Removal Of Phenolic Compounds Research Articles

Effect of the pendent groups on biobased polymers, obtained from click chemistry suitable, for the adsorption of organic pollutants from water

AbstractIn this work, four triazole‐based poly(ether‐pyridine)s polymers were synthesized and used as an adsorbent for the removal of phenolic compounds from aqueous solutions. For this purpose, new fluoromonomers containing 1,2,3‐triazole units were prepared by the Cu(I)‐catalyzed 1,3‐dipolar cycloaddition reaction and then used for the elaboration of novel poly(ether‐pyridine‐triazole)s (PEPTs) by direct polycondensation with isosorbide and bisphenol A. Chemical structure of fluorinated pyridinic monomers as well as resulting polymers was confirmed by 1H and 19F NMR spectroscopic methods. The thermal behavior of the obtained PEPTs was characterized using differential scanning calorimetry and thermogravimetric analysis. Results of sorption showed that polymers can be effectively used as a sorbent for the removal of polar organic pollutants. The isosorbide‐based poly(ether‐pyridine‐triazole) which contains hydrophilic hydroxyl groups as pendants chains (P4) exhibited the highest sorption efficiencies (78%–100% after 1 h). In order to explain the results an adsorption mechanism mainly based on π–π interactions and hydrogen bonding with the pendent groups is proposed.

Engineering of two-dimensional monolayers to phenolic compounds removal from wastewater: An experimental and computational insight

Discharge of phenol/chlorophenols into the environment endangers the human health and deteriorates the environment which necessiates the development of novel methods to eliminate phenol/chlorophenols. So, in this study, six novel 2D adsorbents have been investigated for the removal of phenol/chlorophenol from aqueous media through simulation and computational methods including all-atom molecular dynamics (MD), coarse-grained, and density functional theory (DFT). The tunability and availability of these adsorbents make them viable candidates as phenol/chlorophenol adsorbents. Molecular simulation provides a splendid view of the interactions between phenol/chlorophenol and adsorbents, as well as the adsorption mechanism. DFT calculations revealed that the removal mechanism of phenol/chlorophenol using ZIF-8-NH2 is physisorption, so the ZIF-8-NH2 is not poisoned by phenol/chlorophenol and can be reused many times. Finally, the results of MD were reinforced by coarse-grained and DFT simulations attesting that ZIF-8-NH2 can be an excellent industrial choice for phenol/chlorophenol removal. In this regard experimental adsorption of phenol on the surface of ZIF-8-NH2 also showed that the observed adsorption data is in good agreement with Freundlich isotherm. Altogether, experimental and computational results declare that ZIF-8-NH2 can be considered as an adsorbent for removing phenolic polutents from aqueous medium for further evaluations.

Use of Anthracophyllum discolor and Stereum hirsutum as a Suitable Strategy for Delignification and Phenolic Removal of Olive Mill Solid Waste.

This study evaluated the use of the white-rot fungi (WRF) Anthracophyllum discolor and Stereum hirsutum as a biological pretreatment for olive mill solid mill waste (OMSW). The WRF strains proposed were added directly to OMSW. The assays consisted of determining the need to add supplementary nutrients, an exogenous carbon source or use agitation systems, and evaluating WRF growth, enzyme activity, phenolic compound removal and lignin degradation. The highest ligninolytic enzyme activity was found at day 10, reaching 176.7 U/L of manganese-independent peroxidase (MniP) produced by A. discolor, and the highest phenolic removal (more than 80% with both strains) was reached after 24 days of incubation. The confocal laser scanning microscopy analysis (CLSM) confirmed lignin degradation through the drop in lignin relative fluorescence units (RFU) from 3967 for untreated OMSW to 235 and 221 RFU, showing a lignin relative degradation of 94.1% and 94.4% after 24 days of treatment by A. discolor and S. hirsutum, respectively. The results demonstrate for the first time that A. discolor and S. hirsutum were able to degrade lignin and remove phenolic compounds from OMSW using this as the sole substrate without adding other nutrients or using agitation systems. This work indicates that it could be possible to design an in situ pretreatment of the valorization of OMSW, avoiding complex systems or transportation. In this sense, future research under non-sterile conditions is needed to evaluate the competition of WRF with other microorganisms present in the OMSW. The main drawbacks of this work are associated with both the low reaction time and the water addition. However, OMSW is seasonal waste produced in one season per year, being stored for a long time. In terms of water addition, the necessary optimization will be addressed in future research.

