Feed Phenol Concentration Research Articles

Fabrication of PEBA/HZIF-8 Pervaporation Membranes for High Efficiency Phenol Recovery.

Phenol and its chemical derivatives serve as essential chemical materials are indispensable for the synthesis of many kinds of polymers. However, they are highly toxic, carcinogenic, difficult to be degraded biologically, and often found in aqueous effluents. Recovery of hazardous phenol from wastewater remains a daunting challenge. Herein, we prepared a hybrid membrane containing polyether block amide (PEBA) matrix and HZIF-8 fillers. To improve the compatibility between ZIF-8 and PEBA, ZIF-8 was modified by using polystyrene (PS) as a template to prepare porous HZIF-8. ZIF-8, composed of zinc nodes linked by the imidazole ring skeleton, is a kind of inorganic material with high hydrothermal stability, ordered pores, and hydrophobic microporous surfaces, which has a wide range of applications in membrane separation. The separation performance of the PEBA/HZIF-8 based membranes for phenol/water is improved due to the presence of PS on the surface of HZIF-8 and the imidazole ring skeleton in ZIF-8, which enhance the π–π interaction between HZIF-8 and phenol molecules. The effects of HZIF-8 content, feed phenol concentration, and feed temperature on the pervaporation performance of PEBA/HZIF-8 membranes were further investigated. The results showed that the pervaporation performance of the PEBA/HZIF-8-10 membrane was promising with a separation factor of 80.89 and permeate flux of 247.70 g/m2·h under the feed phenol concentration of 0.2 wt % at 80 °C. In addition, the PEBA/HZIF-8-10 membrane presented excellent stability, which has great prospect for practical application in phenol recovery from waste water.

S-ZIF-8/PEBA/ZIF-8 pervaporation membrane with in situ growing of ZIF-8 active layer on the surface owing outstanding phenol enrichment performance

Background Phenol and its chemical derivatives, as an essential chemical material, are indispensable for the synthesis of many kinds of polymers. However, they are highly toxic, carcinogenic, and often found in aqueous effluents. Pervaporation (PV) has been widely used to recover organic compounds from wastewater, because it can allow the permeable components in aqueous solution to pass through the membrane preferentially without any regeneration operation and additives.Methods Herein, a gradient PV membrane (S-ZIF-8/PEBA/ZIF-8) was constructed by embedded ZIF-8 into PEBA matrix, and then ZIF-8 active layer was in situ grown on the surface of PEBA/ZIF-8 membrane for phenol enrichment.Significant findings the prepared S-ZIF-8/PEBA/ZIF-8 membrane exhibits outstanding performance of both adsorption selectivity and diffusion selectivity for phenol molecules, which is attributed to the imidazole ring skeleton of ZIF-8 can interact with phenol molecules to form π-π stacking. Moreover, S-ZIF-8/PEBA/ZIF-8 membrane presents excellent separation performance with separation factor and flux of 109.3 and 215.85 g/m2·h, respectively, with feed phenol concentration of 0.8 wt% at 70 oC. In addition, S-ZIF-8/PEBA/ZIF-8 membrane also demonstrates excellent long-term stability means to enrich phenol, which has great prospect for practical application in phenol recover from waste water.

Phenol removal by tailor-made polyamide-fly ash composite membrane: Modeling and optimization

A novel composite membrane was synthesized using crosslinked polyamide and fly ash ceramic substrate for phenol removal. Glutaraldehyde was used as crosslinker. Characterization shows that synthesized membrane possesses good permeability (0.184 l.m-2.h-1.kPa-1), MWCO (1.7 kDa), average pore size (1.08 nm) and good chemical stability. RSM was adopted for phenol removal studies. Box-Behnken-Design using quadratic model was chosen for three operating parameters (feed phenol concentration, pH and applied pressure) against two responses (phenol removal, flux). ANOVA shows that model is statistically valid with high coefficient of determination (R2) value for flux (0.9897) and phenol removal (0.9302). The optimum conditions are obtained as pH 2, 46 mg.l-1 (feed phenol concentration) and 483 kPa (applied pressure) with 92.3% phenol removal and 9.2 l.m-2.h-1 flux. Data validation with deviation of 4% confirms the suitability of model. Obtained results reveal that prepared composite membrane can efficiently separate phenol from aqueous solution.

