Phenol Degradation Research Articles

Thermophilic lignin-based laccase nanozyme with CuNx center for the detection of epinephrine and degradation of phenolic pollutants.

Natural laccases are a family of multi‑copper oxidases that can oxidize multiple phenol substrates and of great importance to contaminant remediation and biosensing. However, the construction of substitutes for the expensive and perishable laccase used in harsh conditions remains a great challenge. Here, we reported a novel strategy for the fabrication of copper-doped lignin-based laccase nanozymes (Cu-AL) through the coordination of aminated lignin and different copper sources. The Cu-AL prepared from CuSO4, possessed highest Cu content and Cu+ proportion, exhibited the best laccase-like activity to various phenols degradation. Strikingly, the thermophilic Cu-AL exhibited superior catalytic activity at 100 °C (3.23 times than that of 60 °C) and durability (> 50 % activity even after 160 days stored in water). Furthermore, a smartphone-based detection platform was successfully developed to achieve the rapid, convenient, and accurate detection of epinephrine concentration. In summary, this work provides a new sustainable and low-cost way to design robust laccase nanozymes from lignocellulose biomass, especially for expanding the applications of enzymatic reaction with high-temperature operation and/or long-term storage in environmental remediation and biosensing.

Nonaqueous Contact-Electro-Chemistry via Triboelectric Charge.

Mechanochemistry revolutionizes traditional reactions through mechanical stimulation, but its reaction efficiency is limited. Recent advancements in utilizing triboelectric charge from liquid-solid contact electrification (CE) have demonstrated significant potential in improving the reaction efficiency. However, its efficacy remains constrained by interfacial electrical double-layer screening in aqueous solutions. This study pioneered chemistry in nonaqueous systems via CE for catalysis and luminescence. Density functional theory simulations and experiments revealed varying electron transfer capabilities and chemoselectivity of CE across different solvents. Phenol degradation via CE in dimethyl sulfoxide (DMSO) exhibited a rate over 40 times faster than that of traditional mechano-driven chemistry. A more intuitive comparison revealed that CE degradation of phenol in DMSO exhibits a 30-fold rate improvement compared to deionized water, where the degradation remains incomplete. Luminol oxidation by radicals generated solely via CE in DMSO eliminates the dependence on traditional catalysts and side reactions, establishing a pure and simple system for investigating the reaction mechanisms. A high and stable luminescence characteristic was maintained for 3 months, enhancing the imaging accuracy and stability exponentially. This study underscores the impact of triboelectric charge on reaction efficiency and chemoselectivity, establishing a new paradigm in nonmetal catalysis, mechanoluminescence, and providing profound insights into reaction kinetics.

Phytomediated synthesis of WO3 nanoparticles using Solanum lycopersicum fruit extract for enhanced photocatalytic activity of 2,4-dichlorophenol

ABSTRACT In the present study, bio-citric acid/tungsten oxide (WO3) (BCAWO) nanoparticles (NPs) were prepared by using Solanum lycopersicum fruit extract as a reducing as well as a capping agent. The photocatalysts were characterized by UV–vis diffuse reflection spectroscopy, powder X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDS), high-resolution transmission electron microscopy, and photoluminescence spectroscopy techniques. Diffraction peaks in the XRD spectrum were identified as the crystal planes of crystalline tungsten oxide. The BCAWO had an average size of 23.14 nm. For W–O bonds, the Fourier transform infrared spectrum displays the vibrational peak at 671.23 cm−1. A prominent absorption band was observed at 268 nm, indicating the 1.2 eV bandgap. Under xenon (Xe) lamp irradiation, the synthesized BCAWO nanoparticles showed notable photocatalytic degradation of 2,4-dichlorophenol (2,4-DCP), with a degradation rate of 96%. With BCAWO concentrations of 2.5 g/L, pH of 4, reaction period of 180 min, and 2,4 DCP concentration of 10 mg/L, the degradation of 2,4-DCP had the highest efficacy, 96%. The degradation of phenols in wastewater may be facilitated by using the green WO3 nanoparticles as a photocatalyst, according to the results.

