient purification of mixed organic wastewater

Membrane filtration technology demonstrates excellent continuous processing capability in organic wastewater treated processes, which is usually applied in continuous industrial processes. However, it still faces a contradiction between membrane flux and treatment efficiency. In this study, a flexible wood-based photocatalytic membrane with high membrane flux and exceptional photofenton performance was developed via partial fragment wood components and uniform loading of multi-metal oxide nanocatalysts, which breaks mentioned contradiction. The homogeneous and efficient wood-based dual-function water filtration/photofenton system was established by leveraging the directional porous structure of wood in conjunction with the nanocatalysts while adjusting their ratios, enabling effective purification of highly concentrated mixed organic wastewater. Under one solar intensity and negative pressure filtration (0.03 MPa), the system treated a mixed solution containing Rhodamine B, phenol, and tetracycline at a concentration of 280 mg L−1 with the removal efficiencies of 100 %, 93.4 %, and 90.2 %, respectively, and the membrane flux could up to 315.3 Lm−2 h−1 within one hour. The membrane showed a good recycling performance, and the decay rates were all below 5 % after five cycles. This wood-based dual-function water filtration/photo-Fenton system provides a new approach for the continuous dynamic treatment of high-concentration organic wastewater on an industrial scale.

Ultra-efficient decontamination via functionalized reactive electrochemical membrane for peroxymonosulfate activation: High water flux with extremely low energy consumption

A perovskite LaCoO3 functionalized Ti4O7 reactive electrochemical membrane (REM) was developed for electro-enhanced peroxymonosulfate (PMS) activation (E-REM-PMS), addressing limitations in wastewater treatment efficiency, reusability, and interference resistance. It achieved 100% carbamazepine (CBZ) removal at a rate constant of 39.69 min−1, 233 and 23 times of electro-REM (E-REM) system without PMS and REM-PMS system without electricity. In-situ Fourier transform infrared spectroscopy (FTIR) highlighted the promotion of electro-activation on PMS, while density functional theory (DFT) calculations elucidated mechanism differences under three adsorption configurations. 1O2 (2.97×10−9 M), SO4•− (2.09×10−11 M) and •OH (7.36×10−12 M) dominated the E-REM-PMS system, consistent with sequence of reactive species by DFT results. Continuous treatment of pharmaceutical wastewater confirmed 100% CBZ removal and 60%-70% TOC mineralization at ultrahigh water flux (642.86 L/m2·h) with minimal energy consumption (0.01 kWh/m3·order). This work proposed a high-performance and anti-fouling REM, offering an efficient and economical solution for wastewater treatment.

Optimization of TiO2/ACF Photocatalytic Continuous Treatment of MB Wastewater Based on Response Surface Methodology

Optimization of TiO2/ACF Photocatalytic Continuous Treatment of MB Wastewater Based on Response Surface Methodology

Utilization of native Chlorella strain in laboratory-scale raceway reactor for synthetic wastewater treatment: A study in batch and continuous modes with multi-substrate modeling

Despite of the possibility to include microalgae in civil wastewater treatment process, the practice is still not common due to the lack of available instruments to implement it. In this study, a straightforward comprehensive approach for dealing with microalgal wastewater treatment involving an original kinetic model is proposed. A first set of batch cultures of a native strain of Chlorella was firstly carried out to obtain the kinetic parameters: maximum growth factor (μmax) and half-saturation constant (Ks), for each limiting nutrient. Maximum growth factor values of 0.0279 for PO43−, 0.0319 h−1 for NH4+, 0.0352 h−1 for glucose, and 0.0263 h−1 for the overall medium were found. Regarding the Ks, values of 1.08 mg L−1, 27.70 mg L−1, 1.34 mg L−1, were found for PO43−, NH4+ and glucose respectively, and a value of 2.8 % of the total nutrients for the overall medium. These parameters were used to set a multi-substrate kinetic model able to predict the growth in batch and in continuous operation within a laboratory scale raceway reactor. The removal capabilities of the microalgae for each addressed pollutant were evaluated in a batch system and in a continuous system at dilution rates of 0.0025, 0.005, 0.01 and 0.015 h−1. This comprehensive approach represents a significant step towards addressing the continuous treatment of wastewater utilizing microalgae.