Effect of process conditions on the aerobic biodegradation of phenol and paracetamol by open mixed microbial cultures

In the context of xenobiotics’ removal in biological wastewater treatment processes, this study investigated the biodegradation of phenol and paracetamol as sole carbon sources by open mixed cultures. Biodegradation of these chemicals was investigated in batch and SBR (Sequencing Batch Reactor) lab-scale experiments. In batch experiments, phenol was biodegraded by unacclimated microorganisms at concentrations 0.2-0.5 g/l. The acclimation time increased with increasing phenol concentration and no biodegradation was observed with an initial concentration of 1 g/l. However, 1 g/l of phenol was biodegraded after previous exposure of the microorganisms to lower concentrations of phenol or to yeast extract and peptone. Batch degradation of paracetamol (0.5 g/l) only occurred after previous exposure of the microorganisms to yeast extract and peptone. SBR experiments were run with 1.0 g/L feed concentration of phenol or paracetamol in a range of SRT (solids residence time, 1–45 d for phenol and 1–145 d for paracetamol). Both substrates were removed as sole carbon sources and COD removal generally increased as the SRT increased, and was higher than 90% for phenol and 80% for paracetamol. A higher fraction of the removed substrate was assimilated into microorganisms for paracetamol than for phenol with growth yields 0.51 and 0.20 g/g COD, respectively. This study shows how process conditions (acclimation, substrate concentration, medium composition, SRT) affect the removal of phenol and paracetamol and gives guidance on their selection for the optimum biodegradation performance.

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.

Performance and Isotherm Studies in Phenol Adsorption From Wastewater Using Low Cost Biomass Derived From Coconut Shells

With the growth of urbanization and industrialization, water bodies are getting polluted. Among various pollutants, phenol-based pollutants are common water pollutions which originate from wastewater discharged from processing manufacturing industries like petrochemical refineries, ceramic plants, textile processing, leather processing, synthetic rubbers, etc. These pollutants are toxic and have long-term ill effects on both humans and aquatic animals. Adsorption is well proven technique which is widely used for removal of pollutions from aqueous environments. But this process, is hindered due to the cost of adsorbents especially for large scale continuous processes. In this regard, adsorbents derived from waste biomass can be a great asset to reduce the cost of wastewater treatment. To meet this objective, coconut shells are chosen as biomass which is abundantly available from south east Asia. This biomass is converted into activated carbon and hence used to remove phenol from wastewater. Batch adsorption experiments were performed with different initial concentration, carbon dosage, pH and contact time. At a lower concentration of 50 mg/L of initial feed (phenol) concentration resulted in around 90% phenol removal and henceforth optimum results in phenol removal obtained in only 64%. Experimental results are in good agreement with Langmuir adsorption isotherm model and have shown a better fitting to the experimental data. These studies confirm that the coconut shell-based activated carbon could be used to effectively adsorb phenol from aqueous solutions.

Recycling of phenol from aqueous solutions by pervaporation with ZSM-5/PDMS/PVDF hollow fiber composite membrane

Zeolite (ZSM-5)/polydimethylsiloxane (PDMS)/polyvinylidene fluoride (PVDF) hollow fiber composite membrane was prepared by dynamic negative pressure. The influence of ZSM-5 silanization, coating time and concentration of ZSM-5 on the resulting pervaporation (PV) performance of composite membranes was investigated. The contact angle (CA) was used to measure surface hydrophobic property and it was found that the water contact angle of the membrane was increased significantly from 99° to 132° when the concentration of ZSM-5 increased from 0% to 50%. The morphology of the membrane was characterized by scanning electron microscope (SEM) and those SEM images illustrated that the thickness of the separating layer has obvious differences at varying coating times. Furthermore, the membranes were investigated in PV process to recycle phenol from aqueous solutions as feed mixtures. The impact of phenol concentration in feed, temperature and pressure of penetration side on the PV performance of membrane was studied systematically. When the ZSM-5 concentration was 40% and the coating time was 60min, separation factor and phenol permeability were 4.56 and 5.78g/(m2h), respectively. ZSM-5/PDMS/PVDF membrane significantly improved the recovery efficiency of phenols.