Cultivation of deep-sea bacteria from the Northwest Pacific Ocean and characterization of Limnobacter profundi sp. nov., a phenol-degrading bacterium

Despite previous culture-independent studies highlighting the prevalence of the order Burkholderiales in deep-sea environments, the cultivation and characterization of deep-sea Burkholderiales have been infrequent. A total of 243 deep-sea bacterial strains were isolated from various depths in the Northwest Pacific Ocean, with 33 isolates (13.6%) from a depth of 4000 m classified into Burkholderiales. Herein, we report the isolation and genome characteristics of strain SAORIC-580T, from a depth of 4000 m in the Northwest Pacific Ocean. The strain showed a close phylogenetic relationship with Limnobacter thiooxidans CS-K2T, sharing 99.9% 16S rRNA gene sequence identity. The complete whole-genome sequence of strain SAORIC-580T comprised 3.3 Mbp with a DNA G+C content of 52.5%. Comparative genomic analysis revealed average nucleotide identities between 79.4–85.7% and digital DNA-DNA hybridization values of 19.9–29.5% when compared to other Limnobacter genomes, indicating that the strain represents a novel species within the genus. Genomic analysis revealed unique adaptations to deep-sea conditions, including genes associated with phenol degradation, stress responses, cold adaptation, heavy metal resistance, signal transduction, and carbohydrate metabolism. The SAORIC-580T genome was found to be more abundant in the deep sea than at the surface in the trenches of the Northwest Pacific Ocean, suggesting adaptations to the deep-sea environment. Phenotypic characterization highlighted distinct differences from other Limnobacter species, including variations in growth conditions, enzyme activities, and phenol degradation capabilities. Chemotaxonomic markers of the strain included ubiquinone-10, major fatty acids such as C16:0, C16:1, and C18:1, and major polar lipids including phosphatidylethanolamine, phosphatidylglycerol, and diphosphatidylglycerol. Based on the polyphasic taxonomic data, it is concluded that strain SAORIC-580T (= KACC 21440T = NBRC 114111T) represents a novel species, for which the name Limnobacter profundi sp. nov. is proposed.

Synthesized CuO-PEI-JE with 3D open-cell structure as an efficient heterogeneous activator of peroxodisulfate for phenol degradation

The core of heterogeneous catalytic systems is to design high-performance heterogeneous catalysts. In the present study, CuO-PEI-JE was synthesized via in situ precipitation of CuO on the 3D structure of PEI-JE prepared by a cross-linking method. It possessed a macro-size and 3D open-cell structure, being easily separated and having super-performance for PDS activation. Compared to PDS alone (0.0017 min-1), the CuO-PEI-JE+PDS+NaHCO3 system increased the kobs (0.3526 min-1) by a factor of 207 with 100% phenol degradation within 20 min and 87% TOC removal at 30 min. It outperformed many other published heterogeneous persulfate systems in phenol degradation. Meanwhile, the developed system displayed a good anti-interference ability in the coexistence of anions or different water matrixes. After five successive cycles, the degradation rate still kept 100%, exhibiting the excellent reusability of CuO-PEI-JE. Furthermore, the preparation of CuO-PEI-JE had the advantages with moderate preparation conditions (60 °C) and readily available raw materials. The activation mechanism was mainly involved in the formation of active PDS and its further decomposition into ·OHads, SO4·-ads, O2·- and 1O2. Surface functional groups and phenol acted as electron donors for active PDS. Phenol was first degraded into hexadienedioic acid, then oxidized to propane diacid and oxalic acid, and finally mineralized into CO2 and H2O. This work provides a new strategy for preparing effective heterogeneous persulfate activators and has high potential for the treatment of phenol-containing wastewater.

