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The treatment of phenol-containing wastewater is a hot topic in the field of environmental chemistry. In this work, the hydroxyl grafted graphite phase carbon nitride (g-C₃${\text{N}}_4)$ was prepared by alkaline hydrothermal (AH) treatment, and its degradation of phenol under visible light was investigated. XRD, UV-Vis, FT-IR, XPS, N₂ adsorption, PL, ESR, TPD and EIS were used to characterize the as-prepared catalysts. The results showed that the hydroxyl group grafting does not influence the crystal structure, optical property and specific surface area of catalyst. Compared with the hydroxyl group modified g-C₃N₄ prepared by H₂O₂ method, the alkali hydrothermal treatment can graft more hydroxyl groups onto the g-C₃N₄ surface, leading to the higher electron–hole separation efficiency. The as-prepared catalyst using this method had more surface negative charges and stronger adsorption capacity for the reaction substrate phenol. The g-C₃N₄ prepared by this alkali hydrothermal treatment displayed the phenol degradation rate constant of 0.22h${}^{-1}$, which is 3.72 and 2.06 times higher than that of neat and H₂O₂ treated g-C₃N₄, as well as excellent catalytic stability and structural stability. The possible reaction mechanism was proposed.

Liquid phase catalytic selective hydroxylation of phenol to catechol and hydroquinone was carried out in the presence of metalloporphyrins using hydrogen peroxide as oxidant and water as solvent. Five kinds of metal tetra(p-chlorophenyl)porphrin (T(p-Cl)PPMCl, M = Fe, Co, Mn, Cu, Zn) were studied. It was found that T(p-Cl)PPFeCl had high catalytic activity and diphenol selectivity for the hydroxylation of phenol to catechol and hydroquinone. The influence of various reaction parameters, namely, reaction temperature, solvent, ratio of substrate and oxidant, substrate concentration, the amount of catalyst, reaction time and pH value were investigated systematically. When water was used as solvent (10 mL), the optimum conditions were following: pH = 7, the concentration of phenol was 0.3 g/mL, the molar ratio of phenol and H₂O₂ was 1/2, the molar ratio of catalyst and phenol was 7/100000, the reaction temperature was 65°C and the reaction time was 1.5 h. Under above optimum conditions, the phenol conversion was up to 55.1%, and the selectivity of diphenol was almost up to 99.9%, the molar turnover numbers of the catalyst was about 7500. A possible mechanism was also proposed.

Sixteen strains of filamentous fungi were isolated from soil samples collected from Livingston Island, Antarctica. The isolates’ taxonomic identifications were performed based on morpho-dimensional parameters following the most suitable identification keys for the different genera. The affiliation of the investigated strains was established to the particular genera. The obtained fungal isolates were members mostly to the genera Penicillium, Aspergillus and Cladosporium. All strains were studied for their ability to adapt to aromatics containing media. Most of the investigated strains demonstrated good tolerance to the presence of 0.5 g/l phenol in the culture medium. More than that the investigations showed that strains were able to grow in a culture medium containing phenol in concentrations varying form 0.1 to 0.7 g/l as a single source of carbon and energy. The experiments carried out with hydroxyl-, methyl- and nitro- phenol derivatives revealed the capability of some of the strains to grow and utilize various of these aromatic compounds. The strains Aspergillus sp. AL1, Aspergillus sp. AL8, Aspergillus AL9, Aspergillus sp. AL15, Penicillium sp. AL5 and Penicillium AL11 were able to grow and utilize as a sole carbon sources 0.3 g/l of each examined aromatic compound. There were not found strains able to utilize any of the tested nitrophenols. The representatives of Cladosporium as well as strain Lecanicillium sp. AL12 did not show any capability to degrade phenol derivatives.

The Fe₂O₃ nanoparticles have been prepared by the co-precipitation and followed by calcination process. The as-prepared Fe₂O₃ nanoparticles were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray analysis (EDS), and X-ray diffraction (XRD). Catalytic wet air oxidation of phenol with molecular oxygen using the Fe₂O₃ nanoparticles catalyst at different temperatures has been studied. The results showed that the catalytic activity of the Fe₂O₃ nanoparticles for phenol degradation can be increased with increasing the temperature, and the degradation of phenol catalyzed by the Fe₂O₃ nanoparticles fits the first-order kinetics.

