Phenol Removal Rate Research Articles

Controllable Synthesis of BixOyBrz/TiO2 Heterojunctions with Excellent Visible‐Light‐Driven Photocatalytic Activities for Phenol

AbstractBixOyBrz/TiO2 composites have been synthesized by hydrothermal method, with TiO2 nanoparticles being employed as substrate. During the process of hydrothermal reaction, both temperature and pH have been utilized to effectively regulate the Bi/Br atomic ratio of BixOyBrz/TiO2 composites. In essence, the competitive reaction between OH− and Br− in the solution is the key factor to form BixOyBrz with different Bi/Br atomic ratios. Under visible light, the prepared Bi4O5Br2/TiO2 heterojunction demonstrates higher photocatalytic activity than other BixOyBrz/TiO2 composites for phenol and Rh B. The removal rate of phenol with Bi4O5Br2/TiO2 heterojunction is up to 92.1% after irradiation for 75 min. The excellent photocatalytic activities of Bi4O5Br2/TiO2 heterojunction are mainly attributed to its optimized microstructure and the matching band energy structure, whereby TiO2 nanoparticles with ≈10 nm diameter uniformly arranged on ≈10.2 nm thick Bi4O5Br2 nanosheets. Moreover, the heterojunction structure promotes the separation of photo‐generated electrons and holes in Bi4O5Br2/TiO2, while and h+ are the main active species during its photocatalytic processes.

A self-sufficient catalytic nanofiber evaporator for solar-driven efficient water purification through in-situ hydrogen peroxide generation

Solar-driven interfacial water evaporation (SDIWE) is an emerging technology for the production of clean water driven by inexhaustible energy source, but its application suffers from volatile organic compounds (VOCs) escaping into condensate water. Herein, a bifunctional SDIWE system integrated with Fenton process was proposed to achieve self-sufficient (not adding any additional chemicals to feed water) high-quality freshwater production from VOCs-contained wastewater through in-situ hydrogen peroxide (H2O2) generation. The hybrid SDIWE system based on AgNPs (Ag nanoparticles)@graphitic carbon nitride (g-C3N4)/beta-iron hydroxide oxide (β-FeOOH)-Polyacrylonitrile (AgG/Fe-PAN) nanofiber membrane exhibited an excellent evaporation performance (1.61 kg m-2h−1) under one sun (1 kW m−2). Significantly, in the absence of external oxidant source, the phenol removal rate in condensate water reached 98.4 ± 0.2 % due to the synergic photocatalysis technology and Fenton reaction, which was 6.1 times that of sole SDIWE (16.2 ± 0.5 %). Mechanism analysis reveals that H2O2 was effectively in-situ generated by AgNPs@g-C3N4 particles (∼18.8 μM at 4 h). Subsequently, the produced H2O2 was further activated to •OH radicals via β-FeOOH that ensures the VOCs decomposition during rapid steam generation. Meanwhile, the hybrid system not only exhibited an excellent phenol removal rate of 91.6 ± 0.6 % in wide pH ranges (1–11), but also ensured a good removal performance for various organic pollutants and excellent antibacterial properties. To sum up, the hybrid system has successfully integrated SDIWE technology with various advanced oxidation processes (AOPs), providing a novel way for the pollution-free production of high-quality clean water during the SDIWE process for water purification.

Porous fluorine-cerium nanosheets anchored with FeOOH quantum dots for synergistic enhanced visible-light-driven photo-Fenton degradation of phenol

The utilization of two-dimensional (2D) materials to construct heterogeneous catalysts provides opportunities for environmental remediation, while the incorporation of porous structures can further enhance catalytic performance. In this work, a porous 2D FeOOH/fluorine-cerium (F-Ce) nanosheet composite was designed and synthesized by a simple impregnation-precipitation method. The unique 2D porous structure of F-Ce promoted the high dispersion of FeOOH quantum dots (QDs) (∼1.4 nm) and their tight integration to form S-scheme heterojunctions. This structure offered a greater number of active sites, and significantly improved the capacity of light absorption and the separation and migration efficiency of photogenerated carriers, thus improving catalytic activity. This catalyst achieved a phenol removal rate of 98.1 % within 20 min during the photo-Fenton reaction, which significantly surpasses pure FeOOH (32.9 %) and F-Ce (21.7 %) alone. In particular, the optimized 14FeOOH/F-Ce catalyst achieved more than 95.0 % degradation efficiency within a remarkably short period of 5 min. Mott Schottky and in situ irradiated X-ray photoelectron spectroscopy (ISI-XPS) studies demonstrated that the S-scheme charge transfer mechanism of this heterojunction synergistically enhanced the catalytic activity of the Fenton-like reaction. This study provides valuable insights for designing efficient 2D porous heterojunction catalysts for visible-light-driven Fenton applications.