Coupled Photocatalysis and Microalgal–Bacterial Synergy System for Continuously Treating Aquaculture Wastewater Containing Real Phthalate Esters

We developed a system combining visible-light photocatalysis with biological treatment for the continuous removal of phthalate esters (PAEs) from both synthetic and real aquaculture wastewater. We investigated the effects of different operating factors, including the coexistence of glucose or PAEs, on individual PAE removal by using a photobiological system (PBS). In wastewater containing a mixture of PAEs, that is, containing di-(2-ethylhexyl)phthalate (DEHP), dibutyl phthalate (DBP), and dimethyl phthalate (DMP), a coimmobilized bioreactor system comprising the bacterium Pseudomonas putida and the microalga Chlorella vulgaris demonstrated a higher removal efficiency than immobilized P. putida alone or a coculture of immobilized P. putida and suspended C. vulgaris did. The PBS employed for the continuous treatment of real aquaculture wastewater containing DEHP (0.62 ± 0.05 mg/L), DBP (8.7 ± 0.9 mg/L), and DMP (17.4 ± 1.5 mg/L) achieved at least 99.5% PAE removal and 99.2% mineralization efficiency under optimal operating conditions. After 42 days of treatment, inoculated Pseudomonas (98.12%) remained the predominant genus in the bioreactor. The results reveal that the symbiotic microalgal–bacterial system is a feasible alternative to a pure P. putida immobilized bioreactor for reducing CO2 emissions from mineralized PAEs through microalgal activity.

Synergy of rapid adsorption and photo-Fenton-like degradation in CoFe-MOF/TiO2/PVDF composite membrane for efficient removal of antibiotics from water

The reasonable construction of composite membranes with dual functions of rapid adsorption and photo-Fenton-like oxidation degradation holds great significance in the field of wastewater purification. Herein, a poly(vinylidene fluoride)-based composite membrane (denoted as CFT/PVDF) was meticulously prepared through a nonsolvent induced phase separation (NIPS) process with the introduction of cobalt-iron metal–organic framework (CoFe-MOF) and TiO2 (Degussa P25). The composite membrane exhibited an excellent adsorption ability for removing a variety of organic pollutants from water. With the integration of adsorptive filtration and in situ photo-Fenton-like degradation, the removal efficiency of tetracycline hydrochloride reached up to 92.9% through the CFT/PVDF membrane in one filtration process, and the remarkable performance could be maintained after ten consecutive cycles. Moreover, a group of CFT/PVDF membranes was connected in series to realize the fast and continuous wastewater treatment. The photo-Fenton-like oxidation mechanism and possible degradation pathways were proposed on the basis of active-species detections and degradation intermediates analysis. The toxicological analysis indicated that tetracycline was in situ degraded into less toxic intermediates and even nontoxic substances by the CFT/PVDF composite membrane. This work provides some valuable guidance on the construction of self-cleaning membranes for sustainable wastewater remediation and potential applications.

Continuous Treatment of Refractory Wastewater from Research and Teaching Laboratories via Supercritical Water Oxidation–Experimental Results and Modeling

