Removal Of Phenolic Compounds Research Articles

Study of the experimental and microscopic mechanism of the removal of phenolic compounds from wastewater based on hydrophobic deep eutectic solvents

Dephenolisation has been a key environmental concern; therefore, separating and recycling phenolic compounds from wastewater can reduce environmental harm and the consumption of resources, respectively. Herein, we selected three hydrogen bond acceptors (HBAs) and three hydrogen bond donors (HBDs) with excellent industrial prospects, which were widely sourced, and combined them as nine hydrophobic deep eutectic solvents (HDESs) to perform liquid–liquid extraction (LLE) experiments and molecular simulation studies on model wastewaters containing phenol and catechol. The preliminary screening of HDESs was carried out by conducted with quantum chemical simulations using σ-Profiles, and the microscopic mechanism of the extraction process using HDESs was analysed through molecular dynamics (MD) simulations based on radial distribution function, spatial distribution function, mean square displacement and interaction energy results. Guided by the above molecular simulation results, experimental studies on LLE using HDESs were further conducted to determine the optimal conditions of the experimental operation, including the types and ratios of HBAs and HBDs, feed ratios between the HDESs and model wastewater, and extraction temperatures. The experimental studies revealed that the extraction efficiency of octanoic acid − geraniol (molar ratio 1:3) on a 0.6 % (mass concentration) phenol and catechol model wastewater at 25℃ could reach > 96 %. Moreover, the results were consistent with that of MD simulation. The above methodologies provide a reliable basis for resolving similar problems.

Removal of phenolic inhibitor compounds from hydrolysates and post-fermentation broths by using a hydrophobic magnetic deep eutectic solvent

Hydroxymethylfurfural (HMF), furfural (FF), hydroquinone (HQ), and vanillin (VAN) are among the main inhibitors generated during most of biomass pre-treatments prior to fermentation processes. They are recognized as toxic to several fermentative microorganisms and therefore cause a decrease in biohydrogen or biofuel production (after hydrolysis). Moreover, if they are released into aqueous solutions (after fermentation), they can be detrimental to the ecosystem. In this research, a new method for removing these inhibitor compounds from the broth after hydrolysis and fermentation is proposed. A hydrophobic magnetic deep eutectic solvent (HMDES), based on menthol: nonanoic acid in a mole ratio of 2:1 was prepared and magnetized with Fe3O4 nanoparticles and applied for effective sorption and removal of these inhibitors from the broth after fermentation and for biomass hydrolysates. Parameters affecting sorption, such as pH, volume of the inhibitors, initial concentration of inhibitors, volume of HMDES, temperature, stirring speed, and contact time, were studied and optimized. Under optimum conditions, the removal efficiency for HQ, HMF, FF, and VAN was obtained as 92.97, 86.72, 82.86 and 95.12% for the model samples. In addition, the removal efficiency of real samples after hydrolysis and fermentation for HQ, HMF, FF and VAN were higher than 83.3, 71.42, 69.99 and 76.80%, respectively. The studies on HMDES regeneration revealed that the removal efficiency remained constant even after undergoing 13 cycles of regeneration. The mechanism of inhibitor removal suggests that hydrogen bonding or van der Waals interactions may serve as the predominant factor influencing the extraction process.

Catalytic green synthesis of Tin(IV) oxide nanoparticles for phenolic compounds removal and molecular docking with EGFR tyrosine kinase

