Removal Of Azo Dyes Research Articles

Henna plant biomass enhanced azo dye removal: Operating performance, microbial community and machine learning modeling

The bio-reduction of azo dyes is significantly dependent on the availability of electron donors and external redox mediators. In this study, the natural henna plant biomass was supplemented to promote the biological reduction of an azo dye of Acid Orange 7 (AO7). Besides, the machine learning (ML) approach was applied to decipher the intricate process of henna-assisted azo dye removal. The experimental results indicated that the hydrolysis and fermentation of henna plant biomass provided both electron donors such as volatile fatty acid (VFA) and redox mediator of lawsone to drive the bio-reduction of AO7 to sulfanilic acid (SA). The high henna dosage selectively enriched certain bacteria, such as Firmicutes phylum, Levilinea and Paludibacter genera, functioning in both the henna fermentation and AO7 reduction processes simultaneously. Among the three tested ML algorithms, eXtreme Gradient Boosting (XGBoost) presented exceptional accuracy and generalization ability in predicting the effluent AO7 concentrations with pH, oxidation-reduction potential (ORP), soluble chemical oxygen demand (SCOD), VFA, lawsone, henna dosage, and cumulative henna as input variables. The validating experiments with tailored optimal operating conditions and henna dosage (pH 7.5, henna dosage of 2 g/L, and cumulative henna of 14 g/L) confirmed that XGBoost was an effective ML model to predict the efficient AO7 removal (91.6%), with a negligible calculating error of 3.95%. Overall, henna plant biomass addition was a cost-effective and robust method to improve the bio-reduction of AO7, which had been demonstrated by long-term operation, ML modeling, and experimental validation.

Mechanism and performances of methyl orange and Congo red adsorption by MnO2–PVP composite

Abstract Azo dyes are commonly used in textile industries; however, when these dyes cross the permissible limit set by the World Health Organization, they produce many health issues related to the brain, liver, kidneys, respiration, and sexual system. Herein, polyvinyl pyrrolidone (PVP)-supported manganese oxide (MnO2) was studied for azo dye removal from an aqueous medium. The adsorption mechanism study demonstrated that the dye adsorption by MnO2–PVP composite was not only due to the electrostatic force of attraction but also involved the ion exchange amid the hydroxide group and dye molecules. The surface area of the composite (120 m2 g−1) was larger than that of metal oxide (102 m2 g−1). The point of zero charge and surface area were improved from 5.2 and 102 to 5.6 and 120 m2 g−1, respectively. The dye removal capacity of MnO2–PVP composite was significantly higher than that of plain MnO2. The film diffusion control adsorption kinetic mechanism and the kinetic data were well fitted to the pseudo-second-order equation. Experiments were conducted as a function of initial dye concentration (5–200 mg L−1), pH (3–10), temperature (298–328 K), and adsorbent dosage (0.05–0.4 g) in batch adsorption systems. The thermodynamic investigations confirm that the dye adsorption process was endothermic in nature.

Fabrication of cellulose nanocrystals/carboxymethyl cellulose/zeolite membranes for methylene blue dye removal: understanding factors, adsorption kinetics, and thermodynamic isotherms.

This study introduces environmentally-friendly nanocellulose-based membranes for AZO dye (methylene blue, MB) removal from wastewater. These membranes, made of cellulose nanocrystals (CNCs), carboxymethyl cellulose (CMC), zeolite, and citric acid, aim to offer eco-friendly water treatment solutions. CNCs, obtained from sugarcane bagasse, act as the foundational material for the membranes. The study aims to investigate both the composition of the membranes (CMC/CNC/zeolite/citric acid) and the critical adsorption factors (initial MB concentration, contact time, temperature, and pH) that impact the removal of the dye. After systematic experimentation, the optimal membrane composition is identified as 60% CNC, 15% CMC, 20% zeolites, and 5% citric acid. This composition achieved a 79.9% dye removal efficiency and a 38.3mg/g adsorption capacity at pH 7. The optimized membrane exhibited enhanced MB dye removal under specific conditions, including a 50mg adsorbent mass, 50ppm dye concentration, 50mL solution volume, 120-min contact time, and a temperature of 25°C. Increasing pH from neutral to alkaline enhances MB dye removal efficiency from 79.9% to 94.5%, with the adsorption capacity rising from 38.3mg/g to 76.5mg/g. The study extended to study the MB adsorption mechanisms, revealing the chemisorption of MB dye with pseudo-second-order kinetics. Chemical thermodynamic experiments determine the Freundlich isotherm as the apt model for MB dye adsorption on the membrane surface. In conclusion, this study successfully develops nanocellulose-based membranes for efficient AZO dye removal, contributing to sustainable water treatment technologies and environmental preservation efforts.