Vinasse odyssey: sugarcane vinasse remediation and laccase production by Trametes sp. immobilized in polyurethane foam

Vinasse is a high pollutant liquid residue from bioethanol production. Due to its toxicity, most vinasse is used not disposed of in water bodies but employed for the fertigation of sugarcane crops, potentially leading to soil salinization or heavy metal deposition. The anaerobic digestion of vinasse for energy production is the main alternative to fertigation, but the process cannot eliminate colored compounds such as melanoidins, caramels, or phenolic compounds. The treatment of raw vinasse with white-rot fungi could remove colored and persistent toxic compounds, but is generally considered cost-ineffective. We report the treatment of vinasse by an autochthonous Trametes sp. strain immobilized in polyurethane foam and the concomitant production of high titers of laccase, a high value-added product that could improve the viability of the process. The reuse of the immobilized biomass and the discoloration of raw vinasse, the concentration of phenolic compounds, BOD and COD, and the phytotoxicity of the treated vinasse were measured to assess the viability of the process and the potential use of treated vinasse in fertigation or as a complementary treatment to anaerobic digestion. Under optimal conditions (vinasse 0.25X, 30°C, 21days incubation, 2% glucose added in the implantation stage), immobilized Trametes sp. causes a decrease of 75% in vinasse color and total phenolic compounds, reaching 1082 U L-1 of laccase. The fungi could be used to treat 0.50X vinasse (BOD 44,400mg O2 L-1), causing a 26% decolorization and a 30% removal of phenolic compounds after 21days of treatment with maximum laccase titers of 112 U L-1, while reducing COD and BOD from 103,290 to 42,500mg O2 L-1 (59%) and from 44,440 to 21,230mg O2 L-1 (52%), respectively. The re-utilization of immobilized biomass to treat 0.50X vinasse proved to be successful, leading to the production of 361 U L-1 of laccase with 77% decolorization, 61% degradation of phenolic compounds, and the reduction of COD and BOD by 75% and 80%, respectively. Trametes sp. also reduced vinasse phytotoxicity to Lactuca sativa seedlings. The obtained results show that the aerobic treatment of vinasse by immobilized Trametes sp. is an interesting technology that could be employed as a sole treatment for the bioremediation of vinasse, with the concomitant the production of laccase. Alternatively, the methodology could be used in combination with anaerobic digestion to achieve greater decolorization and reduction of phenolic compounds, melanoidins, and organic load.

Efficient and rapid removal of typical phenolic compounds from water with biobased porous organic polymers

Removing phenolic compounds from water resources is urgent as they have seriously damaged aquatic ecological equilibrium. In this study, divanillin-based porous organic polymers (DPP) and 2,5-furandicarboxaldehyde-based porous organic polymers (FPP) were prepared from sustainable lignocellulose-derivatized monomers using a one-step synthetic method. The characterization highlighted the large Brunauer–Emmett–Teller (BET) surface area (SBET 513.9 and 772.8 m2∙g−1), mainly mesoporous property (3.4 and 6.5 nm) and high nitrogen content (over 25%) of the obtained DPP and FPP, which rendered them high adsorption affinity toward phenolic pollutants. Specifically, DPP and FPP exhibited the highest adsorption capacity for p-nitrophenol (PNP) (254.2 and 339.4 mg∙g−1) calculated by the Langmuir isotherm model. The porous networks of DPP and FPP enabled fast sorption kinetics for PNP with adsorption equilibrium times of only 8 and 4 min, respectively. Thermodynamic investigation revealed adsorption followed spontaneous and exothermic chemisorption processes. The interaction between the PNP and DPP/FPP mainly involved the synergism of hydrogen-bonding interactions, electrostatic force, and π-π stacking interactions. Furthermore, DPP and FPP exhibited outstanding durability and retained over 78.9% and 81.9% removal efficiency for PNP after ten cycles. Therefore, these biobased materials with high adsorption capacity and rapid adsorption rate show promising application in wastewater treatment.