In this study, tin dioxide nanoparticles (SnO2 NPs) were successfully synthesized through an eco-friendly method using basil leaves extract. The fabricated SnO2 NPs demonstrated significant adsorption capabilities for phenol (PHE), p-nitrophenol (P-NP), and p-methoxyphenol (P-MP) from water matrices. Optimal conditions for maximum removal efficiency was determined for each phenolic compound, with PHE showing a remarkable 95% removal at a 3 ppm, 0.20 g of SnO2 NPs, pH 8, and 30 min of agitation at 35 °C. Molecular docking studies unveiled a potential anticancer mechanism, indicating the ability of SnO2 NPs to interact with the epidermal growth factor receptor tyrosine kinase domain and inhibit its activity. The adsorption processes followed pseudo-second order kinetics and Temkin isotherm model, revealing spontaneous, exothermic, and chemisorption-controlled mechanisms. This eco-friendly approach utilizing plant extracts was considered as a valuable tool for nano-sorbent production. The SnO2 NPs not only exhibit promise in water treatment and also demonstrate potential applications in cancer therapy. Characterization techniques including scanning electron microscopy, UV–visible spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction spectroscopy (XRD), and energy-dispersive X-ray spectroscopy (EDAX) provided comprehensive insights into the results.

Investigation of different polymeric membranes for removal of phenol from aqueous environment using pervaporation technique

The removal of phenolic compounds from the water was of great importance due to their high toxicity. In this study, the separation of phenol from an aqueous environment by pervaporation technique using (PVA) polyvinyl alcohol, (CA) cellulose acetate, and (PVDF) polyvinylidene fluoride membranes was tested. The effect of feed concentration up to 9000 ppm, operating temperature from 25 to 65 °C, and flow rate ranging from 2 to 6 L h−1 on the separation performance was investigated. It was found that the CA membrane possessed a higher water flux of 348.25 kg m−2 h−1 and a separation factor of 49 compared to PVDF, and PVA/SA membranes at 65 °C and a flow rate of 6 L h−1. The properties and morphology of membranes were observed using mechanical properties, contact angle, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The results showed that CA has a lower contact angle of 48.3° indicating the hydrophilicity nature of the membrane, which enhances the separation process and explains the increases of water flux. Moreover, the mechanical properties test indicated that the mechanical strength of CA has a maximum tensile strength of 65.5 MPa and an % elongation of 48% compared to PVDF and PVA/SA which indicates lower roughness, manifesting its improved anti-fouling properties.

Removal and recovery of phenolic compounds from OMW by a cationic resin

Olive mill wastewater (OMW) is rich in valuable compounds such as phenolic compounds. Amberlite@HPR1100 was applied as adsorbent to recover these added-value compounds from OMW. For synthetic OMW, Langmuir isotherm and pseudo-second order kinetic model were able to predict the experimental data instead for real effluent, were the Freundlich isotherm and the pseudo-first order kinetic model the best fits. The continuous process was also studied, for real OMW the tbp, tst and tex were 1.27 min, 84.4 min and 575 min, respectively. After 645 min of adsorption, 42 % of phenolic content was adsorbed into the resin. An industrial column for recovering phenolic compounds from OMW was designed, which should have around 5 m and 0.6 m of height and diameter, respectively, filled with 112 kg of resin (dry basis). The desorption process for real OMW with acetone 80 % recovery was accomplished after 5 h of contact.

Spherical Lignin-Derived Activated Carbons for the Adsorption of Phenol from Aqueous Media.

In this work, a synthesis and activation path, which enabled the preparation of spherical activated carbon from a lignin precursor, characterized by high adsorption capacity in the removal of phenolic compounds from water, was successfully developed. Two industrial by-products, i.e., Kraft lignin and sodium lignosulfonate, were used to form spherical nanometric lignin grains using pH and solvent shift methods. The obtained materials became precursors to form porous activated carbons via chemical activation (using K2CO3 or ZnCl2 as activating agents) and carbonization (in the temperature range of 600-900 °C). The thermal stabilization step at 250 °C was necessary to ensure the sphericity of the grains during high-temperature heat treatment. The study investigated the influence of the type of chemical activator used, its quantity, and the method of introduction into the lignin precursor, along with the carbonization temperature, on various characteristics including morphology (examined by scanning electron microscopy), the degree of graphitization (evaluated by powder X-ray diffraction), the porosity (assessed using low-temperature N2 adsorption), and the surface composition (analyzed with X-ray photoelectron spectroscopy) of the produced carbons. Finally, the carbon materials were tested as adsorbents for removing phenol from an aqueous solution. A conspicuous impact of microporosity and a degree of graphitization on the performance of the investigated adsorbents was found.