A comprehensive review on adsorptive removal of azo dyes using functional materials

Abstract The shortage of freshwater resources caused by azo dye pollution is an acute global issue, which has a great impact on environmental protection and human health. Therefore, the use of new strategies for designing and synthesizing green, efficient, and economical materials for the removal of azo dyes is required. Among the various methods for removal of azo dyes, adsorption by using advanced functional materials, including nanomaterials, metal oxides, metal oxides–polymer composite, biomaterials, and porous materials, have attracted significant attention over the past few years because of their capabilities of brilliant removal efficiency, high selectivity, quick response, reversibility, flexibility in operation, and less harmful by-products. In this review, we report the adsorption of azo dyes and general design principles underlying the above-mentioned functional materials and, in particular, highlight the fundamental mechanisms and effect of various environmental conditions; also, current challenges and opportunities in this exciting field have been emphasized, including the fabrication, subsequent treatment, and potential future applications of such functional materials.

Development of a novel bionanocomposite of UiO-66/xanthan gum/alginate crosslinked by calcium chloride for azo dye removal: Insight into adsorption kinetics, isotherms, and thermodynamics

In the present work, UiO-66/xanthan gum/alginate bionanocomposite adsorbent was fabricated using the in-situ crosslinking-gelation method, characterized by different techniques, and finally used for the removal of methylene blue dye from aqueous solution. Adsorption studies were performed using batch experiments and the influencing operational parameters such as contact time, initial pH solution, temperature, initial dye concentration, adsorbent dose, pHPZC, swelling, regeneration, and reuse of the adsorbent were investigated. The various kinetic models (pseudo-first-order, pseudo-second-order, Elovich, and intraparticle diffusion) and isotherm models (Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich) were used to analysis of the experiment results. The results were best fitted to the pseudo-second-order kinetic and Langmuir isotherm models. The maximum adsorption capacity of dye on the adsorbent was obtained at 9.96 mg/g at pH = 11. The value of pHPZC for the adsorbent was obtained at about 8. According to thermodynamic parameters, the dye adsorption was found as spontaneous and endothermic due to the negative value of the ΔG° and ΔH°. After 4 times of reusability cycles, the adsorption efficiency remained above 86 %, which represented a certain regeneration ability. As a result, this research indicates that UiO-66/xanthan gum/alginate bionanocomposite can be utilized as a promising bio-adsorbent for azo dye removal from contaminated wastewater.

Adsorption of anionic and cationic azo dyes from wastewater using novel and effective multicomponent adsorbent

Water pollution is rising worldwide, necessitating innovative and effective treatment solutions. This study introduces a multicomponent/multifunctional novel nanocomposite synthesized from polyethyleneimine (PEI), graphene oxide (GO), bentonite clay, and MgFeAl-layered triple hydroxide (LTH), termed as AGO/Bentonite/LTH. In this study, the synthesized AGO/Bentonite/LTH nanocomposite was utilized to remove azo dyes (methyl orange and crystal violet) from contaminated water samples. The novel AGO/Bentonite/LTH nanocomposite was benchmarked against its pristine materials and their binary combinations. The results indicated the superior adsorption performance of the AGO/Bentonite/LTH nanocomposite relative to all other adsorbents synthesized and examined herein. All the synthesized adsorbents were characterized using different techniques in order to reveal their textural properties, functional groups, morphology, thermal stability, and crystallinity before applying them to decontaminate wastewater samples contaminated with methyl orange (MO) and crystal violet (CV). The Langmuir adsorption isotherm model predicted that the maximum adsorption capacities of CV and MO onto the AGO/Bentonite/LTH nanocomposite are 1705.1 and 1171.8 mg/g, respectively. On the other hand, zeta potential, pH, and FTIR studies suggested the existence of multiple mechanisms governing the adsorption of CV and MO onto the AGO/Bentonite/LTH nanocomposite. Thermodynamic results indicated the endothermicity and exothermicity of CV and MO adsorption, respectively. Another interesting finding reported herein is the high reusability of this nanocomposite as demonstrated by the minimal reduction in the removal of these two pollutants with the repetitive use of the nanocomposite. Additionally, the nanocomposite can also be easily and cheaply regenerated via a few rinses with a diluted NaOH aqueous solution. These interesting observations suggest that the synthesized AGO/Bentonite/LTH nanocomposite is a potent material for efficient dye removal from contaminated water bodies.