Optimization of preparation conditions of a novel low-cost natural bio-sorbent from olive pomace and column adsorption processes on the removal of phenolic compounds from olive oil mill wastewater.

Olive oil mill wastewater (OMWW) poses an undeniable environmental problem due to its high organic loads and phenolic compound (PC) content. This study determined the optimal conditions for preparing a new bio-sorbent from olive pomace (OP) and the adsorptive treatment of OMWW by this bio-sorbent. The activation reaction was performed with hydrogen peroxide. The results of the combination effect optimization of the three preparation variables, the activation temperature (°C) X1, the activation time (min) X2, and the impregnation ratio X3, are presented by the response surface methodology (RSM). The maximum adsorption capacity was obtained at an activation time of 240 min, a temperature of 80 °C, and a ratio equal to 6.2:1. The bio-sorbent was characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffractometer (XRD). The adsorption process performance of this bio-sorbent was examined in batch (phenol solution) and fixed-bed columns (real effluent of OMWW). An adsorption capacity of 789.28 mg g-1 and 643.92 mg g-1 has been achieved for 4000 mg L-1 concentration of PCs, respectively, for batch and fixed-bed column essays. The adsorption isotherm and kinetics were consistent with the Langmuir and pseudo-second-order models. Therefore, the Thomas model best fits the fixed-bed column experimental data. The bio-sorbent gave a high desorption percentage of PCs, which was above 60% using HCl (0.1M).

Green production of low-molecular-weight xylooligosaccharides from oil palm empty fruit bunch via integrated enzymatic polymerization and membrane separation for purification

For xylooligosaccharides (XOS) production from agricultural residues, highly concentrated xylan liquor (116 g/L) was produced by crushing an oil palm empty fruit bunch (EFB) via continuous hydrothermal treatment and subsequent membrane-based concentration on a pilot scale. The yield of xylan extracted from the raw EFB was 53.7%. To produce XOS with a low degree of polymerization, xylanase-catalyzed hydrolysis was performed and the sum of xylobiose and xylotriose to extracted xylan was 81.6% under lab-scale optimal conditions and 69.3% under pilot-scale conditions. In addition, the crude XOS could be purified through a novel approach involving enzyme-mediated radical polymerization and membrane-based separation, while minimizing XOS loss and waste generation. As a result, 50.2% of the total phenolic compounds in the crude XOS material could be polymerized and precipitated through peroxidase-catalyzed reactions, and an additional 22.6% were removed using the membrane. Furthermore, the amount of activated carbon consumed and the XOS recovery rate after phenolic compound removal via the adsorption method using activated carbon were evaluated and compared with the integrated enzyme-membrane purification results. Consequently, this study provides an ecofriendly biomass refinery process for low-molecular-weight XOS production and purification that produces few toxic substances and little waste.

Production of bio-oil from sugarcane bagasse by fast pyrolysis and removal of phenolic compounds

Production of bio-oil from sugarcane bagasse by fast pyrolysis and removal of phenolic compounds

Evaluation of the Activation Procedure on Oxone Efficiency for Synthetic Olive Mill Wastewater Treatment