Removal of phenolic compounds from sugarcane syrup and impact on Saccharomyces cerevisiae fermentation for β-farnesene production.

This work aimed to study for the first time the effects of phenolic compounds from sugarcane syrup on Saccharomyces cerevisiae β-farnesene fermentation by removing them from this feedstock. Syrup purification was optimized through a central composite design using five types of activated charcoal: three contact times (1-24h) and three adsorbent concentrations (10-150gL-1 ). The optimal purification condition-charcoal pellets at 115gL-1 and contact time of 12.5h-led to 96.7% of phenolic compounds removal and 43.7% of syrup recovery. The effects of reducing phenolic content from approximately 7.0-0.3mgL-1 in sugarcane syrup on yeast fermentation varied with the scale. An increase in biomolecule productivity was only observed in shake-flasks (11%) and in biomass productivity only in the 2 L bioreactor (12%). Thus, phenolic compounds from sugarcane syrup do not influence β-farnesene production at a large scale under the conditions tested.

Activated-hydrochar derived from olive mill wastes for the removal of phenolic compounds from olive mill wastewater

Activated-hydrochar derived from olive mill wastes for the removal of phenolic compounds from olive mill wastewater

Achieving ultra-trace analysis and multi-light driven photodegradation toward phenolic derivatives via a bifunctional catalyst derived from a Cu(i)-complex-modified polyoxometalate

A polyoxometalate-based bifunctional catalyst was applied for the “nM” detection of phenolic derivatives, and exhibited good removal efficiencies under UV light, visible light, NIR light, full spectrum light, and sunlight irradiation to phenol.

Electron-deficient Fe3O4@AC-NH2@Cu-MOF nanoparticles for enhanced degradation of electron-rich benzene derivatives via synergistic adsorption and catalytic oxidation.

Benzene derivatives in wastewater have negative impacts on ecosystems and human health, making their removal prior to discharge imperative. In this study, Fe3O4@AC-NH2@Cu-opa (AC-NH2 = aminoclay, Cu-opa = [Cu(opa)(bipy)0.5(H2O)]n (H2opa = 3-(4-oxypyridinium-1-yl) phthalic acid)) nanoparticles (NPs) were synthesized as adsorbent and catalyst for phenolic compound removal from wastewater. Fe3O4@AC-NH2@Cu-opa NPs demonstrated outstanding performance in the adsorption of phenol, exhibiting a remarkable adsorption capacity of up to 166.39 mg g-1 according to the Langmuir model. The composite also exhibited higher Fenton activity toward the degradation of electron-rich organic phenolic pollutants, with a rate approximately 3.4 times higher than that of Fe3O4 alone. The high catalytic activity of the composite was attributed to the large surface area and abundant active sites of the 2D charge-separated Cu-MOF. Meanwhile, the superparamagnetism of the Fe3O4 core enabled magnetic recollection and reuse without any significant loss of activity. Therefore, use of Fe3O4@AC-NH2@Cu-opa/H2O2 shows potential in an efficient method for the removal of phenolic compounds from wastewater.

Development of new effective activated carbon supported alkaline adsorbent used for removal phenolic compounds