Treatment of high-concentration semi-coke wastewater by phenolic condensation and persulfate oxidation

In this study, the combined process of phenolic condensation-persulfate(PS) advanced oxidation was adopted to treat semi-coking wastewater. Using the phenolic condensation method as a pretreatment unit to remove phenolic substances for the preparation of phenol-formaldehyde resins, and using an aerated/PS/pyrite oxidation system as a deep treatment unit to remove chemical oxygen demand (COD) and ammonia nitrogen (NH3-N) from the wastewater. Analysis and characterization of phenol-formaldehyde resin, organic compounds in wastewater, and pyrite using FT-IR, TG-DTG, GC-MS, and XPS techniques. The results showed that under the conditions of adding 1.8vt % formaldehyde, pH 10.5, reaction temperature 95 ℃ and reaction time 3 h, the removal rates of volatile phenol, COD and NH3-N in semi-coke wastewater were 97.54 %, 41.14 % and 56.50 %, and the yield of phenolic resin was 6.62 g/L. Subsequently, treated with an aerated/PS/pyrite system, the PS concentration 0.4 mol/L, the pyrite dosage 15 g/L, the pH 3, the temperature 65 ℃, and the aeration 3 h, the removal rates of COD and NH3-N are 99.20 % and 86.80 %. In the phenolic condensation process, phenolic substances in semi-coke wastewater generate phenoxy anions under the influence of OH-, which undergo addition reactions with formaldehyde to produce hydroxymethyl phenol. Hydroxymethyl phenol further undergoes condensation reactions with other phenolic substances and itself to form phenolic resin, while amide compounds are generated through reactions between ammonia nitrogen and carboxylic acid substances. In the aeration/PS/pyrite system, Fe2+ released from pyrite oxidation activates PS to produce SO4•− and O2•−. The contribution of free radical oxidation and decomposition of pollutants such as phenols, amides, and NH3-N in wastewater is 84.60 %. Specifically, SO4•− oxidation contributes 61.54 %, while O2•− accounts for 22.21 %. Amide compounds and phenolic substances in the wastewater are oxidized, leading to ring opening and chain scission, resulting in the formation of alkane compounds.

Assistance of aminated straw on enhanced biodegradation of phenol through bacteria and potential prediction of machine learning for bioremediation

ABSTRACT How to treat phenol-containing wastewater harmlessly is an urgent problem to be solved. In this study, a kind of biomaterial was prepared through strain PAO1 immobilized on aminated straw to enhance the phenol removal rate and efficiency. The aminated straw assisted PAO1 to increase the phenol degraded concentration from 1,900 to 1,500 mg/L, and shorten the degraded time by 44 h at 1,500 mg/L phenol. The immobilized PAO1 could remove phenol at pH 10 and 11, which was 2.7 and 3.8 times higher than free bacteria, respectively. In addition, the immobilized PAO1 could totally remove phenol, which was twice as high as that of free bacteria, at 4% NaCl stress. Furthermore, the removal efficiency of immobilized PAO1 was higher than that of free bacteria under the stress of various metal ions, especially for Co2+ and Pb2+. The determination coefficients R2 and root mean square error showed that the back propagation artificial neural network model could predict the degradation of phenol under various conditions, saving time and economic cost. The present study envisions that this biomaterial has great potential in the bioremediation of organic pollutions.

