Maximum Phenol Removal Research Articles

Photocatalytic treatment of mixed selenocyanate and phenol streams: Process modeling, optimization, and kinetics

AbstractElevated selenium presence in the aquatic bodies because of increased industrial practices and the resulting toxicity concerns have prompted selenium treatment. Although most studies have focused on selenite (SeO32−) and selenate (SeO42−) removal, however selenocyanate (SeCN−) is another Se‐species whose treatment is challenging often because of a complex wastewater matrix and presence of co‐pollutants such as phenol. The present study therefore investigated the efficiency of TiO2 photocatalysis (with EDTA as a hole/h+ scavenger) for the treatment of mixed selenocyanate/phenol wastewater along with response surface methodology (RSM) based process optimization, determination of reaction intermediates, and kinetic modeling. The application of face‐centered central composite design (CCD) RSM modeling yielded Natural Log Transformed Linear model for selenium removal, and non‐transformed two‐factor interaction model for phenol removal. These models were duly validated using statistical tools, and then tested employing additional experiments. The optimal process conditions for maximum selenium and phenol removal were found to be pH 4, 10 ppm selenocyanate, 5 ppm phenol, and 450 ppm EDTA. Findings from the reaction byproducts analysis indicated selenite, selenate, benzenediols, and benzeneseleninic acid as most noted intermediates. A kinetic model that predicts the changes in parent compounds selenocyanate/phenol and dominant reaction intermediates during photocatalysis is also presented.

Using Fe3O4-coated nanofibers based on cellulose acetate/chitosan for adsorption of Cr(VI), Ni(II) and phenol from aqueous solutions

This work aims at investigating Fe3O4-coated nanofibers based on cellulose acetate (CA) and chitosan (CS) for adsorption of Cr(VI), Ni(II), and phenol from aqueous solutions. The synthesized Fe3O4 nanoparticles (NPs), and the modified nanofibrous adsorbents are characterized by using FTIR and FE-SEM analyses. The optimum conditions for independent parameters such as adsorbent dosage, pH, contact time, and initial concentration of the adsorbates on the maximum removal of Cr(VI), Ni(II), and phenol are evaluated using the samples with and without Fe3O4 NPs. On the basis of kinetics and mechanism studies of the adsorption, pseudo second-order equation and Redlich-Peterson isotherm model show the best fitting on the experimental data. The obtained results revealed that the maximum monolayer adsorption capacities of Cr(VI), Ni(II), and phenol using Fe3O4-coated CA/CS nanofibers are 193.2 mgg−1, 143.3 mgg−1, and 163.5 mgg−1, respectively. Also, the prepared adsorbents are reused and their performance is assessed for five adsorption-desorption cycles. Moreover, the adsorption of Cr(VI), Ni(II), and phenol in a ternary system is carried out. Finally, by comparing the adsorption outcomes, it is being found that the electrospun CA/CS hybrid nanofibrous sample coated with Fe3O4 NPs is a promising candidate for wastewater treatment potentially.

Phenol removal from aqueous solution using silica and activated carbon derived from rice husk

Abstract Phenol and its derivatives are organic pollutants with dangerous effects, such as poisoning, carcinogenicity, mutagenicity, and teratogenicity in humans and other organisms. In this study, the removal of phenol from aqueous solution by adsorption on silica and activated carbon of rice husk was investigated. In this regard, the effects of initial concentration of phenol, pH, dosage of the adsorbents, and contact time on the adsorption of phenol were investigated. The results showed that the maximum removal of phenol by rice husk silica (RHS) and rice husk activated carbon (RHAC) in the initial concentration of 1 mgL−1 phenol, 2 gL−1 adsorbent mass, 120 min contact time, and pH 5 (RHS) or pH 6 (RHAC) were obtained up to 91% and 97.88%, respectively. A significant correlation was also detected between increasing contact times and phenol removal for both adsorbents (p < 0.01). The adsorption process for both of the adsorbents was also more compatible with the Langmuir isotherm. The results of this study showed that RHS and RHAC can be considered as natural and inexpensive adsorbents for water treatment.

