Microbial fuel cells (MFCs) pertain to a kind of modern technology for the direct conversion of chemical energy in organic matter from wastewaters into electricity during the oxidation of organic substrates. A system of continuous MFC was constructed for the treatment of real petroleum refinery wastewater (PRW). The treatment of real PRW, operational performance of the MFC system, biodegradation of furfural, and energy output were investigated in this study. The MFC was inoculated by mixed anaerobic bacteria, with Bacillus sp. as the dominant type, and continuously operated for 30 days. The biodegradation of furfural and phenol, which are the most prevalent toxicants in refinery wastewater, was investigated. The MFC system reached maximum energy outputs of 552.25 mW/m3 and 235 mV. In the anodic chamber, the maximum removal of furfural and phenol was higher than 99%, with biodegradation of organic content reaching up to 95%. This study demonstrated the viability of a continuous-flow MFC system as a green technology for the treatment of furfural-rich real refinery effluents while generating electricity.
In this research, Polymer Inclusion Membrane (PIM) was created using copoly-eugenol ethylene glycol dimethacrylate (co-EEGDMA) 10% as a carrier, dibenzyl ether (DBE) as a plasticizer, and polyvinyl chloride (PVC) as the base polymer. Following that, the membrane was used in phenol transport experiments under a variety of circumstances, including pH of the phenol in the source phase, NaOH concentrations in the receiving phase, and transport times. The ability and stability of the membrane were also evaluated under several influencing parameters such as plasticizer concentration, salt concentration, and PIM membrane age (lifetime). Phenol concentration was analyzed using UV-Vis spectrophotometer, and PIM membrane was characterized before and after use using Fourier-transform infrared spectroscopy (FT-IR). According to the testing findings, phenol had an ideal pH of 5.5 in the source phase and a concentration of 34.07% in the receiving phase. Additionally, it was discovered that the ideal NaOH content in the receiving phase was 0.5 M with a phenol concentration of 58.24%. The experiments with varied transport times demonstrated that the optimum time was 48 hours with the phenol concentration of 90.82% in the receiving phase. The results of UV-Vis spectrophotometry analysis demonstrated that phenol transportation of 91.54% was achieved with the use of 0.3132 g plasticizer. Under ideal circumstances of pH 5.5 of phenol solution in the source phase, 0.5 M NaOH concentration, and phenol transport time of 48 hours, a membrane prepared from PVC as a base polymer, 10% co-EEGDMA as a carrier, and DBE as a plasticizer can be used to transport phenol. The membrane’s stability was only 24 days when no NaNO3 salt was added, but it grew to 108 days when 0.01 M NaNO3 salt was added.
Several environmental companies consider phenols compounds to be very dangerous pollutants because they are highly toxic and non-biodegradable, notably their high toxicity in water. For this reason, several processes have been studied by researchers to understand the mechanisms of elimination of phenolic compounds. Adsorption remains the best technique due to its characteristics, in fact, it is non-destructive and simple to use as well as have more other advantages, such as practicality and efficiency and low cost, Therefore, these methods need to be widely developed on an industrial scale to remove phenol derivatives and achieve wastewater quality in accordance with standards. On the other hand, the development of these adsorption methods is highly dependent on new research on materials from abundant natural resources, namely apatites or biomaterials.
The effect of a static magnetic field (MF) of 7 mT with phenol (P) or p-chlorophenol (p-chP) concentrations of 100 mg∙dm-3 on the proliferation of Saccharomyces cerevisiae yeast was investigated. The abundance of the microorganism was determined under static culture conditions on a YPG medium with or without the addition of P or p-chP and exposed or unexposed to the MF over 48 h of the experiment. A static MF of 7 mT was shown to have a stimulating effect on S. cerevisiae cell proliferation after 24 h. It was proved that P and p-chP were used as an additional carbon source by yeasts. The greatest stimulation of the growth of the studied microorganisms was observed under the simultaneous effect of an MF and in presence of either P or p-chP. It was generally about 2 times higher at the time of the study than in the control. Statistical analysis of the results was carried out using, among other things, analysis of variance (ANOVA). A statistically significant difference in the growth of the tested microorganisms was observed. The study results indicate the possibility of applying an MF of 7 mT to enhance the process of phenol and p-chlorophenol removal from industrial wastewater.