Phenolic (phenol) compounds are the major contaminates in wastewater, which can have a considerable negative influence on the environment and health of human. Adsorption is an efficient process that is widely applied in order to eliminate phenol in wastewater. In recent, Adsorption process has acquired a lot of attentiveness owing to its relative moderate operating conditions. However, adsorption process needs considerable ameliorations in terms of adsorbent modification, process type, productivity, and conversion rate. This work studies the development of a fast and effective adsorption process in a fixed bed adsorption column (FBAC) in order to reach safe and continuous elimination of phenolic compounds. Several adsorption parameters (reaction temperature, adsorbent bed height, feed flow rate and kind of adsorbent) were studied to achieve the highest removal of phenolic compounds. The adsorption process was conducted in the presence of two type of adsorbents (activated carbon (AC), and KOH/AC), 73% and 94% of phenol elimination were attained, respectively, at 10 cm bed height, 1 ml/s feed flow rate, and 75 °C reaction temperature. The adsorbents activity was investigated after six consecutive adsorption cycles at the best process conditions, and the adsorbents show high stability in terms of phenolic compounds adsorption. After that, the spent adsorbents were regenerated by utilizing various solvents (methanol, ethanol and iso-octane), and the results show that iso- octane achieved highest regeneration efficiency. The adsorption process was implemented in the adsorption column that the performance is possibly to be adjusted at an industrial scale since it can be scaled up predictably.

Regulating composition of Mn-CeOx nanoparticles with ultra-small sizes on Al2O3 for enhanced catalytic ozonation

Herein, Al2O3 supported ultra-small Mn-CeOx nanoparticles (Mn-CeOx/Al2O3) are prepared by a facile impregnation method for removal of phenolic compounds via catalytic ozonation. Mn and Ce species are in the form of polyvalent oxide nanoparticles with an average size of 0.9 nm. The removal efficiency of total organic carbon for phenol-containing model wastewater by Mn-CeOx/Al2O3 shows a volcano relationship by changing the mass ratio of Mn and Ce, and reaches up to the peak value when the mass ratio is 5:5. The cycle stability tests suggest the removal efficiency of Mn-CeOx/Al2O3 could maintain at 90.16 % after 5 circles. The enhanced performance should be attributed to the optimized magnetism and accelerated charge transfer by composition regulation. The magnetic strength changing affects the adsorption mode of O3, while the redox cycle of Mn(IV)/Mn(III) and Ce(IV)/Ce(III) could enhance the activation of O3 to produce more ·OH and 1O2 for the organic molecules mineralization.

Sustainable waste utilization: Geopolymeric fly ash waste as an effective phenol adsorbent for environmental remediation

Rapid industrialization and urbanization generate significant waste, including fly ash, posing environmental challenges. Utilizing these materials is essential to mitigate impacts and promote sustainable development. This research paper focuses on the innovative application of geopolymeric fly ash (GEOFA) waste modified with titanium oxide (TiO2) (GEOFA-TiO2) as a promising adsorbent for the removal of phenol compounds from contaminated water. Analysis showed that the modification process resulted in the formation of functional groups such as -OH, which aided in the adsorption process. Adsorption studies were conducted to evaluate the influence of pH, temperature, and concentration on phenol removal. The maximum percentage removal of phenol was achieved at optimum conditions of pH 6 and a temperature of 25 °C, with an adsorption capacity of 166.7 mg/g. The adsorption process followed the Langmuir model, suggesting a monolayer adsorption mechanism and the thermodynamic studies revealed that the phenol adsorption onto GEOFA-TiO2 was an endothermic process with a promising affinity between phenol and the adsorbent. This study demonstrates the effective use of modified fly ash-based adsorbents to remove phenolic contaminants. By repurposing waste materials, this research addresses waste management challenges and promotes sustainable practices, reveling their potential for environmental remediation.

Performance improvement of metagenomic laccase immobilized on nanocellulose-reinforced hydrogel nanocomposites for enhanced delignification and detoxification