Wastewater from the olive oil industry is an environmental problem which is growing in the Mediterranean region. Presence of phenolic compounds and high organic matter load are characteristics of this effluent that make it difficult to treat. In this study, the applicability of sulfate radical based advanced oxidation processes (SRbAOPs), using peroxymonosulfate (PMS) as oxidant, was evaluated in the treatment of synthetic olive mill wastewater (OMW). Different procedures for PMS activation were studied such as activation by Fe(II), radiation (visible and UV-A) and ultrasounds. The operation conditions were optimized by testing pH values, Fe(II) and PMS loads. At optimal conditions ([PMS] = 1600 mg/L, [Fe2+] = 700 mg/L and pH = 5) 60 ± 2% COD removal was achieved. This process shows to be selective since complete degradation of 3,4,5-trimetoxybenzoic acid was obtained after 3 min of reaction. The addition of light, PMS/LED/Fe(II) and PMS/UV-A/Fe(II), did not increase the efficiency of organic matter removal, with 56 ± 2% and 58 ± 1% of COD removal, respectively, comparatively to PMS/Fe(II) (60 ± 2%). PMS activated by ultrasounds led to 52 ± 3% and 23 ± 2% removal of phenolic compounds and COD, respectively, after 60 min. Toxicity tests using Lepidium sativum showed that treatment with PMS/UV-A led to a treated sample with mild inhibition of plant growth.

Investigation of the Possibilities for Removal of Phenolic Toxic Compounds from Water by Nanoporous Carbon from Polymer By-Products

Nanoporous carbon is synthesized on the base of phenol-formaldehyde resin and polyolefin wax, a by-product from industrial production of polyethylene at low pressure. The adsrption of phenol derivates from aqueous solutions on obtained carbon material was studied. The adsorption capacity of the carbon is related to the surface area and composition of the synthesized material, as well as to the nature of the adsorbent. The obtained adsorbent is characterized by high surface area and porosity, and it demonstrates high adsorption capacity towards aromatic compounds. All studied phenolic compounds show high affinity towards carbon, confirming that the retention mechanism occurs via non-specific interactions between the electronic density of the adsorbent and molecules of aromatic pollutants. Electrostatic interactions may also appear depending on pH of the solution pH and charge distribution of the carbons; and these effects has a strong influence on the final performance of the carbon.

Photocatalytic performance of black titanium dioxide for phenolic compounds removal from oil refinery wastewater: nanoparticles vs nanowires

Photocatalytic performance of black titanium dioxide for phenolic compounds removal from oil refinery wastewater: nanoparticles vs nanowires

Coupling magnetite and goethite nanoparticles with sorbent materials for olive mill wastewater remediation

This work aimed at treating OMW by developing an environmentally friendly and cost-effective media capable of removing phenolic compounds upon the interaction between magnetic nanoparticles and sorbent material such as zeolite. Magnetite (Fe3O4) and goethite (FeO(OH)) nanoparticles were prepared using the microemulsion method by using dimethylene-1,2-bis (dodecyl dimethyl ammonium bromide) (CTAB) as a surfactant. The prepared nanoparticles had magnetic properties. X-Ray Diffraction (XRD), and Transmission Electron Microscope (TEM) were used for the structural and morphological characterization. The average crystalline sizes for magnetite and goethite obtained from TEM were 7–16 and 5–14 nm, respectively. The nanocomposite media of magnetite and goethite with zeolite were prepared via coupling natural Jordanian zeolite with magnetic nanoparticles using two approaches; mixing and coating. The adsorption process of phenolic compounds was analyzed by the direct photometric method after treating real samples with nanocomposite media at different conditions. In the batch experiment, the optimum conditions were percent of media to OMW 3%, contact time 3 days, pH of 5, and room temperature. Results revealed that the percent removal of phenolic compounds was 79% and 80% for magnetite/zeolite and goethite/zeolite, respectively using the mixing approach, while with coating approach of magnetite/zeolite, the percentage removal was 75%. A significant improvement of % removal from 61 to 93% was observed with the new composite media of granular activated carbon (GAC) with various percentages to the (Fe3O4, FeO(OH)/zeolite) even at pH of 3.

Selective Removal of Phenolic Compounds by Peroxydisulfate Activation: Inherent Role of Hydrophobicity and Interface ROS.