The production wastewater contains phenol from the Non-Destructive Testing (NDT) unit because it uses solvents; meanwhile, the manganese originates from the metal material washing process. On the basis of laboratory test results, the wastewater originating from the NDT unit of Y Industry, resulted in a phenol level of 2.33 mg/L, exceeding the quality standard of 0.5 mg/L and manganese level of 14.13 mg/L that exceeded the quality standard of 2 mg/L, based on the Regulation of the Minister of the Environment Number 5 of 2014 concerning Wastewater Quality Standards. This research used the pretest-posttest experimental research design without control. The sample in this study was wastewater from the NDT unit of the Y Industry. The average phenol level after passing through the adsorbent media at a thickness of 40 cm, 60 cm, and 80 cm resulted in 0.99 mg/L with 63% reduction, 0.60 mg/L with 77% reduction, and 0,28 mg/L with 89% reduction, respectively. The average manganese level after passing through the adsorbent media at a thickness of 40 cm, 60 cm, and 80 cm resulted in 0.10 mg/L with 61% reduction, 0.06 mg/L with 76% reduction, and 0,05 mg/L with 80% reduction, respectively. The most effective thickness variation in reducing the phenol and manganese levels of NDT wastewater is 80 cm thickness.
Emulsion Liquid Membrane (ELM) has garnered much attention, for its simple operation and high selectivity for the target solute. For an ELM process to be successful, emulsion stability and formulation of liquid membrane are the two main criteria. This study investigated an ELM formulation to identify a suitable green surfactant over the ordinary ones to reduce the utilization of chemicals. The stability of water-in-oil-in-water (w/o/w) was assessed in the following ways, by altering the concentrations of the egg yolk and NaOH, homogenizer speed, and emulsification time. To ascertain the favorable conditions for phenol extraction, several experiments were performed, adopting the batch process, which included many parameters, like the influence exerted by the pH of the external feed, concentration of surfactant, concentration of the internal phase, time of emulsification, homogenization speed and mixing time. Lower breakage and greater extraction efficiency (0.83% and 82.06%, respectively) were attained at 3.5 pH of the external feed, 4% (v/v) of the surfactant, 0.1 M of NaOH, 7 min of emulsification time, 5800 rpm of homogenizer speed and 3 minutes of mixing time. From the results of this study, egg yolk emerged as a good green surfactant. Thus, the ELM process holds promise as an effective technology for stripping phenol from aqueous solutions.
An organobentonite modified with an amphoteric surfactant, tallow dihydroxyethyl betaine (TDHEB), was used as an adsorbent to simultaneously remove Cu(II) and phenol from wastewater. The characteristic of the organobentonite (named TDHEB-bentonite) was analyzed by X-ray diffraction, Fourier-transform infrared spectra and nitrogen adsorption-desorption isotherm. Batch tests were conducted to evaluate the adsorption capacities of TDHEB-bentonite for the two contaminants. Experiment results demonstrated that the adsorption of both contaminants is highly pH-dependent under acidic conditions. TDHEB-bentonite had about 2.0 and 5.0 times higher adsorption capacity toward Cu(II) and phenol, respectively, relative to the corresponding raw Na-bentonite. Adsorption isotherm data showed that the adsorption processes of both contaminants were well described by Freundlich model. Kinetic experiment demonstrated that both contaminants adsorption processes correlated well with pseudo-second-order model. Cu(II) had a negative impact on phenol adsorption, but not vice versa. Cu(II) was removed mainly through chelating with the organic groups (-CH2CH2OH and -COO-) of TDHEB. Otherwise, partition into the organic phase derived from the adsorbed surfactant was the primarily mechanism for phenol removal. Overall, TDHEB-bentonite was a promising adsorbent for removing Cu(II) and phenol simultaneously from wastewater.
Wprowadzenie do hodowli szczepu St. maltophilia KB2 nanocząstek tlenku niklu nie zahamowało procesu biodegradacji fenolu, a reakcja populacji bakterii była uzależniona od stężenia nanocząstek i użytego surfaktantu. Opracowano metodykę przygotowania stabilnej dyspersji badanych nanocząstek oraz oceniono wpływ wybranych surfaktantów na wzrost komórek szczepu St. maltophilia KB2.
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The introduction of nickel oxide nanoparticles into the St. maltophilia KB2 cultures did not inhibit the phenol biodegradation process, and the reactions of the bacterial population were depended on the nanoparticles concentrations and the surfactant used. The methodology for the preparation of the tested nanoparticles stable dispersion was developed and the influence of selected surfactants on the growth of St. maltophilia KB2 cells was assessed.