Activated rice husk biochar for azo dye removal: batch adsorption, kinetics and thermodynamic studies

<p>The study aimed to analyze the adsorption behaviour of an activated rice husk biochar adsorbent in batch mode to expunge azo dye concentrations depletion from liquid solvents. The biochar adsorbent was formulated using different chemical synthesis processes, and its surface region was assessed using Nitrogen retention. The existence of the particular azo dyes was verified through SEM and EDX examinations. Additionally, XRD analysis was conducted to examine the intensity and crystalline structure of the activated biochar adsorbent. A batch mode study was conducted to ascertain the ideal adsorption parameters, including pH, contact time, biochar dose, and azo dye concentration. The adsorption kinetic studies supported the notion of a favourable adsorption interaction occurring through the mutual influence of the adsorbed matter and the adsorbing substrate. Most isotherm studies were well-fitted with regression values of isotherm models, indicating an adsorption process with non-uniform monolayer formation. Thermodynamic investigations validated that the binding forces between the adsorptive and the adsorbing phase are endothermic, and a significant amount of spent adsorbent was successfully recovered using a strong hydrochloric acid desorption process.</p>

Co-Action of Ionic Liquids with Alternative Sorbents for Removal of Reactive Azo Dyes from Polluted Wastewater Streams

In this study, the facile removal of the chromium-complex-based reactive azo dye C. I. Reactive Black 8 (RB8) from model wastewaters by the co-action of alternative sorbents—biochar (BC) and bentonite (BT)—with ionic liquids such as benzalkonium chloride (BAC) or Aliquat 336 (A336) was studied. The experiments using model RB8-containing wastewater proved that the co-action of BAC with BC is the most promising method of RB8 separation from wastewater containing 1 g L−1 of RB8 dye. The application of 2 g L−1 BC in co-action with 1.5 g L−1 BAC or 1 g L−1 BT in co-action with 2 g L−1 BAC enables the removal of more than 98% of contaminant RB8 after 30 min of action. Similar removal efficiency (RE) was achieved using 40 g L−1 of powdered activated carbon (PAC) after 180 min of action. To reach the same RE using real RB8-containing wastewater, a four times higher dose of BC and a four times higher dose of BAC per gram of removed RB8 were required. The proposed mechanism of RB8 removal by the co-action of alternative sorbents with BAC comprises a parallel effect of (i) sorption, (ii) the formation of less polar ion pairs accompanied by their sorption on an alternative sorbent and (iii) the separation of used alternative sorbents covered with ion pairs. The removal efficiency of organic contaminant(s) from both model and real wastewater was evaluated by VIS spectroscopy applying the Lambert–Beer law and by the determination of chemical oxidation demand (COD) and/or adsorbable organically bound halogen (AOX) parameters.