Selective removal of organic pollutants by advanced oxidation methods has been receiving increasing attention for environmental remediation. In this study, a novel catalyst, which can selectively oxidize phenolic compounds (PCs) based on their hydrophobicity, composed of metal-organic-framework-derived Fe/Fe3O4 and three-dimensional reduced graphene oxide (rGOF) is designed for peroxydisulfate (PDS) activation. This heterogeneous PDS activation system can completely degrade hydrophobic PCs within 30 min. By investigating the hydrophobic properties of eight representative PCs, a positive correlation between the hydrophobicity of PC and the reaction kinetics is reported for the first time. The selective removal stems from the strong interaction between highly hydrophobic PCs and the catalyst. Moreover, the mechanism investigation shows that the degradation reaction is triggered by interface reactive oxygen species (ROS). Our study reveals that the selective degradation of organic pollutants by PDS activation depends on the hydrophilic and hydrophobic properties of the pollutant and catalyst. The reported results provide new insights into a highly selective and efficient PDS activation system for organic pollutant removal.

Specific adsorbents for the treatment of OMW phenolic compounds by activation of bio-residues from the olive oil industry

A series of adsorbents was developed by physical (CO2) and chemical (KOH) activation of two bio-residues: olive stones (OS) and wood from olive tree pruning (OTP). The physicochemical properties of such materials were determined and correlated with their adsorptive performance in the removal of phenolic compounds of olive mill wastewater (OMW). Adsorption isotherms and kinetics of single phenolic acids, as well as the kinetics for competitive multi-compound adsorption, were fitted by applying different models, though Langmuir and pseudo-second order models fitted better the experimental results, respectively. The intraparticle diffusion model pointed out that mesoporosity reduces the influence of phenolic compounds’ restrictions in the external film diffusion of the adsorbent particle–solution interphase, but adsorption capacity linearly increases with the micropore volume accessible to N2 at −196 °C (and also with BET surface area), while diffusion into ultramicropores (<0.7 nm, determined by CO2-adsorption) is slow and presents minor influence on the total adsorption capacity. After saturation, thermal regeneration of spent adsorbents allows the removal of adsorbed products, enabling the reuse of samples whilst maintaining a significant performance.

D-Lactic acid production from Cistus ladanifer residues: Co-fermentation of pentoses and hexoses by Escherichia coli JU15

In this study, glucan-rich solids, and xylose-rich hydrolysates obtained from Cistus ladanifer distillery residues (CLR) were used for d-lactic acid (d-LA) production by the d-lactogenic Escherichia coli strain JU15. Firstly, hemicellulosic hydrolysates obtained by the autohydrolysis process were submitted to dilute sulfuric acid-catalysed post-hydrolysis. The influence of operational conditions on oligosaccharides hydrolysis was assessed by the combined severity parameter (CS) in the range of 1.1–2.3. The optimum post-hydrolysis conditions were found for CS of 1.6 (300 mM H2SO4, 15 min, 121 °C). Subsequent detoxification procedures on post hydrolysed liquors were carried out, where 9.1% (w/v) powdered activated charcoal enabled a full removal of furfural, 5-hydroxymethylfurfural (HMF), and phenolic compounds together with a reduction of acetic acid (37%), and formic acid (27%). Diverse fermentation modes using detoxified and non-detoxified hydrolysates, as well as using previously NaOH delignified glucan-rich solids alone (SHF or SSF) or together with pentoses liquors (SSCF) (5% loading) were performed. For all the tested conditions, both hemicellulose- and cellulose-derived sugars can be efficiently used as the carbon source to produce d-lactic acid by E. coli JU15 with a d-LA yield always surpassing 92 gd-LA/100 g sugars.

Electrocoagulation applied for textile wastewater oxidation using iron slag as electrodes.