Activation of peroxymonosulfate by Fe based metal organic framework for selective degradation of phenol in water

Phenol is a common pollutant in various wastewater, which is required to be removed to a certain standard before the wastewater can be discharged. Persulfate-based advanced oxidation processes (PS-AOPs) are an effective technology for phenol removal, with efficacy contingent upon the activation methods and materials employed. In this study, Fe-based metal-organic frameworks (Fe-MOFs) constructed with carboxylic acid as a ligand were synthesized by a solvothermal method, which can form chelates with ferrous ions. Fe-MOFs showed the activity similar to the homogeneous catalyst thus improving their activation efficiency, and can be used to activate peroxymonosulfate (PMS) for phenol degradation in water. The effects of catalyst dosage, PMS and phenol concentration, temperature, and pH on the degradation efficiency were investigated. Under the optimum reaction conditions, the 96 % of phenol can be rapidly removed in 5 min. SO4·− was determined as the primary radical. Fe species on Fe-MOFs acted as the key active sites. Density functional theory (DFT) analysis suggested enhanced charge redistribution, fostering electron-rich sites that facilitate electron transfer in AOPs, thus boosting phenol degradation. The Fe-MOFs/PMS system enables iron recycling and efficient phenol degradation in water, indicating the potential for phenol-contaminated water treatment.

Dual-Functional Cu-Fe Co-Doped TiO₂ Photocatalyst for Efficient Hydrogen Production and Phenol Degradation

Dual-Functional Cu-Fe Co-Doped TiO₂ Photocatalyst for Efficient Hydrogen Production and Phenol Degradation

Novel visible-light-driven I- doped Bi2O2CO3 nano-sheets fabricated via an ion exchange route for dye and phenol removal

Here, we developed a novel visible-light-driven I- doped Bi2O2CO3 nano-sheet photocatalyst fabricated via a facile ion exchange route at room temperature. This obtained Bi2O2CO3 nano-sheets with I- doping showed several advantages. The specific surface area of I0.875-Bi2O2CO3 was 2.16 times higher than that of Bi2O2CO3, providing more catalytic site for degradation reactions. Moreover, a 3.2 times photocurrent enhancement was observed in I0.875-Bi2O2CO3 comparing with Bi2O2CO3, producing more photogenerated electron-hole pairs for degradation reactions. The synergistic effect between texture property and photoelectric effect boosted the removal of organic pollutants. Under visible light illumination, I0.875-Bi2O2CO3 displayed superior photocatalytic performance for degradation of methyl orange and phenol. Notably, a phenol degradation rate of 88% was achieved over I0.875-Bi2O2CO3 with illuminating for 60 min, which was about 29 times higher than Bi2O2CO3. This finding may provide an opportunity to develop a promising I- doped catalyst for organic pollutants removal.

A Novel Cu/Fe Cathode Prepared by a Facile Redox Pathway for Phenol Degradation Electrocatalytically via the Electro-Fenton assisted Electro-Chlorination Process

A Novel Cu/Fe Cathode Prepared by a Facile Redox Pathway for Phenol Degradation Electrocatalytically via the Electro-Fenton assisted Electro-Chlorination Process

Photocatalytic Degradation of Phenol using Copper-Doped Graphitic Carbon Nitride under Fluorescent and Sunlight Irradiation

Photocatalytic Degradation of Phenol using Copper-Doped Graphitic Carbon Nitride under Fluorescent and Sunlight Irradiation

Regulating the Electronic Structure of Cu Single-Atom Catalysts toward Enhanced Electro-Fenton Degradation of Organic Contaminants via 1O2 and •OH.

Heterogeneous electro-Fenton degradation with 1O2 and •OH generated from O2 reduction is cost-effective for the removal of refractory organic pollutants from wastewater. As 1O2 is more tolerant to background constituents such as salt ions and a high pH value than •OH, tuning the production of 1O2 and •OH is important for efficient electro-Fenton degradation. However, it remains a great challenge to selectively produce 1O2 and improve the species yield. Herein, the electronic structure of atomically dispersed Cu-N4 sites was regulated by doping electron-deficient B into porous hollow carbon microspheres (CuBN-HCMs), which improved *O2 adsorption and significantly enhanced 1O2 selectivity in electro-Fenton degradation. Its 1O2 yield was 2.3 times higher than that of a Cu single-atom catalyst without B doping. Meanwhile, •OH was simultaneously generated as a minor species. The CuBN-HCMs were efficient for the electro-Fenton degradation of phenol, sulfamethoxazole, and bisphenol A with a high mineralization efficiency. Its kinetic constants showed insignificant changes under various anions and a wide pH range of 1-9. More importantly, it was energy-efficient for treating actual coking wastewater with a low energy consumption of 19.0 kWh kgCOD-1. The superior performance of the CuBN-HCMs was contributed from 1O2 and •OH and its high 1O2 selectivity.