Punica granatum L. study is interesting for the functional properties associated to its Phenolic compounds and high volumes of production of this fruit in Jordan. The pomegranate type "pale arils" from Abu Ziyad valley were evaluated during different stages between 20 to 140 days after full bloom, with techniques of chelation, colorimetry and spectrophotometry. The results show that the increasing of sphericity (0.79 to 0.91), size diameter (65.58 to 90.41 mm), juice yield (46.03 to 55.67%), arils mass (31.70 to 61.23%), TSS total soluble solids (11.01 to 16.80), pH (2.7 to 3.6) and anthocyanins (7.43 to 12.41 Cyannidine 3 glucoside/100 g) were associated with the decreasing of thickness of the rind (4.9 to 2.77 mm), TTA Titrable total acidity (3.5 to 1.1%), TPC Total phenolics (389.61 to 251.52 mg Gallic acid/100 g), flavonoids (0.73 to 0.40 mg Catechine/g), tannins (8940.11 to 3324.79 ppm), AA Antioxidant Activity (63.41 to 48.84%) and Ascorbic acid content (28.91 to 9.48 mg/100 g); presenting significant differences p≥0,5. The paleness of rind and arils is positively related to the anthocyanin content expressed by "a" and "C" color coordinates. The actual investigation demonstrates that high values TSS-pH, low content of tannins and TTA could be successfully indicators of maturity stages rather than the concentration of anthocyanins.
Phenol is one of the main pollutants that have a serious impact on the environment and can even be very critical to human health. The biodegradation of phenol can be considered an increasingly important pollution control process. In this study, the degradation of phenol by Pseudomonas fredriksbergsis was investigated for the first time under different growth conditions. Six different initial concentrations of phenol were used as the primary substrate. Culture conditions had an important effect on these cells' ability to biodegrade phenol. The best growth of this organism and its highest biodegradation level of phenol were noticed at pH 7, temperature 28 °C, and periods of 36 and 96 h, respectively. The highest biodegradation rate was perceived at 700 mg/L initial phenol concentration. Approximately 90% of the phenol (700 mg/L) was removed in less than 96 hours of incubation time. It was found that the Haldane model best fitted the relationship between the specific growth rate and the initial phenol concentration, whereas the phenol biodegradation profiles time could be adequately described by the modified Gompertz model. The parameters of the Haldane equation are: 0.062 h−1, 11 ppm, and 121 ppm for Haldane’s maximum specific growth rate, the half-saturation coefficient, and the Haldane’s growth kinetics inhibition coefficient, respectively. The Haldane equation fitted the experimental data by minimizing the sum of squared error (SSR) to 1.36×10-3.
The influence of the alkaline pretreatment of wheat straw with use 0.05M solution of NaOH by 22 hours at 25 °C temperature on the effectiveness of anaerobic digestion under mesophilic condition was the subject of this study. The water soaked straw was used as a control. The results showed that alkaline pretreatment improved the solubility of the straw biomass, increasing dissolved COD and concentration of VFA in the feedstock of 10% and 21%, respectively, compared to the water soaked samples. Consequently, the cumulative biogas yield was enhanced by 21.5%, reaching 412.1 mL gVS-1 for the pretreated biomass. The digestates were similar in terms of TS and VS, but it significantly differed in terms of phenols concentration, the content of which was considerably higher both in the feedstock as also as in digestate containing alkaline pretreated straw. Initial concentration of phenols in the feedstock of 27 mg L-1 did not block the anaerobic digestion, although its inhibiting effect is forecasted. It was concluded that soaking the straw at low loading of NaOH (4% of raw mass (w/w)) under ambient conditions can efficiently improve its usability for biogas production.
Laccase from Trametes Versicolor (E.C. 1.10.3.2) was immobilized on the Fe3O4–graphene hybrid nanocomposite through the covalent attachment method (Lac/Fe3O4/GO). The effect of immobilization conditions on the activity and recovered activities such as contact time, the concentration of glutaraldehyde and enzyme was evaluated. The recovered activity of the immobilized laccase on the Fe3O4–graphene oxide nanocomposite was ca. 86%. Immobilized laccase unlike free laccase retained the activity and exhibited higher resistance to temperature and pH changes and also improved storage and thermal stability. Approximately 70% of relative activity for immobilized laccase was remained after being incubated for 2 h at 55 °C, but free laccase only remained 48%. Immobilized laccase retained 88% of initial activity after storage for 20 days, however, the free laccase only 32%. Finally, Lac/Fe3O4/GO capability was evaluated by the oxidation of phenol, p-chlorophenol, and 2,4-dichlorophenol. Lac/Fe3O4/GO was characterized by SEM, EDX, FT-IR, and AGFM.