A novel sugarcane residue-derived bimetallic Fe/Mn-biochar composite for activation of peroxymonosulfate in advanced oxidation process removal of azo dye: Degradation behavior and mechanism

Metal-biochar composites with varying Fe/Mn ratios were synthesized for activating peroxymonosulfate (PMS) oxidative degradation of azo dye Orange G (OG) were investigated. The 1Fe2Mn-BC composite based on 1:2 molar ratio impregnation of Fe/Mn salt concentrations of efficient sugarcane harvest residue showed the best catalytic performance under aqueous pH 3–10 and had the least impacts from coexistence of inorganic anions and humic acids. The OG degradation by 1Fe2Mn-BC/PMS system optimized at catalyst:oxidant:pollutant ratio of 1:1.25:0.5 on g/L basis was found to follow pseudo-first-order kinetic and achieved 100 % degradation efficiency within 30 min. Apparent activation energy for OG degradation by 1Fe2Mn-BC/PMS was 16.91 kJ mol−1, and increasing reaction temperature from 293 to 313 K enhanced degradation rate constant by 49 %. Electron paramagnetic resonance (EPR) and radical quenching experiments revealed dominant non-radical 1O2 and radical O2− pathways in the OG oxidation removal by the 1Fe2Mn-BC/PMS system, although SO4− and OH radicals also participated. XPS spectra of 1Fe2Mn-BC before and after OG degradation indicated dominant surface composition of Fe(III) and Mn(II) valence states over other FeMn-biochar composites. The novel optimized one-step pyrolysis Fe/Mn bimetal biochar composite provides an efficient PMS activation for advanced oxidation process (AOP) treating of azo dyes in wastewater decontamination.

Application of grape seed and Austrocylindropuntia mucilage for the simultaneous removal of azo dye and turbidity from synthetic wastewater: Optimizing experimental conditions using Box-Behnken Design (BBD)

The purpose of this study was to explore the potential of grape seed powder (GSP) as a natural coagulant and Austrocylindropuntia mucilage (AM) as a natural flocculant to efficiently eliminate both Congo red (CR) azo dye and turbidity from synthetic wastewater using coagulation-flocculation technique. The Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) coupled with energy dispersive spectra (EDS) mapping, and X-ray photoelectron spectroscopy (XPS) techniques were used to characterize natural plants employed as well as sludge formed after coagulation-flocculation process. Moreover, response surface methodology (RSM) approach was established via Box-Behnken Design (BBD) to optimize a set of coagulation-flocculation conditions; including GSP dose, AM dose, initial pH, initial CR concentration, initial turbidity, and settling time. RSM-BBD results showed highest removal efficiency of 99.36 % and 95.74 % of CR and turbidity, respectively, achieved under optimum conditions of 0.45 mg L−1 of GSP coagulant, 6 mL L−1 of AM flocculant, at pH of 10, initial CR concentration of 5 mg L−1, initial turbidity of 250 NTU, and after settling time of 120 min. The findings of this work revealed that there are multiple mechanisms involved in CR and turbidity removal, namely hydrogen bonding, electrostatic interactions, π-π interactions, and bridging effect.

Removal of methylene blue azo dye from aqueous solution using biosorbent developed from floral waste

Aim: The present study was carried out to prepare biosorbent from temple floral waste (Tagetes erecta) by pyrolysis and chemical activation method for removal of methylene blue dye from aqueous solution. Methodology: Floral waste of Tagetes erecta collected from the temples were segregated, washed and dried to form biochar by direct pyrolysis and chemical activation method. Followed by physio-chemical analysis of biosorbents the most efficient biochar was selected for the removal of methylene blue dye from aqueous solution. The adsorbent efficiency and percentage removal of methylene blue dye was studied using various doses of biochar (10, 20, 30, 40, 50, 60, and 70 mg 100 ml-1,), effect of pH (2.0 to 4.0, 6.0 to 8.0, and 10.0 to 12.0) and effect of contact time etc. Results: The comparative physio-chemical analysis of the bio chars suggested that the activated charcoal made from temple flower waste by the direct pyrolysis method showed better performance, with its low moisture content (5.3%), low ash content (4.3%), higher yield, larger surface area, and higher porosity (65.3%) as compared to the biochar obtained from chemical activation. The percent adsorption significantly increased (p<0.05) from 76% to 87.0% on increasing biochar dose from 10.0 to 70.0 mg 100 ml-1. On increasing the pH of the solution from 4.0 to 6.0, Methylene blue removal significantly increased (p<0.05) from 88.0% to 91.0%. Interpretation: It is possible to manage floral waste from temples in a sustainable and environmentally responsible manner by converting it into biochar and using it for the treatment of waste water in order to eliminate hazardous dyes. Key words: Activated carbon, Azo dye, Bioremediation, Biochar, Floral waste, Methylene blue