Adsorptive removal of phenol using banyan root activated carbon

Adsorption is an easy and efficient technique for phenolic wastewater treatment. The present study highlights the preparation, characterization and application of activated carbon obtained from the banyan tree’s aerial root waste for phenol removal studies. The banyan root activated carbon (BRAC) was chemically modified using potassium hydroxide (KOH) as the activation agent. Various characterization studies revealed the highly porous structure of BRAC with a considerable amount of functional groups present on its surface. Surface area analysis showed a specific surface area of 988 m2/g (BET method) and average pore radius of 24 nm (BJH method). Studies on the relationship between adsorption parameters and adsorption performance indicated that the BRAC possessed a maximum phenol removal efficiency of 89.2% for the optimized values of the adsorption parameters. Thermodynamic investigations showed that the adsorption process was spontaneous and exothermic in nature. Further, the phenol adsorption on BRAC conformed to Langmuir model with a theoretical maximum adsorption capacity of 26.95 mg/g. Kinetic analysis revealed that the phenol adsorption on BRAC followed pseudo-second order model. Reusability studies revealed that BRAC can be reused for a maximum of three cycles for continual phenol adsorption from its aqueous streams. Thus, banyan root waste assures to be a potential and economical biomass for production of activated carbon towards the adsorptive treatment of phenol contaminated wastewater streams.

Remediation of bio-refinery wastewater containing organic and inorganic toxic pollutants by adsorption onto chitosan-based magnetic nanosorbent

AbstractThe novelty of the current study deals with the application of magnetic nanosorbent, chitosan-coated magnetic nanoparticles (cMNPs), to be utilized for the management of lignocellulosic bio-refinery wastewater (LBW) containing three heavy metals and 26 phenolic compounds. The magnetic property of the adsorbent, confirmed by elemental and vibrating sample magnetometer analysis (saturation magnetization of 26.96 emu/g), allows easy separation of the particles in the presence of an external magnetic field. At pH 6.0, with optimized adsorbent dosage of 2.0 g/L and 90 min contact time, maximum removal of phenol (46.2%), copper (42.2%), chromium (18.7%) and arsenic (2.44%) was observed. The extent of removal of phenolic compounds was in the order: polysubstituted > di-substituted > mono-substituted > cresol > phenol. Overall, the adsorption capacity (qe) of cMNPs varies among the different contaminants in the following manner: copper (1.03 mg/g), chromium (0.20 mg/g), arsenic (0.04 mg/g) and phenol (0.56 mg/g). Post-adsorption, retrieving the cMNPs using an external magnetic field followed by single-step desorption via acid–base treatment is attractive for implementation in industrial settings. Reusability of the adsorbent was studied by recycling the cMNPs for five consecutive rounds of adsorption followed by desorption, at the end of which, cMNPs retained 20% of their initial adsorption capacity.

Phenol adsorption from wastewater using clarified sludge from basic oxygen furnace

Phenol (C6H5OH) found in wastewater is included in the list of priority pollutant. Amongst various ways, the effective way of phenol removal is the adsorption using various agricultural and industrial wastes. In this study, the clarified sludge produced from basic oxygen furnace in steel plant was taken as the adsorbent. The adsorbent characterizations were performed using SEM, XRD, and BET analysers. The adsorption percentage was studied with the variation of adsorbent dose (5–25 g/L), phenol concentration (10–40 mg/L), pH (3–9), adsorption time (50–300 min) and temperature (25–35 °C). The maximum phenol removal was observed at around 63% at the optimum conditions, i.e., with an adsorbent dose of 20 g/L, phenol concentration of 10 mg/L, pH of 7, adsorption time of 240 min and temperature of 35 °C respectively. The adsorption results were tested using several kinetic, isotherm, and thermodynamic models. The pseudo-second order (r2 = 0.98862) and the D–R isotherm (r2 = 0.99046) were the best supportive kinetic and isotherm models within the investigated experimental conditions. The thermodynamic study suggested for a non-spontaneous, endothermic, and random process. The novelty of this study is that besides elaborated experimental investigations and testing of models, the discussions on safe disposal of the used adsorbent and scale-up design of pilot data are included in this paper. The study established that the clarified sludge was an effective adsorbent for phenol removal from wastewater.