Modelling of fluidised-bed reactor by differential evolution optimization for phenol removal using coconut shells based activated carbon

Abstract Phenol is one of the major pollutant released to water resources from manufacturing industries engaged in textile processing, petrochemical production, oil refining, etc. These phenolic compounds are water soluble and being highly toxic has adverse effects on aquatic life and environment. Removal of phenols from wastewaters has become mandatory due to stringent environmental regulations. Adsorption technique found to be effective process compared to other pollutant removal techniques, whereas its applications is limited due to high cost of adsorbents. In this research study, in a fluidised-bed reactor a low cost and easily available agricultural waste of activated carbon from coconut shells, were utilized as adsorbent to study its viability and efficiency for removal of phenol. The operating parameters such as superficial liquid velocity, contact times, feed phenol concentrations and carbon bed heights that influence the performance and characteristics of a fluidised-bed reactor were analyzed systematically. The efficacy of the reactor was evaluated for phenol removal with kinetic and equilibrium studies. The experimental adsorption data were examined by the various isotherm models and the corresponding adsorption rate values were interpreted with linear and non-linear kinetic models. A novel inverse modelling technique based on differential evolution optimization was implemented to estimate the kinetic parameters and non-linear model depicting the relation between the phenol removal efficiency as a function of operating parameters. It was observed from the experimental studies that almost 96% phenol removal can be achieved with lower activated carbon loadings as well as shorter residence time. These experimental results also revealed that coconut shell based activated carbon is a viable cheaper adsorbent for phenols removal from effluent wastewater.

Evaluation of an activated carbon packed bed for the adsorption of phenols from petroleum refinery wastewater.

The performance of an adsorption column packed with granular activated carbon was evaluated for the removal of phenols from refinery wastewater. The effects of phenol feed concentration (80-182mg/l), feed flow rate (5-20ml/min), and activated carbon packing mass (5-15g) on the breakthrough characteristics of the adsorption system were determined. The continuous adsorption process was simulated using batch data and the parameters for a new empirical model were determined. Different dynamic models such as Adams-Bohart, Wolborsko, Thomas, and Yoon-Nelson models were also fitted to the experimental data for the sake of comparison. The empirical, Yoon-Nelson and Thomas models showed a high degree of fitting at different operation conditions, with the empirical model giving the best fit based on the Akaike information criterion (AIC). At an initial phenol concentration of 175mg/l, packing mass of 10g, a flow rate of 10ml/min and a temperature of 25°C, the SSE of the new empirical and Thomas models were identical (248.35) and very close to that of the Yoon-Nelson model (259.49). The values were significantly lower than that of the Adams-Bohart model, which was determined to be 19,358.48. The superiority of the new empirical model and the Thomas model was also confirmed from the values of the R 2 and AIC, which were 0.99 and 38.3, respectively, compared to 0.92 and 86.2 for Adams-Bohart model.

ZIF-8 incorporated polyether block amide membrane for phenol permselective pervaporation with high efficiency

Abstract In recent years, zeolitic imidazolate framework-8 (ZIF-8) has received tremendous attention due to its hydrophobic inner channels and good compatibility with the polymer as an inorganic filler for preparation of the mixed matrix membrane (MMM). In this study, ZIF-8 particles were synthesized and incorporated into Ploy (ether block amide) matrix (PEBA-2533) to fabricate a MMM for the enhancement of phenol permselective pervaporation. The structure and morphology of ZIF-8 particle and the obtained MMMs were characterized by XRD, SEM, FTIR, contact angle and BET. It is found that the hydrophobicity of the membrane was enhanced by the incorporation of hydrophobic ZIF-8, and the obtained MMM withstand the extreme operation conditions of pervaporation. The effects of particle loading amount, feed concentration and temperature on the separation performance of ZIF-8 incorporated MMMs were investigated in details. Compared with the pure PEBA-2533 membrane, the permeate flux of ZIF-8 incorporated PEBA-2533 MMM with a 10 wt% loading amount was significantly increased from 846 g m−2 h−1 to 1310 g m−2 h−1, while the separation factor increased from 39 to 53 at 70 °C with 8000 ppm feed phenol concentration. The enhancement of the pervaporation performance could be mainly attributed to the preferential highly permeable regions of the bimodal membrane structure for phenol molecules, which was consisted of ZIF-8 particles. Finally, both of the excellent overall membrane pervaporation performance and the long-term revealed that such a ZIF-8 incorporated MMM has a great potential in separation and recovery of phenol from its aqueous solution for a practical process.