The indigo blue dye is widely used in the textile industry, specifically in jeans dyeing, the effluents of which, rich in organic pollutants with recalcitrant characteristics, end up causing several environmental impacts, requiring efficient treatments. Several pieces of research have been conducted in search of effective treatment methods, among which is electrocoagulation. This treatment consists of an electrochemical process that generates its own coagulant by applying an electric current on metallic electrodes, bypassing the use of other chemical products. The purpose of this study was to evaluate the potential use of iron slag in the electrocoagulation of a synthetic effluent containing commercial indigo blue dye and the effluent from a textile factory. The quantified parameters were color, turbidity, pH, electrical conductivity, sludge generation, phenol removal, chemical oxygen demand (COD), and total organic carbon (TOC). The electrocoagulation treatment presented a good efficiency in removing the analyzed parameters, obtaining average removal in the synthetic effluent of 85% of color and 100% of phenol after 25min of electrolysis. For the effluent from the textile factory, average reductions of 80% of color reaching 177.54mg Pt CoL-1, 91% of turbidity reaching 93.83 NTU (nephelometric turbidity unit), 100% of phenol, 55% of COD with a final concentration of 298.8mg O2 L-1, and 73% of TOC with a final concentration of 56.21mg L-1, in 60min of electrolysis. The reduced time for removal of color and phenolic compounds in synthetic effluent demonstrates the complexity of treating the real effluent since to obtain removals of the same order a 60-min period of electrolysis was necessary. The results obtained demonstrate the potential of using iron slag as an electrode in the electrocoagulation process in order to reuse industrial waste and reduce costs in the treatment and disposal of solid waste. Thus, the slag can be seen as an alternative material to be used in electrocoagulation processes for the treatment of effluents from the textile industry under the experimental conditions presented, its only limitation being the fact that it is a waste and therefore does not have a standardization in the amounts of iron present in the alternative electrodes.

Adsorption of Phenol onto Aluminum Oxide Nanoparticles: Performance Evaluation, Mechanism Exploration, and Principal Component Analysis (PCA) of Thermodynamics

The removal of phenolic compounds from aqueous solutions using novel adsorption techniques becomes a key research item. Of those, nanoparticles in particular, the low-cost and the high-strength aluminum oxide nanoparticles showed promising results in pollutant uptake and increase in the adsorption efficiency. This study examined various physicochemical process parameters such as temperature, pH, initial phenol concentration, and adsorbent doses, in addition to the impact of those parameters on the adsorption removal mechanism of phenol. The results highlighted that aluminum oxide nanoparticles successfully exhibited superior phenol removal from an aqueous solution in addition to a high potential regeneration of the consumed nanoparticles by HCl. For the adsorbent mass of 0.5 g, phenol adsorption uptake reached 92%. Kinetic studies performed using several models demonstrated the data best fitting with a pseudo-second-order kinetic model. Examining equilibrium studies of various isotherms, the adsorption data of phenol into aluminum oxide nanoparticles was confirmed to be controlled by film diffusion and best represented by the Langmuir isotherm. The maximum capacity of adsorption was 16.97 mg/g. For thermodynamics studies, the results indicated that the adsorption process can vary between endothermic and exothermic reactions. Such relative differences in heat generation and spontaneity in adsorption processes were demonstrated and confirmed by principal component analysis (PCA). This evidence is key for future investigations for the efficiency of adsorption conditions concerning the contaminant type and adsorbate compounds.

Enhanced Removal of Phenolic Compounds Via Irreversible Sorption Using Manganese Oxides Immobilized on Oxidized Humin

Enhanced Removal of Phenolic Compounds Via Irreversible Sorption Using Manganese Oxides Immobilized on Oxidized Humin

A Comparative Study of Removal of Phenolic Compounds in Wastewater using an Advanced Oxidation Process

A Comparative Study of Removal of Phenolic Compounds in Wastewater using an Advanced Oxidation Process

Coagulation Treatment of Corn Stalk Hydrolysates for Lignin-Derived Phenolic Compounds Removal, Improved Biomethane Production and Antioxidant Preparation

Coagulation Treatment of Corn Stalk Hydrolysates for Lignin-Derived Phenolic Compounds Removal, Improved Biomethane Production and Antioxidant Preparation