Phenol Removal by Novel Choline Chloride Blended Cellulose Acetate-Fly Ash Composite Membrane

A novel composite membrane (CM) was prepared by coating choline chloride (ChCl) blended cellulose acetate (CA) on fly-ash based ceramic substrate for phenol removal. Different amount (0-1 g) of ChCl was blended with CA to synthesize various CMs. Amount of ChCl in CA increases the contact angle, average pore radius, permeability of CM from 55.15° to 71.55°, 1.6 to 6.83 nm and 0.0057 to 0.0152 L·m−2·h−1·kPa−1, respectively. Phenol rejection increased from 56 to 93 % while increasing ChCl amount in CA. Phenol removal decreased from 94.26-64.23 % and 91.09-78.62 % with increase in applied pressure (69-483 kPa) and feed concentration (50-200 mg·L−1). However, removal rate increased from 80.46-92.47 % with increase in pH 2-12. Among all CMs, CC5 is identified as best CM with maximum phenol removal efficiency (92.7 %) and flux (1.86 L·m−2·h−1) at 207 kPa applied pressure and 100 mg·L−1 of feed phenol concentration. The obtained results reveal that blending of 0.9 % ChCl with CA can significantly enhances the phenol removal efficiency and this could be used as potential CM for treatment of phenol bearing wastewater.

Fe3 O4 @GO on silica sand as an efficient and economical adsorbent; Typical application for removal of phenol and 2,4-dichlorophenol from water samples.

In this research, the layer-by-layer coating of silica sand surface with monolayer of graphene oxide (GO) immobilized on magnetite nanoparticles (Fe3 O4 MNPs) sublayer was investigated as a novel, low-cost, effective, and green nanocomposite material for adsorption of phenol and 2,4-dichloro-phenol (DCP). Several characterization techniques such as FTIR spectroscopy, X-ray diffraction (XRD) analysis, and scanning electron microscopy (SEM) were used to confirm the successful synthesis of Fe3 O4 MNPs@GO on silica. The efficiency of Fe3 O4 MNPs@GO-coated silica (SiO2 ) for the removal of the target phenolic compounds from water samples was evaluated. The maximum removal of phenol (52%) and DCP (73%) was observed using 1.0g adsorbent, initial concentration of 12.5mg/dm3 (for phenol) and 15mg/dm3 (for DCP), sample volume of 10ml (for phenol) and 15ml (for DCP), contact time of 20min (for phenol) and 10min (for DCP), and pH=5. The adsorption isotherm models of Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich as well as kinetic and intraparticle diffusion models were also examined. Eventually, SiO2 /Fe3 O4 MNPs@GO was regenerated five times for removal of examined contaminants and their removal efficiency from thewater inletof awater treatment plant was assessed. PRACTITIONER POINTS: Immobilizing monolayer of GO nanosheets on silica sands surface for the first time has been achieved. GO monolayer anchors on silica sands through Fe3 O4 nanoparticles as sublayer without using very expensive tris(hydroxymethyl) aminomethane agent. Modified silica sands are introduced as a novel and economic pollutants adsorbent, which can be used in filter sands of water treatment industry. The SiO2 /Fe3 O4 MNPs@GO significantly reduces the amount of phenol and 2,4-dichloro-phenol (DCP) as model organic pollutants from water samples.

Bioattenuation of phenol and cyanide involving immobilised spent tea activated carbon with Alcaligenes faecalis JF339228: Critical assessment of the degraded intermediates

AbstractThe current study is designed for the eradication of phenol and cyanide from a simulated binary mixture involving acetic acid modified spent tea activated carbon (STAC‐C), isolated bacterial strain Alcaligenes faecalis JF339228, and immobilized A. faecalis JF339228 onto spent tea biochar by an amalgamated approach of sorption coupled with biodegradation. Characterisation of the biosorbent was ascertained by field emission scanning electron microscopy, thermogravimetric analysis, and Fourier transform infrared spectroscopy. The viability for eco‐benign expulsion of the pernicious pollutants, and the resultant compounds after treatment was examined by fluorescence and UV‐visible spectrophotometry with comprehensive elucidation of the interactions with DNA. Gas chromatography–mass spectrometry (GC‐MS) anatomization was conducted for the evaluation of degraded derivatives post‐treatment. The chemical and structural analysis of the degraded compounds and its impact upon disposal on the basis of degree of toxicity and reactivity were evaluated using TOXTREE software. Batch studies were implemented for the evaluation of process parameters like pH, reaction time, biosorbent or inoculum dosage, initial concentration, and temperature. Mono and binary component isotherm modelling was executed. Immobilised cells and free cells could accomplish better removal efficacy of 94.71% and 92.25% for cyanide, respectively, whereas adsorption using STAC‐C was responsible for maximum removal of phenol up to 86.29%.