Modeling of Non-catalytic Supercritical Water Oxidation of Phenol

Abstract The non-catalytic supercritical water oxidation (SCWO) of phenol was modeled using Gopalan-Savage and Thornton-Savage global and network rates. Comparison of experimental data for the phenol conversion with the numerical predictions of this study indicated very close compatibility. Applying the validated model, the phenol conversion and selectivity of various products were studied as a function of effective parameters such as feed phenol concentration, reactor residence time, feed temperature, and feed oxygen concentration. The results of modeling analysis show that an appropriate elevated temperature range (460°C < T <500°C) and long residence time (≈90 s) reduce the concentration of hazardous products (i.e., dimers, dibenzofuran, dibenzo-p-dioxin) and maximize the selectivity of environmental benign products such as water and carbon dioxide. Also, high oxygen concentration (≈0.01 mol/L) increase water and carbon dioxide yield. Moreover, high feed phenol concentrations cause a shortcoming for the SCWO system in terms of phenol conversion and selectivity of desirable environmental products. As a consequence, the feed phenol concentration of ≤2 × 10−3 mol/L is recommended as the appropriate condition.

Solventless extraction/stripping of phenol using trioctylphosphine oxide impregnated hollow fiber membranes – Experimental & modeling analysis

Abstract Trioctylphosphine oxide (TOPO) was impregnated in polypropylene hollow fiber membranes by soaking the membranes first with TOPO containing dichloromethane, and subsequent evaporation of dichloromethane from the membranes. The resulting extractant impregnated hollow fiber membranes (EIHFM) recorded a 60% increase in weight from 0.48 g to 0.77 g. Further evidence of TOPO impregnation was obtained by visualizing TOPO deposition within the membrane walls through scanning electron microscopy. Extraction of 200–2700 mg/L phenol by the EIHFMs was characterized by high uptake rate and capacity, and equilibrium was attained within 1–3 h of contact. Stripping using 0.2 M sodium hydroxide was effective and EIHFM performance remained stable during 10 repeated cycles of extraction and stripping. The mass transfer kinetics of phenol was examined using pseudo-first-order, pseudo-second-order and intraparticle diffusion models, while the distribution equilibrium was modeled using Langmuir, Freundlich, Temkin and Redlich–Peterson isotherms. A kinetics model was also developed based on steady state resistance-in-series approach. The overall mass transfer coefficient was determined and diffusion through the boundary layer was found to be the rate limiting step. The effects of feed phenol concentrations and flow rates on extraction performance of the EIHFMs were simulated, and excellent correlation was obtained between the experimental and the simulated results. These results indicate that the TOPO-based EIHFMs can be used for an effective, sustainable and a relatively solventless extraction of phenol.

Biological removal of phenol from saline wastewater using a moving bed biofilm reactor containing acclimated mixed consortia.

In this study, the performance of an aerobic moving bed biofilm reactor (MBBR) was assessed for the removal of phenol as the sole substrate from saline wastewater. The effect of several parameters namely inlet phenol concentration (200–1200 mg/L), hydraulic retention time (8–24 h), inlet salt content (10–70 g/L), phenol shock loading, hydraulic shock loading and salt shock loading on the performance of the 10 L MBBR inoculated with a mixed culture of active biomass gradually acclimated to phenol and salt were evaluated in terms of phenol and chemical oxygen demand (COD) removal efficiencies. The results indicated that phenol and COD removal efficiencies are affected by HRT, phenol and salt concentration in the bioreactor saline feed. The MBBR could remove up to 99% of phenol and COD from the feed saline wastewater at inlet phenol concentrations up to 800 mg/L, HRT of 18 h and inlet salt contents up to 40 g/L. The reactor could also resist strong shock loads. Furthermore, measuring biological quantitative parameters indicated that the biofilm plays a main role in phenol removal. Overall, the results of this investigation revealed that the developed MBBR system with high concentration of the active mixed biomass can play a prominent role in order to treat saline wastewaters containing phenol in industrial applications as a very efficient and flexible technology.