Immobilization enhances the potential of laccases to degrade lignocellulosic waste, thereby providing an efficient approach for delignification and detoxification. In this study, a comparative analysis of the activity of free and immobilized metagenome-derived laccase (PersiLac2) on nanocellulose (NC)-reinforced hydrogel nanocomposites was performed, and the effectiveness of immobilized laccase in delignification, particularly in relation to rice straw degradation and phenol production, was evaluated. After 1 h of incubation at 90 °C, the immobilized laccase retained 80% of its activity, exhibiting 1.6-fold higher retention than that of the free enzyme. At alkaline pH (8.0–9.0) the free enzyme demonstrated enzymatic activity of 55–65%, while this value was 59–73% for the immobilized form. Immobilization also facilitated easy recovery and reuse of PersiLac2. After 15 cycles, 76.64% of enzyme activity was preserved, highlighting the improved reusability and stability of the immobilized enzyme. Furthermore, leaching tests revealed that the hydrogel-enzyme conjugate maintained a strong connection, with only approximately 20% of the enzyme being leached after 240 min of incubation at 60 °C. This indicates a strong connection between the hydrogel and enzyme structure. Additionally, our study also employed SEM and FTIR analyses, demonstrating the superior performance of immobilized PersiLac2 compared to its free form in the treatment of rice straw. Furthermore, the immobilized enzyme reduced soluble phenols (77.45%) in the slurry of acid-pretreated rice straw. Overall, our findings highlight the potential of immobilizing PersiLac2 on hydrogel nanocomposites to improve enzyme stability, activity, and reusability. This study demonstrates a promising pathway for efficient delignification, phenolic compound removal, and enhanced biomass processing and waste management.

Phenol removal from aqueous solution using advanced oxidation process enabled by a hybrid system: UV/H2O2/O3/TiO2

The need for healthy and pollution-free water is vital given the world’s industrialization and population explosion. The removal of chemical pollutants, especially phenol and phenolic compounds, from urban and industrial wastewaters is of particular importance due to their high water solubility and toxicity. Previous physicochemical techniques for phenol removal are no longer cost-effective. Advanced oxidation processes (AOPs) using various oxidizing agents have been recently recognized as an effective method for removing organic compounds through mineralization. The present work evaluated the phenol (100 ppm) removal from aqueous solutions through photooxidation systems of UV exposure, UV/TiO2, O3, O3/TiO2, H2O2, H2O2/UV, H2O2/TiO2, H2O2/TiO2/O3 and H2O2/TiO2/O3/UV. The results showed a decrease in the phenol concentration by almost half using UV, UV/TiO2, O3, O3/TiO2, H2O2, H2O2/UV and H2O2/TiO2 within 50 min. The phenol concentration reached 50 and 71 ppm using H2O2/TiO2/O3 system within 50 and 70 min, respectively. The UV/H2O2/O3/TiO2 system reduced the phenol concentration to zero after 40 min. The findings revealed that the AOP enabled by the UV/H2O2/O3/TiO2 combined system caused the complete removal of phenol, highlighting the capacity of the proposed system to remove toxic aromatic compounds such as phenol released during the wastewater treatment process.

Influence of Thermal and Chemical Treatment on Biosorbent from Rice Husk and Its Application in Removal of Resorcinol from Industrial Wastewater

The removal of phenolic compounds is of great importance because of their toxic nature and potentially harmful effects on the environment and human health. This study examines the use of rice husk as a biosorbent for eliminating phenolic compounds, particularly resorcinol, from industrial wastewater. Three types of rice husk, namely raw rice husk (RRH), chemically treated rice husk (CTRH), and thermally treated rice husk (TTRH), are utilized after grinding and methanol treatment. Characterization techniques including X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and optical microscopy are used to analyze the rice husk-based adsorbents. The microscopic analysis reveals the presence of nano-pores in TTRH and the existence of carbonyl and hydroxyl groups in all sorbent samples. XRD analysis confirms the presence of silica in biosorbents. This study also examines the influence of dosage and initial concentration on resorcinol sorption. Optimized dosages of 0.5 g (RRH), 0.5 g (CTRH), and 1.5 g (TTRH) result in sorption capacities of 14 mg/g (RRH), 11 mg/g (CTRH), and 5 mg/g (TTRH). Isotherm analysis indicates that the Langmuir isotherm best describes the sorption behavior of TTRH, while the Freundlich isotherm is observed for CTRH, and both RRH and CTRH follow the Temkin isotherm.