Electrochemical performance and microbial community analysis in air cathode microbial fuel cells fuelled with pyroligneous liquor

Microbial fuels cells (MFCs) have been applied for the degradation of pyroligneous liquor (PL) derived from apple tree branches, at different concentrations. The substrate removal, electrochemical properties, and microbial community characteristics were analysed to evaluate the performance of MFCs. Maximum current density (1.94 A/m2), coulombic efficiency (28%), and phenol removal rate (84%) were achieved with MFCs fed with PL at the optimal concentration of 1 g chemical oxygen demand (COD)/L. The polarisation test, cyclic voltammetry, and electrochemical impedance of the electrode redox reaction further explained how the addition of PL could stimulate formation of the electrochemically active biofilm, at the optimal concentration of 1 g COD/L. The microbial community of the anodic biofilm demonstrated that MFCs fed with 1 g COD/L had the highest relative abundance of the typical electrogenic bacteria Geobacter (33%), followed by Sphaerochaeta (6%) and Clostridium (4%). The results revealed that syntrophic interaction of these functional microorganisms contributed significantly to the PL degradation and electrical current generation.

Phenol adsorption on scoria stone as adsorbent - Application of response surface method and artificial neural networks

In this study, adsorption of phenol from aqueous solutions was studied. Scoria stone was modified by different acids (nitric acid, sulfuric acid, acetic acid, phosphoric acid and hydrochloric acid) at various concentrations. The obtained modified scoria was characterized using the Fourier transform infrared spectrograph (FTIR), scanning electron microscopy (SEM) and x-ray fluorescence (XRF). Adsorption equilibrium data were analyzed using Langmuir, Freundlich, Temkin and Dubinin–Radushkevich isotherms, the results indicated the best fit by the Langmuir isotherm (qm = 67.11 mg/g) and maximum removal of phenol was obtained for sulfuric acid modified scoria (96.84%). In addition, the phenol adsorption was modeled using the pseudo-first order and pseudo-second order models, the best fit being observed with the pseudo-second order kinetic. Modelling of the process was carried out using Response Surface Method and Artificial Neural Networks. The resulting models were then further applied to optimize the phenol adsorption, different combinations of parameters leading to the maximization of efficiency being obtained.

Optimization of phenol removal from wastewater by activation of persulfate and ultrasonic waves in the presence of biochar catalyst modified by lanthanum chloride

AbstractIn this paper, the effects of phenol concentration, pH, catalyst dose, persulfate concentration, temperature and contact time on the phenol removal from wastewater by activation of persulfate (S2O8−2) in the presence of biochar modified by lanthanum chloride and ultrasonic waves (US) are optimized. Experimental design and optimization were carried out by response surface methodology. The optimum conditions for the maximum phenol removal were obtained pH of 4, phenol concentration of 86 mg/L, catalyst dose of 43 mg/L, persulfate concentration of 86 mg/L, temperature of 41 °C and contact time of 63 min. The optimum phenol removal from synthetic wastewater was attained 97.68%. Phenol removal by the mentioned system was fitted with the first‐order kinetic model. The combination of the ingredients of ‘S2O8−2/US/Biochar‐LaCl3’ system had a synergistic effect on the phenol removal.

Low-cost iron-doped catalyst for phenol degradation by heterogeneous Fenton

The aim of this work was to study the feasibility of textile sludge as a precursor to prepare catalysts for catalytic wet peroxide oxidation (CWPO) by chemical and thermal treatments. Textile sludge was characterized by physical-chemical and metal composition analyses. The chemical activation was evaluated using iron sulfate and the thermal treatment was carried out at 720 °C in a vacuum pyrolysis reactor. Two catalysts with iron contents of 1.5% and 5.6% were selected. Process parameters influence on CWPO of phenol were evaluated and a maximum removal of phenol and TOC was observed at pH 3 and 60 °C, using 3 g L−1 of the catalyst containing 5.6% of iron and 11.8 mmol L−1 of H2O2. Metal analysis indicated that the textile sludge is suitable to be employed as both iron catalyst and adsorbent. The catalysts characterization indicated a reasonable surface area with a well-developed microporosity and the presence of Hematite structures in the carbonaceous matrix. The degradation process achieved 98.2% of phenol conversion, 68.2% of mineralization and 2.11 mg L−1 of iron leaching in 150 min of reaction. The catalyst presented activity for up to 5 cycles of use, but with loss of efficiency.