Adsorption Removal of Azo Dye (Methylene Blue) From Wastewater Using Biomaterials with Kinetic Modeling

Industrial wastewater containing dyes poses a significant environmental threat due to their persistence and potential toxicity. Adsorption using bio-based materials offers a promising and sustainable approach for dye removal. This study investigates the effectiveness of bio-based adsorbents derived from coconut husk, banana peels, and orange peels (pretreated with formaldehyde and sulfuric acid) for methylene blue (MB) removal. The adsorbents were characterized using SEM and FTIR. Batch adsorption experiments were conducted to evaluate the MB removal efficiency under various conditions (pH, dosage, temperature, agitation, and contact time). The results showed that the Freundlich isotherm model best described the equilibrium adsorption data, indicating favorable multilayer adsorption. Kinetic studies revealed a pseudo-first-order reaction with an exceptional removal efficiency of 99.94%. Notably, the R-squared value of 0.99992 signifies an excellent fit of the model to the experimental data. These findings demonstrate the remarkable potential of bio-based materials for MB removal from wastewater. This approach offers an eco-friendly and cost-effective solution for dye remediation in the textile and dyeing industries, contributing to cleaner water resources.

Ecologically viable carbon nano-onions for the efficient removal of methyl orange azo dye and its environmental assessment

The performance of carbon nano-onions in removing methyl orange dye from wastewater.

Adsorptive removal of Congo Red dye from its aqueous solutions by tetraethylenepentamine modified peanut husks composite beads

The ability of tetraethylenepentamine modified peanut husks (TEPA-PH) composite beads in the removal of an anionic azo dye, Congo Red (CR) was studied. In batch adsorption studies, various parameters such as contact time, initial dye concentration, pH, dosage and agitation rate were included to study their influence towards the adsorption process. The TEPA-PH composite beads formed were thoroughly characterized by using several techniques which includes Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy, Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). The experimental data followed the pseudo-second-order kinetic model with R2 close to unity. Among the isotherm models, the experimental data is best fitted to Freundlich isotherm model by having R2 of 0.9948. The maximum adsorption capacity was determined to be 19.5695 mg/g using the Langmuir model. The significant factors were selected using the Plackett-Burman (PB) design and the optimization of the adsorption model was done using the Response Surface Methodology (RSM). With optimum conditions of 180 min of contact time, 62.5 mg/L of initial dye concentration and 0.35 g of dosage, the percentage uptake of CR can reach 77.11%.

Removal of anionic azo dye from wastewater using Fe3O4 magnetic nanoparticles adsorbents in a batch system

This work investigates removing the anionic azo dye from wastewater using Fe3O4 magnetic nanoparticle adsorbents in a batch system. The effects of adsorbent dosage (0.1–0.5 g/L), pH (2−10), dye concentration (5–45 mg/L), contact duration (0–140 min), and shaking speed (100–180 rpm) on the removal (adsorption) efficiency at 23 °C were investigated. Besides the kinetic and isothermal studies were applied as well to improve commercial adsorbents’ performance in removing anionic dyes. Fe3O4 magnetic nanoparticles achieve a maximum azo dye removal (adsorption) efficiency of 99.99% at the optimum values of the investigated parameters: 3 g/L of adsorbent dose, 5 mg/L dye concentration, pH 2, and 180 rpm in 120 min at 23 °C. Langmuir adsorption isotherm has the highest correlation coefficient (R2 = 0.977) compared to Freundlich, and Temkin isotherms; the maximum absorption of azo dye is estimated to be 0.4158 mg/g. The values of the equilibrium parameter (RL) in the Langmuir isotherm model are between 0 and 1, indicating the Langmuir isotherm's favorability. The Fe3O4 magnetic nanoparticle adsorption rates follow pseudo-first-order adsorption kinetics, with R2 = 0.973.