Wykonano eksperymenty mające na celu zbadanie wzrostu komórek szczepu KB2 w obecności niklu, przy zastosowaniu fenolu jako źródła węgla i energii. Przeprowadzane badania potwierdziły hamujący wpływ niklu na wzrost badanego szczepu nawet dla niskich stężeń tego metalu.
EN
The influence of nickel on the growth of KB2 strain was tested for different concentrations of metal in the presence of phenol as the sole carbon and energy source. The inhibition effect of nickel on bacterial growth was confirmed even for low concentration of tested metal.
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This study aimed to develop a chromatographic method to quantitatively determine phenol in fish tissues. This method involves solvent extraction of acidified samples, followed by derivatization to phenyl acetate and analysis with gas chromatography coupled with mass spectrometry (GC–MS). Phenol in a representative tissue sample (belly, gill, or renal tubules), which was homogenized with 2 N sulfuric acid, was extracted with ethyl acetate and derivatized to phenyl acetate using acetic anhydride and K2CO3 in water. An n-butyl acetate extract was injected into the GC–MS. The linearity (r2) of the calibration curve was greater than 0.996. The analytical repeatability, which is expressed as the relative standard deviation, was less than 6.14%, and the recovery was greater than 96.3%. The method detection limit and the limit of quantitation were 8.0 μg/kg and 26 μg/kg, respectively. The proposed method is also applicable to the analysis of other biological tissues for phenol and its analogs, such as pentachlorophenol.
Steel production processes generate the coke wastewaters contaminated predominantly by highly toxic phenol. Numbers of physical, chemical and physicochemical methods have been developed for the removal of phenol from coke wastewaters. Biological methods are eco-friendly and present appropriate alternative of conventional processes. Various microorganisms are able to degrade phenolic compounds including sulphate-reducing bacteria (SRB). In this work, we study the adaptation of SRB isolated from natural source to phenol and consequently the application of the adapted bacterial cultures for the biodegradation of phenol from model solutions. Two types of bacterial culture were used (monoculture containing SRB genera Desulfovibrio and mixed bacterial consortium containing SRB genera Desulfovibrio). In experiments the modified Postgate’s medium C was used - sodium lactate as the original energy and carbon source was replaced by phenol with concentration 10 mg/dm3 for adaptation and 50 mg/dm3 for biodegradation. The mixed bacterial consortium has been shown as more capable to be adapted and grow on phenol and it has the better potential for phenol biodegradation as the bacterial monoculture of SRB genera Desulfovibrio.
The release of phenol-containing effluents above the phenol permissible limit has triggered a lot of concern over the world due to their toxic nature. The adsorptive potential of gypsum on the removal of phenol was investigated. The effect of gypsum loading (0.5–3 g), contact time (2.5–20 min) and solution temperature (298 to 318 K) on the removal of phenol by gypsum was studied at neutral pH. The thermodynamics of the adsorption process was also studied. The kinetic data were fitted into the pseudo-second-order, Elovich, and intraparticle diffusion models. The removal efficiency of phenol increased along with the mass of gypsum, contact time and temperature. The results of the thermodynamics study indicate that the adsorption process is spontaneous and endothermic in nature. The change in free energy (ΔG0) was found to increase with temperature. The values of the estimated ΔG0 suggest that the phenol adsorption on gypsum is a physical adsorption process. Additionally, the kinetic data fitted best into the pseudo-second-order than the other kinetic models. This study proved that phenol can be used effectively for the reduction of phenol concentrations in water and wastewater.
This paper is related to study the using sea lettuce (Ulva lactuca) as a low-cost adsorbent for removing the phenol compounds from aqueous solutions by adsorption under different operating conditions in a batch unit. The SEM and FTIR tests were performed to determine the morphological characteristics and the functional groups existing on the adsorbent material, respectively, while the surface area was identified by means of two techniques which were blue color method and BET method. The results of the adsorption experiments showed that the efficiency of the removal process is inversely proportional with initial concentration of phenol, pH and temperature; while the efficiency was directly proportional to adsorbent amount, agitation speed and treatment time. The results showed that the percentage of removal of phenol from processed water solutions ranged from 25.446% to 90.125%. The Langmuir and Freundlich isotherm models were chosen to estimate the amounts of phenol adsorption by the sea lettuce powder. The kinetic study shows that the adsorption was obeyed pseudo second order also the thermodynamic parameters were calculated.