Oxygen Mass Transfer in Bubble Column Bioreactor

In the present study volumetric oxygen mass transfer coefficient kLa has been determined for biodegradation of phenol in a bubble column bioreactor. Experimental studies have been carried out at different i) feed concentrations of phenol, ii) air flow rates and iii) feed flow rates. Dynamic method has been used to determine the oxygen mass transfer coefficient. The mass transfer coefficient for oxygen obtained is in the range of 0.00513 – 0.01793 s-1. kLa was found to increase with increase in air flow rates and decrease with increase in feed concentration of phenol. The values obtained in this work are compared with the values available in literature. A mathematical correlation is derived for kLa in terms of dimensionless numbers.

Chemical modification of Amberlite XAD-4 by carbonyl groups for phenol adsorption from wastewater

Two carbonyl groups modified XAD-4 resins (XAD-4-I and XAD-4-II) were synthesized by chemically modifying Amberlite XAD-4 with carbon tetrachloride and benzoyl chloride according to the Friedel–Crafts reaction. After the chemical modification, the Brunauer–Emmet–Teller (BET) surface area and pore volume of the resins increased about 50% while their median pore size remained constant. More importantly, the modified resins adsorbed about 20% more phenol from aqueous solutions than the original XAD-4 at 298, 308 and 318K, respectively; and the modified resins could be used directly in water without pre-wetting. The Freundlich and Sips models fitted the isotherm data better than the Langmuir model. Analysis of isosteric adsorption enthalpy indicated that XAD-4 has a more heterogeneous surface than the modified resins. Adsorption kinetics data suggested that the three resins could reach equilibrium within 1h, and the pseudo-first-order and pseudo-second-order rate models could describe the kinetic data effectively. At a phenol feed concentration of 574.0mg/L, the dynamic adsorption capacities of XAD-4, XAD-4-I and XAD-4-II were measured to be 80.6, 94.8 and 93.6mg/g, respectively. Desorption experiments showed that the used resins could be regenerated completely by a 50% (v/v) ethanol aqueous solution.

Catalytic Wet Oxidation in Three-Phase Moving-Bed Reactors: Modeling Framework and Simulations for On-Stream Replacement of a Deactivating Catalyst

Phenol wet oxidation over deactivating catalysts in three-phase moving-bed reactors was simulated by formulating and solving a two-scale, nonisothermal, non-steady-state model to highlight the strength of on-stream catalyst replacement, in comparison to catalyst-batch fixed-bed reactors. Simulation results indicate that three-phase moving-bed reactors offer a promising alternative to fixed-bed reactors. The autonomy of fixed-bed reactors is limited due to severe reduction of catalyst activity, while in moving-bed reactor configurations, the decline of pollutant conversion is reduced with increased solid velocity, to compensate for the decrease in catalyst activity loss. The fixed-bed reactor operates in non-steady-state mode, because of the continuous decline of catalyst activity while moving-bed reactors evolve to steady-state operation after a transient period. Decreasing the reactor feed phenol concentration and increasing liquid residence time in the reactor and feed temperature are the best ways to oppose rapid deactivation of catalyst in moving-bed reactors.

Integrated direct contact membrane distillation for olive mill wastewater treatment

Direct contact membrane distillation (DCMD) process was applied for olive mill wastewater (OMW) treatment and its concentration using a commercial flat-sheet polytetrafluoroethylene membrane (TF200, Gelman) with 0.2μm mean pore size. The effects of the mean temperature and temperature difference on the DCMD permeate flux were studied. Two pre-treatment processes, coagulation/flocculation and microfiltration (MF), were considered and the effects of each one on the DCMD performance were investigated. MF was found to be the optimum pre-treatment to be integrated to DCMD for OMW. When the permeate temperature was kept constant at 20°C, the DCMD permeate flux increased with the increase of the feed temperature. However, the permeate flux decreased with the feed phenol concentration of OMW. The concentration factor of each phenolic compound varied from 1.56 to 2.93. The main phenolic compound in the tested OMW samples was found to be the hydroxytyrosol, which was concentrated more than two times from 4.01g/L to 8.16g/L after 40h of OMW processing by DCMD. The membrane fouling phenomenon was also studied. Results showed that the integrated MF/DCMD can be an effective process for the treatment and concentration of OMW obtaining clean water and a phenolic-rich concentrate.