Construction and evaluation of electrophotocataltic tubular reactor in phenol degradation

Contamination of the environment is one of the main threats to achieving sustainability. Even though there have been significant legal efforts to regulate parameters for effluent disposal, conventional treatment methods often prove to be ineffective, resulting in the incomplete removal of pollutants. This inefficiency leads to serious environmental issues, such as the toxicity of biomes, which is closely related to the bioaccumulation of harmful substances. In response to this challenge, this study aimed to develop and optimize an electrophotocatalytic reactor for the remediation of a synthetic phenol solution using advanced oxidative processes (AOPs). By applying these processes, we observed that the characteristics of the reaction medium allowed for a maximum pollutant removal yield of 54.73% over a 3-hour operation period in a continuous recirculation regime. Despite the promising results, the study revealed the influence of additional factors that were not considered, which are likely important in further optimizing the reactor's efficiency for real-world applications.

A low-carbon dual-functional evaporator with photothermal and catalytic properties for enhanced VOCs removal during water evaporation

Solar interface distillation technologies are widely used for seawater desalination, wastewater treatment, and clean water production. However, during evaporation, volatile organic compounds (VOCs) in the water often evaporate coincidently with the water vapor, presenting a major pollutant challenge. Combining solar evaporation with advanced oxidation processes (AOP) is a potential solution for simultaneous water purification and VOC degradation. Herein, a dual-functional sponge photothermal evaporator (MBC-SA/MS) was designed to assess the efficacy of this approach. A simple porous sponge embedded with a composite catalyst, comprising MoO3−x, BiOCl, and CNT, was able to demonstrate simultaneous photothermal evaporation and catalytic degradation. MBC-SA/MS exhibited exceptional photothermal conversion efficiency and robust catalytic activity, achieving an evaporation rate of 2.1 kg m−2 h−1 under 1.0 sun intensity. Effective mitigating of phenol emissions was observed through persulfate activation resulting in 90 % phenol degradation. Life cycle assessment (LCA) confirmed this evaporator system had low environmental impact and was sustainable. This research presents a new compelling strategy for tackling VOC pollution and simultaneously enhancing water purification via solar interfacial evaporation.

Enhanced Photocatalytic Degradation Performance by Micropore-Confined Charge Transfer in Hydrogen-Bonded Organic Framework-Like Cocrystals.

Carrier utilization in organic photocatalytic materials is unsatisfactory due to the large exciton binding energy and short exciton diffusion length. Both donor-acceptor (D-A) strategies and porous designs are promising approaches to improve carrier utilization in photocatalysts. However, a more efficient way is to shorten the distance of exciton migration to the catalyst surface by the charge transfer (CT) process. Herein, hydrogen-bonded organic framework-like cocrystal (NDI-Cor HOF-cocrystal) is prepared with novel structures serving as a proof of concept for the approach, using N, N'-bis (5-isophthalate) naphthalimide (NDI-COOH) as the porous framework and acceptor, and Coronene (Cor) as the donor unit. CT and porous engineering are integrated through cocrystal strategy. Under light irradiation, photogenerated excitons transfer and dissociate from the inner surface of the micropores on a hundred-picosecond time scale, where efficient radical transformation and further redox reactions with adsorbed phenol molecules occur. NDI-Cor HOF-cocrystal photocatalytic degradation of phenol is 15 times higher than that of original HOFs, and achieves near 90% deep mineralization of phenol. Significantly, this work has designed novel HOF-cocrystal and also provides new modification strategies for high performance organic photocatalysts.