Photoactivation of sulfite by FeTiO3 for organic pollutant degradation: Performance and mechanism

In recent years, the exploration of sulfite (S(IV))-based advanced oxidation processes has attracted increasing attention due to its high performance in the degradation of aqueous organic contaminants. In this study, we investigated the activation of S(IV) by ilmenite (FeTiO3) under photo irradiation using phenol as a substrate. The FeTiO3/S(IV)/photo system demonstrated a remarkable phenol removal rate, achieving 81.4 % degradation within 30 min under optimal conditions. The photocatalytic mechanism involves the generation of electron-hole pairs in FeTiO3, with photogenerated holes activating the adsorbed S(IV) on the catalyst’s surface to produce various free radicals, among which SO4− is identified as the primary active species. Density functional theory calculations further suggest that electron transfer between ilmenite and S(IV) may occur via a Fe-O-S bridge. Additionally, the approach demonstrates satisfactory reusability of the photocatalyst and consistent effectiveness in real-water matrices. This study contributes to the development of more efficient, cost-effective, and environmentally friendly water treatment strategies by providing a deeper understanding of the proposed FeTiO3/S(IV)/photo system.

The dual role of biochar in boosting phenol biodegradation and anti-inhibition performance against hazardous substrate

Enhancing the biodegradation of hazardous recalcitrant organic compounds from wastewater has garnered increasing attention. Herein, bamboo biochar was screened for subsequent investigation as it considerably enhanced hazardous phenol removal efficiency by 125.68 % over the biochar-free system at 700 mg/L. Besides, the influencing factors were optimized, including biochar dosage and phenol concentration. However, the phenol removal rate decreased by 75.91 % within 15 hours when utilizing biochar oxidized by H2O2, perhaps due to eliminating aromatic clusters on biochar. Combined with FTIR analysis, CO and -OH on aromatic clusters of biochar were recognized as the underlying contributors to facilitating electron transfer in phenol biodegradation. Furthermore, the ortho-disubstituted benzene ring was discovered on biochar, which may originate from catechol, an intermediate during phenol degradation, suggesting that biochar also serves as a site for phenol biodegradation. Moreover, the fabricated biochar-sodium alginate microspheres enhanced anti-inhibition to phenol over suspended bacteria by 192.15 %. The system also eliminated 99.93 % of phenol after the seven recycles at 1258.75 mg/L, exhibiting excellent reusability. This work provides valuable insights into bioaugmentation strategies for bio-degrading phenol using biochar.

Efficient degradation of phenol wastewater using CuFe2O4 as highly active catalyst in the microwave-assisted catalytic wet peroxide oxidation process

Six kinds of CuFe2O4, including capsule-shaped CuFe2O4-C, plate-shaped CuFe2O4-P, polyhedral-shaped CuFe2O4-O, and irregular shaped catalysts prepared by co-precipitation (CuFe2O4-CO), by microwave heating (CuFe2O4-MW), and by hydrothermal synthesis (CuFe2O4-S), were used in the microwave-assisted catalytic wet peroxide oxidation (MW-CWPO) process to remove phenol from wastewater. The physicochemical properties of the catalysts were dependent on preparation methods. The catalytic activities were in the order of CuFe2O4-CO (95.3 %) >> CuFe2O4-P (78.8 %) > CuFe2O4-C (72.7 %) > CuFe2O4-MW (67.1 %) > CuFe2O4-S (63.3 %) > CuFe2O4-O (60.0 %). Effects of CuFe2O4-CO dosage, H2O2, pH, phenol initial concentration, anions, and MW in the MW-CWPO process were then systematically studied. Under optimal conditions of pH = 3, H2O2 = 1 mL/L, and CuFe2O4-CO = 0.5 g/L, MW energy of 99 kJ (550 W, 3 min) and 132 kJ (550 W, 4 min) were found essential to achieve 99.6 % removal rate of phenol and 95.3 % removal rate of chemical oxygen demand (COD). Possible degradation pathways were suggested: phenol was firstly oxidized into hydroquinone and catechol, which further degraded into p-benzoquinone, 1,2-benzoquinone, respectively. Finally, these compounds transformed into oxalic acid, CO2, and H2O within 4 min. The proposed mechanism suggested that the catalyst CuFe2O4-CO generates more “hot spots” due to its irregular shape, which enhances MW scattering and absorbing abilities. Consequently, the chemical composition and crystal structure of the catalyst significantly promote the decomposition of H2O2 to generate free radicals. The CuFe2O4-CO has an opportunity of potential engineering application due to its high efficiency and stability.