Bioremediation of phenol from synthetic and real wastewater using Leptolyngbya sp.: a comparison and assessment of lipid production.

Bioremediation of wastewater is gaining popularity over chemical treatment due to the greener aspect. The volume of literature containing algal biodegradation is small. Especially, removal of toxic materials like phenol from coke-oven wastewater using fast-growing cyanobacteria was not tried. The current study, therefore, targeted at bioremediation of phenol from wastewater using Leptolyngbya sp., a cyanobacterial strain, as a finishing step. Furthermore, the growth of the strain was studied under different conditions, varying phenol concentration 50-150mg/L, pH 5-11, inoculum size 2-10% to assess its ability to produce lipid. The strain was initially grown in BG-11 as a reference medium and later in phenolic solution. The strain was found to sustain 150mg/L concentration of phenol. SEM study had shown the clear difference in the structure of cyanobacterial strain when grown in pure BG-11 medium and phenolic solution. Maximum removal of phenol (98.5 ± 0.14%) was achieved with an initial concentration 100mg/L, 5% inoculum size at pH 11, while the maximum amount of dry biomass (0.38 ± 0.02g/L) was obtained at pH 7, initial phenol concentration of 50mg/L, and 5% inoculum size. Highest lipid yield was achieved at pH 11, initial phenol concentration of 100mg/L, and 5% inoculum size. Coke-oven wastewater collected from secondary clarifier of effluent treatment plant was also treated with the said strain and the removal of different pollutants was observed. The study suggests the utilization of such potential cyanobacterial strain in treating industrial effluent containing phenol.

Bioremediation of steel plant wastewater and enhanced electricity generation in microbial desalination cell.

Microbial desalination cell (MDC) is a propitious technology towards water desalination by utilizing wastewater as an energy source. In this study, a multi-chambered MDC was used to bioremediate steel plant wastewater using the same wastewater as a fuel for anodic bacteria. A pure culture of Pseudomonas putida MTCC 1194 was isolated and inoculated to remove toxic phenol. Three different inoculum conditions, namely P. putida (INC-A), a mixture of P. putida and activated sludge (INC-B), and activated sludge alone (INC-C) were employed in an anodic chamber to mainly compare the electricity generation and phenol degradation in MDCs. The study revealed the maximum phenol removal of 82 ± 2.4%, total dissolved solids (TDS) removal of 68 ± 1.5%, and power generation of 10.2 mW/m2 using INC-B. The synergistic interactions between microorganisms, can enhance the toxic phenol degradation and also electricity generation in MDC for onsite wastewater application.

Cationization of celluloisc fibers in respect of liquid fuel purification

Abstract Fuel upgrading is one of the globally requirements due to struggle the environmental impacts and to protect the humanity. Presence of oxygenated compounds such as phenol in liquid fuel caused serious problems in the fuel combustion and gums formation in the interior engines and consequently blocking the fuel filter. These problems are directly affected on both of the human's life and environment. Herein, functionalized viscose fibers were designed and applied for liquid fuel purification from phenol. Viscose fibers was firstly cationized by interaction with N-2-chloroethyl N,N diethyl ammonium chloride to produce cationized fibers with nitrogen contents of 0.32–0.52%. Sorption of phenol from n-octane by using the cationized fibers was systematically studied. Sorption capacities were significantly affected by the degree of substitution and were linearly increased with nitrogen contents. The maximum sorption capacities were 178.6 and 206.2–282.5 mg/g for untreated and cationized fibers, respectively. Sorption was obeyed to pseudo-second order and signified that cationization process accelerates the phenol removal process. Sorption of phenol onto fibers were well followed Langmuir isotherm profile which reflected the monolayer sorption. Sorption was taken place via weak interactions between phenol molecules and substituted functional groups of fibers achieving physisorption process. However, the maximum capacity was diminished by regeneration process, the maximum removal of phenol was 80% after 4 regenerated cycles. Cationized viscose fibers can be considered as quite good template to purify liquid fuel from phenols, able to apply several times with good economic viability.