Ultrasound and its coupled oak blocks treatment based on absorbed energy density for comprehensive insight and scale-up consideration of phenolic and astringency profiles in red wines

Ultrasound and ultrasound-coupled oak blocks techniques on the phenolic and astringency profiles of Petit Verdot wines were discussed in this study. The relationship between techniques at varying absorbed energy density (AED) gradients and astringency was revealed, elucidating potential molecular mechanisms regarding compound interactions. Ultrasound was found to promote phenolics degradation and condensed tannins maturation, while oak blocks improved ellagitannins release into wines, facilitating polycondensation reactions to form larger complexes. Phenolics binding to salivary proteins decreased at low AED values (0–33.07 J/mL), enhanced at high AED values (66.14–165.34 J/mL), and reduced salivary proteins' precipitation ability. Treated samples significantly altered astringency's global terminology and sensory attributes across oral regions, with oak blocks enriching the astringency hierarchy. Multivariate analysis identified an optimal ultrasound AED of 0 to 33.07 J/mL, and an effective PLS-DA model was developed for industrial scale-up considerations, aiming to cost-effectively enhance the organoleptic quality of wines.

Highly efficient photocatalysis-Fenton degradation of antibiotics and phenol over sulfidated FeOCl under natural sunlight illumination

Sulfidated FeOCl is prepared as a heterogeneous photo-Fenton catalyst. And the surface sulfidation of FeOCl can remarkably accelerate the photoinduced charge separation and transfer, while also increase Fe2+/Fe3+ atomic ratio, leading to the boosted photo-Fenton activity in the presence of H2O2. Under irradiation of natural sunlight (light intensity: ∼80 mW·cm−2), over 10 mg sulfidated FeOCl catalyst with using 20 μL 15 % H2O2, 91.2 % of ofloxacin solution (50 mg·L−1) and 97.5 % of sulfisoxazole solution (60 mg·L−1) can be degraded in 80 min, and 99.6 % of phenol solution (625 mg·L−1) is decomposed in 4 h. Under irradiation of a white Light-Emitting Diode (LED) lamp (light intensity: 5 mW·cm−2), 99.8 % of ofloxacin solution is decomposed after treatment for 4 h. Moreover, this photo-Fenton degradation system displays a stable activity in a wide range of pH (1−10), diverse water bodies, and various coexisting ions with concertation from 1 mM to 500 mM. Moreover, sulfidated FeOCl catalyst coated on a frosted glass sheet exhibits excellent stability for degrading ofloxacin even in seven continuous cycles. Particularly, the non-toxicity of the treated ofloxacin, sulfisoxazole, and phenol solution, have been proven by testing their toxic effects on cabbage seed, bacteria, and human embryonic kidney cell, respectively.

Improved Photocatalytic Activity of Dion-Jacobson-Type Tantalate Perovskites Modified with FeCl2.

A rapid and feasible approach was used to develop visible-light-driven-type Dion-Jacobson perovskites by the modification of the RbLaTa2O7 host (RbLTO) with FeCl2 through the molten salt route. X-ray diffraction (XRD) characterization showed that FeCl2-modified layered perovskite (e.g., Fe@RbLTO) preserved its lamellar structure. SEM micrographs confirmed the layered morphology of both RbLTO and Fe@RbLTO perovskite materials. The UV-Vis spectra illustrated a significant red shift of the absorption edge after Fe2+ modification, with the band gap energy reducing from 3.88 to 1.82 eV. H2-TPR measurements emphasized the anchorage of Fe2+ species located on the surface of the layered perovskite as well as in the interlayer space. The synthesized materials were valorized as photocatalysts for the degradation of phenol under both Xe lamp and simulated solar irradiation (SSL) conditions. The photocatalytic reaction follows first-order kinetics. By-product formations during phenol (Ph) degradation were identified and quantified using high-performance liquid chromatography (HPLC). Hydroquinone, 1,2-dihydroxi-benzene, benzoquinone, and pyrogallol were identified as the main Ph degradation intermediates. Pristine RbLaTa2O7 exhibited a phenol conversion value of about 17% using an Xe lamp, while a ≈ 11% conversion was achieved under SSL. A substantial increase in Ph conversion and selectivity was perceived after Fe2+ modification. Fe@RbLTO demonstrated superior photocatalytic performances (43% conversion of phenol under an Xe lamp, and 91% selectivity to aromatic intermediate compounds) at optimized reaction conditions. The stability of the Fe@RbLTO photocatalyst when exposed to an Xe lamp was also assessed. These results suggest that the existence of iron species on the layered perovskite's surface is responsible for the improved redox properties of Fe@RbLTO, resulting in a valuable material for environmental applications.