New understanding of the main active substances and the promotion mechanism in the degradation of phenol by Fe–C micro-electrolysis systems

ABSTRACT The mechanism of phenol degradation by micro-electrolytic systems can be fully understood by evaluating the oxidation of active substances from the two aspects of phenol bond-breaking and mineralization, and the direction of promoting the generation of active substances is pointed out. In this article, the effects of H2O2, O2-•, ·OH and 1O2 in the degradation of phenol were analyzed using phenol and chemical oxygen demand (COD) removal rates as judgment indicators, respectively. And the addition of C6O8H6 to the micro-electrolysis system was adopted to promote the generation of active substances. The experimental results showed that the active substances which played a dominant effect in the process of phenol bond-breaking and mineralization were changed. While 1O2 is dominant in the bond-breaking of phenol, •OH is dominant in the mineralization of phenol. After adding C6O8H6 (1 mmol/L), the removal rates of phenol and COD were increased by 7.35 and 4.85%, respectively. This was attributed to the autoxidation reaction of C6O8H6 and the continuous supply of H+ while reducing Fe3+ to Fe2+. Additionally, the C6O8H6 regulated the reaction pathway to improve the utilization of H2O2. This study provides a new perspective for the understanding of active substances in micro-electrolysis systems.

Optimized electrochemical treatment of semi-coking wastewater for enhanced degradation of biological toxicity using a Ru-Ir-Ti anode and Co-Ti cathode

The Co-Ti cathode was prepared to reduce the biological toxicity of semi-coke wastewater by electrochemical system with commercial ruthenium-iridium titanium (Ru-Ir-Ti) anode. Meanwhile, the removal rate of chemical oxygen demand (COD), volatile phenol (VP) and ammonia nitrogen (NH3-N) in wastewater were also evaluated. Hence, the influence of processing time (A), dilution multiple (B), initial pH (C), electrolyte concentration (D) and current density (D) were systematic explored. After treatment, with the optimized experiment condition of processing time (150 min), dilution multiple (300 times), initial pH (3.2), electrolyte concentration (0.15 mol/L), current density (16 mV/cm2), the B/C value of wastewater was greatly improved from 0.12 to 0.31, the removal rate of COD, NH3-N and VP was 96.82 %, 92.34 % and 97.07 %, respectively. The sequence of significance was B>D>E*E>B*D>A*D>D*D. This most effective degradation was owing to the simultaneously oxidization of both cathode and anode, turning the highly biological toxic wastewater to the biodegradable one. The direct oxidation reaction happened on anode, furthermore, the indirect oxidation reaction would be accelerated near the cathode because of active free radicals generation such as ·OH and O2•– when the cobalt’s valence changed from +2 to +3. It deserve to be mentioned in this research is that the direct and indirect oxidation simultaneously contributed to the degradation of biological toxicity, which is great beneficial for the further bio-chemical processing.

Coupled treatment of aniline and phenol in water by electrochemical copolymerization

ABSTRACT Anilines and phenols are recognized as challenging organic pollutants in industrial wastewater. Herein, the coupled treatment of aniline and phenol in water was achieved through electrochemical oxidation-induced copolymerization. After the electrolysis (1,300 mA for 10 h) in the solution of aniline and phenol (200 mL, each at a concentration of 5 g/L), the organic compounds were efficiently precipitated from their mixed solution by copolymerization. These insoluble copolymers could be easily separated by filtration and collected as brown powders, and the average removal rate of aniline and phenol was calculated as 0.6 mol/h m2 in this coupled electrolysis. The chemical oxygen demand (COD) test of the filtrates showed that it reached up to 98% of the COD removal ratio. Moreover, mixed solutions containing multiple aniline and phenol derivatives were also applicable for this coupled treatment strategy, and they were efficiently removed together after electrolysis.

Excellent phenol removal ability of Acinetobacter guillouiae BY18 under different inorganic nitrogen conditions

Phenol and inorganic nitrogen generally exist in industrial wastewater and contaminated soil. In this study, Acinetobacter guillouiae BY18, which can simultaneously remove high concentrations of phenol and inorganic nitrogen, was isolated from a wet meadow in Weining County, Guizhou Province, China. The optimal remediation conditions for strain BY18 were 25 °C and pH 7.20–8.20, with a C/N ratio of 10, rotation speed of 150 r/min, and inoculation amount of 0.2×108 CFU. When phenol and ammonium were both present, strain BY18 could remove 982.86 mg/L of phenol and 64.76 mg/L of ammonium within 18 h. Strain BY18 was able to eliminate 979.71 mg/L, 55.84 mg/L, and 49.20 mg/L of phenol, nitrite, and nitrate, respectively, within 36 h when ammonium was substituted by nitrate or nitrite. In the simultaneous nitrification and denitrification reaction system, the maximum removal rates of phenol and ammonium were 92.53 mg/(L·h) and 5.7 mg/(L·h), respectively. Overall, strain BY18 had a remarkable phenol removal ability under different inorganic nitrogen conditions.