Performance of anaerobic–anoxic–aerobic batch fed moving-bed reactor at varying phenol feed concentrations and hydraulic retention time

A simulated wastewater containing phenol (1,000–2,500 mg/L), thiocyanate (SCN−) of 800 mg/L, COD (4,200–8,150 mg/L), and ammonia–nitrogen (NH4 +–N) of 500 mg/L was treated in a sequential anaerobic (B1)–anoxic (B2)–aerobic (B3) batch fed moving-bed reactor (MBR) system. Total hydraulic retention time (HRT) was varied from 5 to 10 days with B1 2.5 to 5 days; B2 and B3: 1.25–2.5 days each. In B1, 25–63 % of phenol and 23–53 % of COD removals were achieved and feed phenol above 1,500 mg/L, inhibited COD and phenol removals in B1. In B2, more than 90 % phenol removal was achieved along with COD removal and denitrification. In B2, with increase in phenol loading, though phenol and COD removal rates increased, SCN− removal rate decreased above phenol loading of 0.28 g/L day. In B3, NH4 +–N removal efficiency decreased above loading of 0.24 g NH4 +–N/L day. The overall efficiency of the fed batch MBR system was independent of feed phenol concentration up to 2,500 mg/L at constant total HRT of 6 days. NH4 +–N removal efficiency deteriorated significantly, when total HRT of fed batch MBR was less than 6 days. Modified Stover–Kincannon model showed the best fit for removal of substrates in three reactors and Haldane’s inhibition model predicted NH4 +–N removal in B3.

Behaviour of RO98pHt polyamide membrane in reverse osmosis and low reverse osmosis conditions for phenol removal

Phenolic compounds and their derivatives are very common pollutants in wastewaters. Among the methods described for their removal, pressure‐driven membrane processes are considered as a reliable alternative. Our research group has previously studied phenol removal in reverse osmosis (RO) conditions and obtained very low rejection percentages. Subsequently, when low reverse osmosis (LRO) conditions were studied, the organic rejection percentages improved. To further our knowledge in this respect, the main objective of this work was to study the behaviour of the polyamide thin‐film composite membrane RO98pHt used for phenol removal in RO and LRO conditions. The influence of different operating pressures, phenol feed concentrations and pH on permeate flux and phenol rejection was studied. Low reverse osmosis conditions led to higher phenol rejection percentages in all the assayed conditions, suggesting that other factors related to the molecular characteristics of the organic molecules, such as solubility, acidity and hydrogen bonding capacity, play an important role in the rejection percentage attained. As expected, permeate flux was greater in RO conditions.

Influence of organic fouling and operating conditions on nanofiltration membranes to reduce phenol concentration in natural waters

Phenol is a product widely used in manufacturing and as a disinfectant for industrial and medical applications. The treatment of aqueous effluents polluted with phenol and phenolic species has deserved much attention in the last years due to the toxicity and low biodegradability of those organic compounds. Nanofiltration (NF) has a great potential to remove these contaminants. The main objective of this work is to study the influence on the rejection of phenol by a NF90 2540 NF membrane of various operating conditions: pressure (0.3, 0.4 and 0.5 × 106 N/m2); phenol feed concentration (from 0.025 kg/m3 up to 0.150 kg/m3) and pH (from 5.9 to 11.5). The influence of organic fouling is also investigated. Results showed that when different phenol concentrations were compared at the same pressure, permeate fluxes decreased as phenol concentrations increased (from 20% for the highest phenol feed concentration tested to 10% for the lowest); when phenol concentration increased, phenol was probably adsorbed onto the membrane, which led to lower rejection values (from 78 to 59% rejection). Changes in the pH of the solution altered the phenol dissociation equilibrium and membrane rejection characteristics. The reduction in phenol rejection by organic fouling (maximum of 35%) was a consequence of the materials deposited onto the membrane, which led to the formation of a cake layer.