Electrosynthesis and characterization of nanostructured manganese dioxide thin film on stainless steel electrode for electrochemical degradation of phenol

Electrosynthesis and characterization of nanostructured manganese dioxide thin film on stainless steel electrode for electrochemical degradation of phenol

Regulate catalytic performance by engineering non-regular structure of extradiol dioxygenase: An entrance to bottom strategy

Extradiol dioxygenase Tcu3516 is a home-sourced enzyme demonstrating potent aromatic phenol degradation capacity. To add to the advantageous modifications inside active cavity, this work reported a novel strategy to engineer rarely concerned non-regular structures around the entrance towards the active site at the bottom of cavity. Three structures, Loop region 1 (Loop1: Met173-Arg185), Loop region 2 (Loop2: Ala201-Val212) and C-terminal (C-tail: His290-Lys306) were therefore identified through structural flexibility analysis. Highly rigid prolines within the structures were mutated into smaller alanine, glycine, or serine to improve structural flexibilities; while only P183S on Loop1 showed 3-fold activity enhancement vs the WT when subjected to cleavage of mono-cyclic catechol analogues. The analysis of Root Mean Square Fluctuation showed that P183S presents certain enhancement on Loop1 flexibility without dramatic changes of other domains. Furthermore, the synergetic effects from mutation P183S and cavity-based mutations V186L, V212N and D285A were evaluated by characterizing combinatorial mutants. Temperature dependence and thermostability of the combined mutants showed a more flexible catalytic domain without sacrificing structural integrity and stability. kcat value of P183S/V186L (SL) towards monocyclic catechols significantly surpasses any other combinatorial mutants around Tcu3516 active sites. Moreover, the synergetic effects on conformational plasticity were analyzed by molecular dynamic simulations to shed light into the interplay between structural changes and catalytic performance.

In situ treatment of contaminated soil using persulfate activated by sulfidated zero-valent iron

Soil contamination with hazardous substances like phenol poses significant environmental and health risks. In situ soil mixing can be a promising technological solution to this challenge. A persulfate and sulfidated zero-valent iron (S-ZVIbm) system for remediating contaminated soil was developed and tested to be suited to in situ soil mixing. S-ZVIbm was synthesized using a ball mill process, and the optimal sulfur to iron molar ratio for effectively removing phenol from soil removal without pyrophoric risks was 0.12. Soil slurry experiments were performed, and the best phenol oxidation results (high stoichiometric efficiency and sustained oxidation after mixing) were achieved at a persulfate to S-ZVIbm molar ratio of 2:1 and a persulfate to phenol molar ratio of 8:1. A high organic matter content of the silty clay fraction of the soil strongly suppressed persulfate activation, so suppressed phenol removal and increased persulfate consumption. Electron spin resonance and radical scavenging tests confirmed that hydroxyl and sulfate radicals were present during the degradation of phenol. While sulfate radicals predominantly facilitated degradation in the soil, both sulfate and hydroxyl radicals were crucial in the aqueous phase in the absence of soil organic matter. In situ soil mixing simulation tests indicated that the persulfate and S-ZVIbm doses and the mixing rate and duration strongly affected the efficacy of the system, and the optimal conditions for phenol removal were determined. The results indicated that the persulfate/S-ZVIbm system could be tuned to achieve sustained persulfate activation and to remediate contaminated soil employing in situ soil mixing technique.