Hexagonal boron nitride-doped carbon membrane as anode for the enhanced adsorption and electrochemical oxidation of phenol

An activated carbon membrane (ACM) doped with hexagonal boron nitride (h-BN) was fabricated by using activated carbon as the raw material and phenolic resin as the binder. The preparation process involves blending raw materials, ball milling, membrane pressing, and high-temperature carbonization. The conductive ACM was employed as an anode to constitute an electrochemical membrane reactor (EMR) for phenol removal. The effect of h-BN doping rate (0–5 wt%) on the properties of ACM was explored. Results showed that ACM1 (1 wt% h-BN) displayed a small pore size (20 nm), high porosity (41.6 %), large specific surface area (446.8 m2/g), and strong mechanical strength (15.4 MPa) compared to the pristine ACM0. The oxygen precipitation potential of ACM1 (2.11 V) was much higher than that of ACM0 (1.53 V), thus reducing oxygen generation at the anode in EMR for phenol degradation. The phenol removal rate of phenol obtained from EMR with ACM1 as the anode at 1.5 V was up to 95.6 %, which was much higher than that for ACM0 (39.3 %). Density functional theory (DFT) calculations and experimental results confirmed that h-BN-doping enhanced the adsorption active sites, and adsorption energy, leading to the high performance of EMR for phenol removal. In addition, the equilibrium adsorption capacity of ACM1 (10.2 mg/g) was much higher than that of ACM0 (3.7 mg/g). The C atoms adjacent to pyridine N in ACM1 were identified as the adsorption and active catalytic sites by X-ray photoelectron spectroscopy (XPS) and DFT calculations. Therefore, this study sheds light on the design and fabrication of conductive carbon membranes for enhanced performance in industrial wastewater treatment.

Weak magnetic field and coexisting ions accelerate phenol removal by ZVI/H2O2 system: Their efficiency and mechanism

Human activity and industrial production have led to phenol becoming a significant risk factor. The proper treatment of phenol in wastewater is essential. In this study, the utilization of weak magnetic field (WMF) and zero-valent iron (ZVI) was proposed to activate H2O2 to degrade phenol contaminant. The results show that the weak magnetic field has greatly enhanced the reaction rate of ZVI/H2O2 removal of phenol. The removal rates of phenol by ZVI/H2O2/WMF generally decreased with increasing initial pH and phenol concentrations, and firstly increase and then decrease with increasing Fe0 or H2O2 dosage. When the initial pH is 5.0, ZVI concentration of 0.2 g L−1, H2O2 concentration of 6 mM, and phenol concentration of 100 mg L−1 were used, complete removal of phenol can be achieved within 180 min at 25 °C. The degradation process was consistent with the pseudo-first-order kinetic model when the experimental data was fitted. The ZVI/H2O2/WMF process exhibited a 1.05–2.66-fold enhancement in the removal rate of phenol under various conditions, surpassing its counterpart lacking WMF. It was noticed that the presence of 1–5 mM of Ca2+, Mg2+, Cl−, SO42− ions can significantly enhance the kinetics of phenol removal by ZVI/H2O2 system with or without WMF to 2.22–10.40-fold, but NO3−, CO32−, PO43− inhibited the reaction significantly in the following order: PO43− > CO32− > NO3−. Moreover, pre-magnetization for 3 min could enhance the ZVI/H2O2 process which was valuable in treatment of real wastewater. The hydroxyl radical has been identified as the primary radical species responsible for phenol degradation. The presence of WMF accelerates the corrosion rate of ZVI, thereby promoting the release of Fe2+ ions, which in turn induces an increased production of hydroxyl radicals and facilitates phenol degradation. The compounds hydroquinone, benzoquinone, catechol, maleic acid, and CO2 were identified using GC-MS, and degradation pathways were proposed. Employing WMF in combination with various ions like Ca2+, Mg2+, Cl−, SO42− is a novel method, which can enhance oxidation capacity of ZVI/H2O2 and may lead to economic benefit.