Highly Efficient Separation of Phenolic Compounds from Oil Mixtures by Imidazolium-Based Dicationic Ionic Liquids via Forming Deep Eutectic Solvents

The separation of phenolic compounds from oil mixtures is an important step for further refining or applications of the oil mixtures. In this work, three imidazolium-based dicationic ionic liquids (DILs; 1,2-bis[N-(N′-methylimidazolium)]ethane dibromide, DIL1; 1,3-bis[N-(N′-methylimidazolium)]propane dibromide, DIL2; and 1,4-bis[N-(N′-methylimidazolium)]butane dibromide, DIL3) were synthesized and used to separate phenolic compounds from oil mixtures. The effects of time, temperature, DIL:phenol mole ratio, and initial phenol concentration on separation performance were investigated in detail. It was found that the removal efficiency of phenol followed the order DIL1 < DIL2 < DIL3. DIL3 showed the maximum phenol removal efficiency of 96.6% and the minimum ultimate phenol concentration of 3.9 g/dm3. Initial phenol concentration had little influence on the ultimate phenol concentration. Less than 0.4 in DIL:phenol mole ratio was needed to obtain the highest phenol removal efficiency, and the separation proc...

The use of a multilayer perceptron (MLP) for modelling the phenol removal by emulsion liquid membrane

Extraction of phenol from aqueous solution was studied using emulsion liquid membrane (ELM). In this study, due to the extreme complexity and non linearity of ELM process, a multilayer perceptron (MLP) was developed to predict the extraction efficiency of phenol. The effect of operational parameters such as: the ratios of volume ratio of internal phase to organic phase, volume ratio of emulsion to aqueous external phase, the emulsification speed and time, the surfactant concentration, the extractant and sodium hydroxide concentrations were studied to optimize the conditions for maximum removal of phenol. The results showed that a network with 3 hidden neurons was highly accurate in predicting the extraction efficiency (more than 98%). This accuracy was reflected by high correlation coefficient R=0.99 and a root mean square error below 0.5. The result indicated that the MLP model explained in this study is an applied tool to predict the extraction efficiency of phenol by ELM.

Physicochemical analysis and Treatment of Paper Mill Effluents by Chemical Precipitation Method using Different Metal Salt Doses

This present work has been carried out to study the enhanced efficiency of chemical precipitation treatment for paper mill effluents. After physico-chemical analysis, the chemical precipitation was carried out by using metal salt doses of aluminum chloride, ferric chloride and barium sulphate. The effect of pH and metal salt doses on the precipitation of pollutants was studied. The conditions were optimized in accordance with the removal of pollutants. The removal efficiencies were measured in terms of the reduction in color, total suspended solid (TSS), chemical oxygen demand (COD) and phenols. The pollution reduction has been analyzed and compared with industrial effluent discharge standards as per central pollution control board (CPCB). A comparative study of different metal salts doses of paper mill effluents by the chemical precipitation methods indicated that maximum color reduction, phenol and COD removal was 99.60%, 53.89 and 67.28% respectively for aluminum chloride, barium chloride and ferric chloride.

Phenol removal from oil refinery wastewater using anaerobic stabilization pond modeling and process optimization using response surface methodology (RSM)

Oil refinery process releases toxic pollutants into aqueous environment. Phenol and its derivations as the most important pollutants pose severe environmental concern. In this study, the rectangle anaerobic stabilization pond (ASP) consisting of feed tank with workload of 60 Lit (1 × 0.2 × 1) meter of phenol was used. This study evaluated the interactive effect of phenol concentration (200–400 mg/l), temperature (8–24°C) and Hydraulic retention time of (HRT) (2–5 d) on the efficiency of anaerobic stabilization pond for oil refinery wastewater treatment. In this study, experiments were carried out based on central composite design (CCD) and analyzed and modeled by response surface methodology (RSM) aimed at demonstrating the operating variables and also the interactive effect of three independent variables on 7 responses. The maximum removal efficiency of SCOD, TCOD, SBOD and TBOD were 66.26, 68.95, 65.3 and 67.02, respectively, at phenol concentration of 200 mg/L, HRT of 2 d, and temperature of 24°C. Generally, the ratio of N/P varied between 6.69–9.12 and 7.04–12.93, respectively, in influent and effluent of anaerobic stabilization pond. The maximum phenol removal efficiency reached 70.53 and 81.63 at phenol concentration of 200 mg/L, temperature of 24°C with HRT (2 and 5 d), respectively. The phenol removal efficiency was significantly influenced by increasing the temperature compared to decreasing the phenol concentration. The result indicated that the anaerobic stabilization pond was a capable biological treatment process that could achieve the moderate removal of oil refinery wastewater. © 2017 Desalination Publications. All rights reserved.