Teaching and research laboratories generate wastes of various compositions and volumes, ranging from diluted aqueous solutions to concentrated ones, which, due to milder self-regulation waste-management policies, are carelessly discarded, with little attention given to the consequences for the environment and human health. In this sense, the current study proposes the application of the supercritical water oxidation (SCWO) process for the treatment of complex refractory wastewater generated in research and teaching laboratories of universities. The SCWO, which uses water in conditions above its critical point (T &gt; 647.1 K, p &gt; 22.1 MPa), is regarded as an environmentally neutral process, uniquely adequate for the degradation of highly toxic and bio-refractory organic compounds. Initially, the wastewater samples were characterized via headspace gas chromatography coupled with mass spectrometry. Then, using a continuous tubular reactor, the selected operational parameters were optimized by a Taguchi L9 experimental design, aiming to maximize the total organic carbon reduction. Under optimized conditions—that is, temperature of 823.15 K, feed flow rate of 10 mL min−1, oxidizing ratio of 1.5 (50% excess over the oxygen stoichiometric ratio), and sample concentration of 30%—TOC, COD, and BOD reductions of 99.9%. 91.5% and 99.2% were achieved, respectively. During the treatment process, only CO2, methane, and hydrogen were identified in the gaseous phase. Furthermore, the developed methodology was applied for the treatment of wastewater samples generated in another research laboratory and a TOC reduction of 99.5% was achieved, reinforcing the process’s robustness. A thermodynamic analysis of SCWO treatment of laboratory wastewater under isothermal conditions was performed, using the Gibbs energy minimization methodology with the aid of the GAMS® 23.9.5. (General Algebraic Modeling System) software and the CONOPT 4 solver. Therefore, the results showed that SCWO could be efficiently applied for the treatment of wastewater generated by different teaching and research laboratories without the production of harmful gases and the addition of hazardous chemicals.

Efficient electrochemical degradation of congo red dye by Pt/CuNPs electrode with its attractive performance, energy consumption, and mechanism: Experimental and theoretical approaches

Clean and sustainable sources of drinkable water require continuous wastewater treatment. In this study, a thin film of copper nanoparticles (CuNPs) was simply electrodeposited using the cyclic voltammetry technique (CV) on the Pt electrode, and its electrocatalytic activity toward the electro-degradation of Congo red (CR) dye was observed. The CuNPs were characterized using Ultraviolet-Visible (UV–Vis) spectroscopy, Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray (EDX), Transmission Electron Microscopy (TEM), and X-Ray Diffraction (XRD). The electrochemical degradation process was performed using chronoamperometry measurements (CA) in 0.25 M KCl at a pH of 7.5 at room temperature. At the optimum parameters, the CR degradation followed a pseudo-second order. A computational study using Density Functional Theory (DFT) with Lee/Yang/Parr (B3LYP) level, 6–311++ G(d,p), as the basis function set calculation, to find the quantum parameters. The findings demonstrated good agreement between the theoretically derived mechanism and the experimentally proposed mechanism. So, the local Fukui indices were used to confirm this mechanism. Larger values for the nitrogen atoms that make up the CR dye were revealed by the latter, confirming that these locations are the most vulnerable to radical attacks. The proposed modified Pt/CuNPs electrode reflects an excellent recovery in wastewater samples in the range of 95–104 %. The modified electrode developed reflects high reducibility and reusability.

Shape stability control of a 3D-printed clay/biochar-based monolith to support Fe catalyst for continuous levofloxacin degradation with low metal leaching

Disposing of wet solid waste sludge has become a prominent issue because it has high environmental risks. Herein, a clay/biochar-based monolith (CBM) is prepared using a three-dimensional (3D) printing design method. The CBM is loaded with iron (Fe) and used as a catalyst (Fe/CBM) to activate peroxymonosulfate (PMS) for degrading levofloxacin (LVF) in an aqueous solution. The monolith preparation process is inexpensive, and the monolith has designable flow paths that facilitate improved mass transport and material recycling. ZnCl2, as a chemical activator, is added to the 3D-printed slurry to improve the catalytic performance of Fe/CBM. Oscillatory stress sweep and frequency sweep tests prove that incorporating ZnCl2-containing sludge in the slurry effectively increases the elastic modulus and critical stress, improving structural stability and constructability. The slurry containing 10% sludge (S10%-Zn with 1 M ZnCl2), exhibits 30% higher static yield stress than the slurry containing only clay and water (S0%). Fe/CBM is prepared by loading Fe active sites onto the surface of CBM via an impregnation method, and it leaches very low amounts of Fe (<0.2 mg/L) and other heavy metals (e.g., Cd, and Pd, etc). Fe/CBM-S10%-Zn/PMS with 10% mass fraction of sludge exhibits much higher (∼80% at 20 min) degradation efficiency than Fe/CBM-S0%/PMS (∼15% at 20 min) and Fe/CBM-S10%/PMS (∼43% at 20 min). Combining with XPS results, when ZnCl2 is added to the slurry, the content of Fe2+ in the catalytic material increases, improving the catalytic performance. The PMS activation mechanism of Fe/CBM-S10%-Zn for LVF degradation is also discussed, which is ascribed to the radical and nonradical pathways. This provides new insights on how to recycle solid waste and make high-performance clay/biochar-based monolith catalysts for the continuous wastewater treatment.