Enhanced heterogeneous Electro-Fenton catalysis using CNT/MoS2/FeCo-LDH cathode membranes for efficient phenol removal from wastewater

Herein, we innovatively crafted a novel CNT/MoS2/FeCo-LDH cathode membrane using a facile vacuum filtration method. Benefiting from the unique heterostructure between FeCo-LDH and MoS2, the prepared CNT/MoS2/FeCo-LDH cathode membranes catalyzed the production of high-concentration H2O2 (7.59 mg/L) at a low current density of 1.50 mA/cm2. The peak degradation efficiency of phenol (98.80%) was reached in only 60 min. Under optimized operating conditions, the phenol removal rate of the CNT/MoS2/FeCo-LDH cathode membrane remained above 80.00% within a wide pH range (3.0–9.0), demonstrating excellent adaptability. The synergistic incorporation of Mo, Fe, and Co ions facilitated additional chemical reaction pathways for Fenton-like reactions, thereby significantly enhancing hydrogen peroxide production. Notably, our approach exhibited moderate total organic carbon degradation efficiency, even for the actual pretreatment of coking wastewater, presenting a promising strategy for addressing recalcitrant industrial wastewater.

Phenol degradation and Sb(V) adsorption by superparamagnetic CTAB-modified iron calcium composite

The heavy metal ions and organic dyes in textile wastewater treatment pose a significant environmental burden and are challenging to effectively manage. A magnetic cationic surfactant hexadecyltrimethylammonium bromide (CTAB), modified iron-calcium composite (referred to as CIC), was prepared using a straightforward method from iron-calcium composites as raw materials. The simultaneous catalytic degradation and adsorption efficiency of phenol and Sb(V) from textile wastewater were evaluated using this material. The results indicate that under conditions of pH 5.0 and a duration of 180 min, both phenol and Sb(V) removal rates exceed 90%. Characterization and experimental findings reveal that CIC possesses magnetic properties, facilitating easy separation, and offers a large surface area, ensuring abundant adsorption sites and stability. Additionally, CIC can assist in the enhanced degradation of phenol by H2O2. Pseudo-second-order kinetics describe the adsorption of Sb(V) by CIC, while oxidative kinetics explain the degradation of phenol. The primary removal mechanisms involve the oxidation and degradation of phenol through the generation of hydroxyl radicals by H2O2 and the formation of Fe-O-Sb complexes between Sb(V) and the iron sites on CIC, as well as the precipitation of Ca-O-Sb compounds between Sb(V) and the calcium sites on CIC. Therefore, the synergistic effect of CIC and H2O2 offers an efficient and environmentally friendly method for the simultaneous removal of Sb(V) and phenol in coupled wastewater, presenting broad prospects for application in wastewater treatment.

Efficient flocculation pretreatment of coal gasification wastewater by halophilic bacterium Halovibrio variabilis TG-5.

The isolated halophilic bacterial strain Halovibrio variabilis TG-5 showed a good performance in the pretreatment of coal gasification wastewater. With the optimum culture conditions of pH = 7, a temperature of 46°C, and a salinity of 15%, the chemical oxygen demand and volatile phenol content of pretreated wastewater were decreased to 1721mg/L and 94mg/L, respectively. The removal rates of chemical oxygen demand and volatile phenol were over 90% and 70%, respectively. At the optimum salinity conditions of 15%, the total yield of intracellular compatible solutes and the extracellular transient released yield under hypotonic conditions were increased to 6.88g/L and 3.45g/L, respectively. The essential compatible solutes such as L-lysine, L-valine, and betaine were important in flocculation mechanism in wastewater pretreatment. This study provided a new method for pretreating coal gasification wastewater by halophilic microorganisms, and revealed the crucial roles of compatible solutes in the flocculation process.

Construction of aldehyde-based, ester-based hyper-cross-linked polar resin and its selective adsorption mechanism for phenol in coal chemical wastewater