Performance and mechanism of enhanced phenolic compounds treatment via mycelial pellets

AbstractBACKGROUNDBiological enhancement in organic wastewater treatment is currently considered an effective and economical method. As a biomass carrier, mycelial pellets are attracting increasing attention, with substantial progress recently being made. To investigate their bioaugmentation effect as a biomass carrier, mycelial pellets with immobilized phenol‐degrading bacteria were applied in a sequencing batch reactor. The phenolic compound removal efficiency of the mycelial pellet‐enhanced system was then studied and compared to the control aerobic activated sludge‐enhanced system. Finally, the settling velocity, internal structure, and surface properties were studied to explore the main bioaugmentation mechanisms of the mycelial pellets.RESULTSThe stable degradation effects of phenolic compounds and total organic carbon (TOC) were observed in both systems. In the mycelial pellet system, the biological removal efficiency was approximately 0.5 mg phenolic compounds L−1 d−1MLSS−1 and 0.4 mg TOC L−1 d−1MLSS−1, which was higher than the aerobic activated sludge system. Bioaugmentation by the pellets was mainly attributed to the structure of the connected macropores, the electrostatic attraction of positive charges, the adsorption of functional groups on the hypha surface, and flocculation due to the extracellular polymeric substances secreted on the pellet.CONCLUSIONThe excellent phenolic compound removal efficiency and bioaugmentation effect of the mycelial pellets suggest their potential to enhance organic wastewater treatment as a biomass carrier. © 2023 Society of Chemical Industry.

Enhanced removal of phenolic compounds by ferrate(VI): Unveiling the Bi(III)-Bi(V) valence cycle with in situ formed bismuth hydroxide as catalyst

The use of 2-hydroxybenzophenone (2-HBP) in personal care products is of great concern due to its potential negative effects on the ecosystem and public health. This paper presents the degradation of 2-HBP by bismuth(III) (Bi3+)-ferrate(VI) (FeVIO42−, Fe(VI)) (Bi3+-Fe(VI) system). Experimental studies at different pH and dosages of Bi3+ and Fe(VI) showed that the Bi3+-Fe(VI) system increased the degradation rate and removal efficiency of 2-HBP compared to Fe(VI) alone. The in situ formed flake-like white flocculent precipitate of Bi(OH)3 showed catalytic performance through the Bi(III)-Bi(V)-Bi(III) valence cycle which was demonstrated through spectroscopic measurements. The hydrogen transfer-mediated reactions between Fe(VI) and Bi(OH)3 as well as subsequent formation of Bi(V) were supported by performing density functional theoretical (DFT) calculations. Seventeen identified transformation products of 2-HBP by Fe(VI) with and without Bi3+ revealed hydroxylation, bond breaking, carboxylation, and polymerization reaction pathways. Significantly, Bi3+ facilitated the polymerization reaction and the dioxygen transfer-mediated hydroxylation reaction pathways. The ions (anions and cations) and humic acids (HA) present in the Bi3+-Fe(VI) system had minimal influence on the removal efficiency of 2-HBP. Reusability tests and use of real water samples as well as toxicity assessments of transformation products unveiled the practical application aspect of the Bi3+-Fe(VI) system. Finally, the results showed that the system exhibits good removal efficiency for all 12 phenolic compounds, indicating theuniversality. The Bi3+-Fe(VI) system may be an easy-to-implement cost-effective method for the catalytic degradation of benzophenones by Fe(VI).

Peroxidase-Conjugated Boron Nitride-Based Magnetic Nanowires For Phenolic Compounds Removal

Peroxidase-Conjugated Boron Nitride-Based Magnetic Nanowires For Phenolic Compounds Removal

Removal of Phenolic Compounds from Industrial Wastewater Through Adsorption Techniques

Removal of Phenolic Compounds from Industrial Wastewater Through Adsorption Techniques