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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.

A new type of multifunctional metal-organic frameworks (MOFs) was synthesized by encapsulating gold nanoparticles (AuNPs) into the Cu-hemin MOFs, and first applied to an electrochemical sensor to detect catechol (CT) with the aid of electrochemically reduced graphene oxide (ERGO) for signal amplification. First, ERGO was electrochemically deposited on a bare glass carbon electrode (GCE), followed by casting Cu-hemin MOFs on an ERGO-modified electrode, and then growing AuNPs in situ on Cu-hemin MOFs/ERGO/GCE by electrochemical deposition. Cyclic voltammetry (CV), scanning electron microscopy (SEM) and current–time ($I$–$t)$ were utilized to characterize the electrochemical performance and surface characteristics of the as-prepared sensor. The results demonstrated that Cu-hemin MOFs have not only been a matrix to avoid the aggregation of AuNPs but also an ideal loading platform for the adsorption of CT due to its large surface area and porosity. In addition, the ERGO also has the advantage of fast electron transfer, which can make synergy with AuNPs@Cu-hemin MOFs nanocomposites to amplify the electrical signal. The AuNPs/Cu-hemin MOFs/ERGO/GCE exhibited an excellent electrocatalytic activity with increased electrochemical signals towards the oxidation of CT. Under the optimum experimental conditions, the sensor shows a wide linear relationship over the range of $2.0\times 10^{-6}$M to $1.692\times 10^{-3}$M with a detection limit of $2.0\times 10^{-7}$M. Moreover, the sensor presented the good reproducibility and the excellent anti-interference performance. This work would broaden the application of MOFs material in constructing more novel electrochemical sensing platform.

In the current work, activated carbon monoliths have been prepared by application of different phenolic hydrocarbons namely catechol and resorcinol as carbon precursors. For synthesis of carbon monolith, the precursors have been mixed with Genapol PF-10 as template and then polymerized in the presence of lysine as catalyst. Then the polymerized monolith carbonized in inert atmosphere at 700°C and activated by water steam at 550°C. It was found that resorcinol polymerization is easier than catechol and occurred at 90°C while for polymerization of catechol elevated temperature of 120°C at hydrothermal condition is necessary. The prepared activated carbon samples have been characterized by various analysis methods including scanning electron microscopy (SEM), surface area measurement, and transmission electron microscopy (TEM). The adsorptions of three different aromatic hydrocarbons by the prepared activated carbon samples have also been investigated by high performance liquid chromatography (HPLC) and UV–Vis spectroscopy. It was found that carbon monolith prepared by catechol as carbon precursor has higher adsorpability and strength in comparison with the other sample. The higher performance of carbon monolith prepared by catechol can be associated with its higher active sites in comparison with resorcinol.

The ability of the fungus Fusarium moniliforme to degrade phenol, catechol, 2,4-dichlorophenol and their mixtures was investigated in the present study. The biodegradation studies were performed in a liquid medium with the phenolic compounds as a sole carbon and energy source. It was found that temperature of 25 oC was optimal for 100% degradation of phenol, 2,4-dichlorophenol and catechol in concentration of 1.0 g/L. In case of mixtures of phenols in concentration of 1.0 g/L phenol + catechol was degraded 100 %, phenol + 2,4-dichlorophenol - 55% and 2,4- dichlorophenol + catechol only 35 %. Our study shows that investigated phenols were metabolized by the β-ketoadipate pathway, through ortho-fission of catechol.

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.