Efficient and precise recovery of phenol from coal chemical wastewater (CCW) poses a significant challenge, prompting the development of a novel aldehyde-based, ester-based hyper-cross-linked polar resin (DES–COOC–CHO) in this study. Two distinct functional group modification methods were employed to enhance the screening effect of the resin. SEM, FT-IR, NMR, XPS, and BET characterizations confirmed the successful construction of the hyper-cross-linked polar resin, incorporation aldehyde and ester groups, exhibiting a special surface area of 627.2 m2/g and a microporous specific surface area percentage of 29.94%. DES–COOC–CHO adhered to the pseudo-second-order kinetic model and Langmuir model (maximum adsorption capacity of 118.0 mg/g). Its adsorption of phenol was spontaneous chemisorption, monolayer adsorption. Notably, even after undergoing 20 adsorption–desorption cycles, the resin maintained a stable adsorption capacity, showcasing excellent recoverability. In the presence of phenols sharing similar properties, DES–COOC–CHO exhibited superior selectivity for phenol. In real CCW, it achieved a remarkable 90% selective removal rate of phenol. The primary selective mechanism relied on the hydrogen bonding effect facilitated by aldehyde and ester groups, coupled with microporous sieving of appropriate size. In comparison with other adsorbent materials, DES–COOC–CHO exhibited superior adsorption properties, coupled with a cost-effective preparation process, presenting significant potential for practical applications.

Novel surface structure of LaFeO3/nitrogen-deficient g-C3N4 nanocomposites to improve visible-light photocatalytic performance toward phenol removal.

Herein, novel surface structure LaFeO3/nitrogen-deficient g-C3N4 nanocomposites (LaFeO3/g-C3N4-H) have been successfully synthesized by a two-step process. First, nitrogen-deficient graphitic carbon nitride (g-C3N4-H) was produced by thermally condensing melamine that had been treated with acetic acid as a precursor. After that, LaFeO3 was incorporated into the g-C3N4-H nanosheets. The as-prepared nanostructured materials were characterized by XRD, FT-IR, N2 adsorption-desorption experiments, FESEM, and TEM, demonstrating the formation of interfacial interaction and heterogeneous structure in LaFeO3/g-C3N4-H nanocomposites. Additionally, UV-vis diffuse reflectance spectra (DRS) and photoluminescence spectra (PL) have been used to assess the optical properties of the nanohybrids. The results show that the LaFeO3/g-C3N4-H nanocomposite was successfully produced with a reliable interfacial interface, and produced a good heterojunction relationship between g-C3N4-H and LaFeO3 which may significantly boost the photocatalytic activity as compared to prinstine g-C3N4 and LaFeO3. Phenol degradation under visible light irradiation was used to test the photocatalytic activity of LaFeO3/g-C3N4-H, and the results showed that 10%-LaFeO3/g-C3N4-H had significant photocatalytic activity and remarkable adsorption efficiency, with an overall removal rate of phenol up to 88% after 180min of visible light irradiation. This study may present a novel method for developing highly efficient artificial photocatalytic systems.

Sea Urchin-like NiCo2O4 Catalyst Activated Peroxymonosulfate for Degradation of Phenol: Performance and Mechanism.

How to efficiently activate peroxymonosulfate (PMS) in a complex water matrix to degrade organic pollutants still needs greater efforts, and cobalt-based bimetallic nanomaterials are desirable catalysts. In this paper, sea urchin-like NiCo2O4 nanomaterials were successfully prepared and comprehensively characterized for their structural, morphological and chemical properties via techniques, such as X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), among others. The sea urchin-like NiCo2O4 nanomaterials exhibited remarkable catalytic performance in activating PMS to degrade phenol. Within the NiCo2O4/PMS system, the removal rate of phenol (50 mg L-1, 250 mL) reached 100% after 45 min, with a reaction rate constant k of 0.091 min-1, which was 1.4-times higher than that of the monometallic compound Co3O4/PMS system. The outstanding catalytic activity of sea urchin-like NiCo2O4 primarily arises from the synergistic effect between Ni and Co ions. Additionally, a comprehensive analysis of key parameters influencing the catalytic activity of the sea urchin-like NiCo2O4/PMS system, including reaction temperature, initial pH of solution, initial concentration, catalyst and PMS dosages and coexisting anions (HCO3-, Cl-, NO3- and humic acid), was conducted. Cycling experiments show that the material has good chemical stability. Electron paramagnetic resonance (EPR) and quenching experiments verified that both radical activation (SO4•-, •OH, O2•-) and nonradical activation (1O2) are present in the NiCo2O4/PMS system. Finally, the possible degradation pathways in the NiCo2O4/PMS system were proposed based on gas chromatography-mass spectrometry (GC-MS). Favorably, sea urchin-like NiCo2O4-activated PMS is a promising technology for environmental treatment and the remediation of phenol-induced water pollution problems.