Zbadano adsorpcję fenolu i jonów miedzi(II) z modelowych roztworów wodnych na sferycznym węglu aktywnym utlenianym nadtlenodisiarczanem(VI) diamonu w różnych warunkach. Do oceny stopnia modyfikacji węgla wykorzystano analizę elementarną oraz izotermy adsorpcji pary wodnej i benzenu. Wykazano, że adsorpcję fenolu i jonów Cu(II) z roztworów wodnych można dobrze opisać modelami izoterm Freundlicha i Langmuira. Stwierdzono, że adsorpcja fenolu zmniejszała się wraz ze wzrostem stopnia utlenienia węgla i spadkiem jego powierzchni właściwej. Adsorpcja jonów Cu(II) zwiększała się wraz ze wzrostem stopnia utlenienia powierzchni węgla aktywnego, wykazując dużą rolę kwasowych grup tlenowych w adsorpcji jonów metalu na drodze wymiany jonowej. Wykazano również, że nadtlenodisiarczan(VI) diamonu okazał się bardzo skutecznym utleniaczem, gdyż nawet utlenianie węgla w najbardziej łagodnych warunkach (stężenie 0,1 mol/dm3, czas 30 min) dało znaczące zwiększenie ilości związanego tlenu (ok. 3,4-krotne) oraz znaczące zwiększenie ilości adsorbowanych jonów miedzi(II), przy stosunkowo niedużym zmniejszeniu ilości adsorbowanego fenolu.
EN
Adsorption of phenol and copper(II) ions from model aqueous solutions on spherical activated carbon oxidized with ammonium persulfate under various conditions was investigated. Elemental analysis and adsorption isotherms of water and benzene vapors were employed to assess the extent of modifications of the activated carbon surface. It was demonstrated that adsorption of phenol and Cu(II) ions from aqueous solutions could be well described by the Freundlich and Langmuir isotherm models. Adsorption of phenol decreased with the increasing degree of carbon oxidation as well as its decreasing specific surface area. Adsorption of the Cu(II) ions increased with the increasing degree of carbon surface oxidation indicating an important role of acidic groups in adsorption of metal ions by ion-exchange mechanism. Furthermore, ammonium persulfate was demonstrated to be an efficient oxidizing agent as carbon oxidation under even the mildest conditions (0.1 mol/dm3, 30 min) led to a significant increase in the oxygen bound (about 3-4 times) as well as the Cu(II) ions adsorbed. The amount of the adsorbed phenol decreased only slightly.
Surfactant and phenol were removed using AMBERLITE IRA 900 Cl ion-exchange resin, which is a strong alkali. In the process, the tests were carried out under non-flow conditions, the effect of contact time and ionite dose on the surfactant and phenol exchange was determined. The tests under the through-flow conditions were realized in three consecutive cycles, preceded by regeneration and rinsing. The obtained results served for determination of ion-exchange capabilities of the studied ionite. The usable ion-exchange capabilities of the resin obtained after the second and third ionite operation cycle were lower by about 10% (surfactant) and 14.29-17.86% (phenol) than those after the first cycle. It shows that the process of sorption occurred simultaneously with the ion-exchange process.
Phenol and its derivatives (chlorophenol, nitrophenol, methylphenol, cresol etc.) belong to highly toxic contaminants, and their occurrence in industrial and municipal sewage as well as in groundwater carries a high threat to the environment and human health. Elimination of such contaminants is one of the major challenges in solving the global environmental problems. Implementation of pro-ecological methods of water treatment is associated with the use of natural, cheap and unprocessed materials, with the possibility of their repeated use. The article presents the results of the studies on the use of powdery adsorbents for the removal of phenol from aqueous solutions. The following natural minerals were used: attapulgite – Abso'net Superior Special (ASS) and alganite – Abso'net Multisorb (AM). Tests were performed under non-flowing conditions, in series, depending on the type and dose of adsorbents. Tests were conducted on a model solution of phenol with the initial concentration of C0 = 20 mg /dm3, at the temp. of 20° C. Alganite mineral (AM) proved to be effective in adsorption of phenol. Maximum adsorption capacity P = 0.21 g/g, was obtained for a dose 10 mg/dm3. Almost complete removal of phenol (99.9%) was obtained for a dose of 500 mg/dm3. For natural attapulgite – Abso'net Superior Special (ASS) the maximum adsorption capacity (at a dose 5 mg/dm3) amounted to P = 0.15 g/g. The efficiency of phenol removal at the level 99% was obtained at a dose of 1000 mg/dm3).
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