Enhanced salt removal performance using nickel hexacyanoferrate/carbon nanotubes as flow cathode in asymmetric flow electrode capacitive deionization

One of the most widely used CDI processes is flow electrode capacitive deionization (FCDI), which is preferred over conventional CDI with static electrode due to its continuous treatment of high-salt wastewater and ability to scale production. However, the discontinuous charge transport network in flow electrodes restricts the improvement of desalination performance. In this study, we prepared nickel hexacyanoferrate and carbon nanotubes composites (NiHCF@CNTs) by a simple ball-milling method and constructed an asymmetric FCDI (AFCDI) system using NiHCF@CNTs and AC as flow cathode and anode, respectively. Then the desalination performance of AFCDI was examined and compared with that of symmetric FCDI system using AC as both flow electrodes under different conditions. The stability was also investigated by a 20-cycle operation test. It was found that AFCDI system showed higher average salt removal rate and lower energy consumption compared with FCDI, owing to the enhancement of charge transport resulting from the couple of high specific capacitance of NiHCF and excellent electrical conductivity of CNTs. Moreover, AFCDI system has stable desalination performance in continuous operation. These results indicate that compositing Faradic materials and CNTs is an effective strategy for improving desalination performance of FCDI.

Tri-modified ferric alginate gel with high regenerative properties catalysts for efficient degradation of rhodamine B

Water pollution caused by dyes has become a focal point of attention. Among them, the heterogeneous Fenton reaction has emerged as an effective solution to this problem. In this study, we designed a ferric alginate gel (PAGM) tri-modified with poly(vinyl alcohol), graphene oxide, and MoS2 as a heterogeneous Fenton catalyst for organic dye degradation. PAGM addresses the drawbacks of alginate gel, such as poor mechanical properties and gel chain dissolution, thereby significantly extending the catalyst's lifespan. The removal rate of rhodamine B by PAGM reached 95.5 % within 15 min, which was 5.9 times higher than that of unmodified ferric alginate gel. Furthermore, due to the π–π interactions, PAGM exhibits unique adsorption properties for pollutants containing benzene rings. Additionally, PAGM can be regenerated multiple times through a simple soaking procedure without any performance degradation. Finally, the reaction column constructed with PAGM maintained an 83.5 % removal rate even after 319 h of continuous wastewater treatment. This work introduces a novel concept for the study of alginate-based gel catalysts in heterogeneous Fenton reactions.

Mechanosynthesis preparation of controlled-composite particles for sorption and photo-oxidation applications

Activated carbon/TiO2 composites are a solution to manage solar discontinuities, especially for continuous wastewater treatment applications. Mechanical milling has recently shown its potential to develop AC/TiO2 composite powders. This work aims to highlight the possibility of controlling and modulating the spatial distribution of the adsorbent and photocatalyst within the composite structure. Here, our objective is to develop composites with core–shell structure where AC core is covered with photocatalyst. Spatial distribution of the component was controlled by modulating the elaboration procedures through mechanical grinding. They lead to the composite structure whose sorption and photocatalytic properties are preserved and identical to those of the constituents alone. Thus, these core–shell composites offer a double functionality: (i) accessibility to adsorption sites of the adsorbent material and (ii) a maximum light harvesting by the photocatalyst.