Voltammetric sensors based on phthalocyanines have been used to detect a variety of compounds. In this paper, the state of the art of sensors prepared using classical techniques will be revised. Then, new strategies to improve the performance of the sensors will be described using as example sensors chemically modified with lutetium bisphthalocyanine (LuPc${}_2)$ dedicated to the detection of phenols of interest in the food industry. Classical LuPc₂ carbon paste electrodes can detect phenols such as catechol, caffeic acid or pyrogallol with limits of detection in the range of 10${}^{-4}$–10${}^{-5}$ M. The performance can be improved by using nanostructured Langmuir–Blodgett (LB) or Layer by Layer (LbL) films. The enhanced surface to volume ratio produce an increase in the sensitivity of the sensors. Limits of detection of 10${}^{-5}$–10${}^{-7}$ M are attained, which are one order of magnitude lower than those obtained using conventional carbon paste electrodes. Moreover, these techniques can be used to co-immobilize two electrocatalytic materials in the same device. The limits of detection obtained in LB sensors combining LuPc₂/AuNPs or LuPc₂/CNT are further improved. Finally, the LB technique has been used to prepare biosensors where a phenol oxydase (such as tyrosinase or lacasse) is immobilized in a biomimetic environment that preserves the enzymatic activity. Moreover, LuPc₂ can be co-immobilized with the enzyme in a lipidic film formed by arachidic acid (AA). LuPc₂ can act as an electron mediator facilitating the electron transfer. These biomimetic sensors formed by LuPc₂/AA/enzyme show Limits of detection of 10${}^{-8}$ M and an enhanced selectivity.

A phenol biosensor based on the skillful immobilization of tyrosinase on zinc oxide (ZnO) nanorods was proposed. The ZnO nanorods fabricated by a simple vapor-phase transport method possess a high aspect ratio, good electron communication, chemical purity, smooth and positive charged surface and are ready for immobilization of biochemicals with low isoelectric point (IEP). Electrochemical measurement and Scanning Electron Microscopic (SEM) analysis showed that the enzyme of tyrosinase with IEP 4.5 can be adsorbed on the surface of ZnO nanorods and kept its bioactivity of the oxidation of phenol to a large extent. This led us to develop phenol biosensor with good stability and reproducibility. The proposed method creates a new way to develop biosensors using nanostructured materials with high IEP.

An efficient N-doped reduced graphene oxide (N-RGO)/Ag₃PO₄ nanocomposite with enhanced photocatalytic activity has been prepared through a facile solution-based approach. Since N-RGO could offer more sites for the anchoring of Ag₃PO₄ nanoparticles, and effectively promote the charge carriers separation and transfer due to its high electrical conductivity, the photocatalytic activity of N-RGO/Ag₃PO₄ nanocomposite is much higher than bare Ag₃PO₄ and N-RGO in the degradation of phenol pollutant under simulated solar light irradiation. The mechanism for the photocatalytic process was also investigated. The excellent photocatalytic performance makes the N-RGO/Ag₃PO₄ nanocomposite a promising photocatalyst for organic pollutant treatment.

Pt/CeO₂–ZrO₂–SnO₂/ZrO₂/SBA-16 catalysts were synthesized for the complete oxidation of phenol in liquid-phase under moderate condition. The loading of ZrO₂ onto SBA-16 effectively enhanced the catalytic activity of Pt/CeO₂–ZrO₂–SnO₂/ZrO₂/SBA-16 due to the increase of the oxygen release and storage abilities of the CeO₂–ZrO₂–SnO₂ promoter. Among the prepared catalysts with various ZrO₂ loading amounts (0–36wt.%), the Pt(7wt.%)/Ce${}_{0.68}$Zr${}_{0.17}$Sn${}_{0.15}$O₂ (16wt.%)/ZrO₂(24wt.%)/SBA-16 exhibited the highest activity, and the complete phenol removal was achieved after the reaction at 80^∘C for 8h under the atmospheric pressure.

Novel Pt/ZrSn${}_{1-x}$Sr${}_x$O${}_{4-\delta }$/SBA-16 (SBA-16: Santa Barbara Amorphous No. 16) catalysts were developed for liquid-phase phenol oxidation. As the promoter to accelerate phenol oxidation on Pt, a ZrSnO₄ solid with an $\alpha$-PbO₂-type structure was chosen because its interstitial open spaces are expected to facilitate phenol adsorption. Additionally, the redox reaction of Sn${}^{4+/2+}$ provides oxygen release and storage abilities, and the introduction of low-valent Sr${}^{2+}$ ions into the ZrSnO₄ lattice improves oxide ion migration via the generation of oxygen vacancies in the lattice structure. Among the samples prepared, the 9.0 wt.% Pt/8.1 wt.% Zr${}_{1.11}$Sn${}_{0.85}$Sr${}_{0.04}$O${}_{4-}$${}_{\delta }$/SBA-16 catalyst showed the highest activity, resulting in a phenol removal percentage of up to 99.7% after 6 h of reaction at 80${}^{\circ }$C under atmospheric pressure.

In this study one hundred and forty seven strains of actinomycetes from urban and industrial wastewater treatment plants with foaming problems were isolated and identified by using phenotypic and genotypic procedures. The chemotaxonomic tests and the analysis of the sequences of gene 16S rRNA showed that the isolated belonged to the genera Corynebacterium, Dietzia, Gordonia, Mycobacterium, Rhodococcus, Tsukamurella and Williamsia. Biodegradation assays were carried out in three different mineral media supplemented with phenol and naphthalene as sole carbone source. The catalysis of the aromatic ring was confirmed by PCR of gene catA, which encodes cathecol 1,2-dioxygenase. The amplified catA genes were sequenced. It is shown with this study that residual wastewater treatement plants can be a good source of microorganisms with many potential applications, such as bioremediation and biodegradation.