Electrocoagulation-based AZO DYE (P4R) Removal Rate Prediction Model using Deep Learning

This article presents a study on the effectiveness of electrocoagulation (EC) for the removal of azo dyes from wastewater. The analysis was performed using a combination of statistical methods, including density estimation, correlation analysis, and deep learning for electrocoagulation performance prediction. The results showed that electrocoagulation was able to effectively remove azo dyes from the wastewater, considering the energy consumption and the mass of flocs being important factors in the process. Deep Learning (DL) is used to build our predictive model using the datasets collected during the experimentation stage. Overall, the findings suggest that electrocoagulation is a promising technique for the treatment of wastewater containing azo dyes, and that the use of statistical and machine learning methods can aid in the optimization of the process.

Chitosan/PVA-supported silver nanoparticles for azo dyes removal: fabrication, characterization, and assessment of antioxidant activity

The photocatalytic activity of AgNPs@chitosan/PVA nanocomposite was tested against different dyes such as methylene blue, methylene orange, and methylene red as an effective photocatalyst.

Dual-functional Polyvinylidene Fluoride Beta Cyclodextrin-Grafted Graphene Oxide Mixed Matrix Membranes for Removal of Anionic Azo Dyes

Mixed matrix PVDF polymeric membranes were incorporated with β–CD grafted graphene oxide (GO) nanocomposites (β–CD-g-GO) via nonsolvent induced phase separation method and used in the adsorption of congo red (CR) and methyl orange (MO) dyes. The incorporation of β–CD-g-GO (6 wt%) was found to improve the membrane physico-chemical properties and performance. The water content was increased by 24.26%, contact angle reduced from 84.17 to 62.97° while flux increased from 12.42 to 275.03 L m−2 h−1 bar−1. The membranes were able to remove 100% of CR at pH 7 and 99.4% of the MO dye at pH 5 within 240 min. The adsorption kinetics and isotherms were well fitted to the pseudo second-order kinetic model and Freundlich isotherm model respectively. These results indicated that the adsorption of both dyes occurred via chemisorption and in a multilayer on a heterogeneous surface of the membranes. According to these findings, it was concluded that the adsorption mechanism was due to hydrogen bonding interactions between nitrogen and hydroxyl groups, inclusion complexation introduced by β–CD molecules and electrostatic interactions, between the negatively charged oxygen-containing groups of the membrane and the positively charged nitrogen and azo-linkages of the dye molecules. PVDF/β–CD-g-GO membranes have shown excellent adsorption efficiency towards azo dyes. This work indicates that the embedding of adsorptive GO-β–CD nanocomposites in PVDF membranes can remove anionic dyes from wastewater treatment.

Decoration of silver on ZnS for enhancement of sunlight-driven photodegradation of reactive red azo dye and norfloxacin antibiotic

High charge carrier recombination rate is the major difficulty affecting low photocatalytic performance of the UV-responsive ZnS photocatalyst. To overcome the problem, well dispersion of noble metals on the ZnS surface can be regarded as one of the useful strategies to enhance the photocatalytic efficiency. This is due to a synergy of creation of heterojunction structure and surface plasmon resonance effect. In the present work, the surface of the hydrothermally grown ZnS photocatalyst was modified with 10 wt %silver. The hexagonal Ag/ZnS photocatalyst provided high sunlight-active photocatalytic performance toward removal of anionic azo dye and norfloxacin antibiotic with the efficiency of about 99 % and 70 %, within 120 min, respectively. The improvement of the resultant photoactivity is attributed to increasing of charge separation capacity at the interface. Well distribution of silver on ZnS surface results in the generation of the Schottky barrier at the Ag/ZnS interface. This will end up with the increment of quantum efficiency and enlargement of the photocatalytic activity. Additionally, after modification of ZnS surface by addition of silver, a red shift in the light absorption toward visible region was found. This is assigned to the effect of surface plasmon resonance (SPR) of Ag on ZnS surface. The synthesized Ag/ZnS reveals high structural stability with enhanced performance even after the fifth cycle. This work demonstrates a new avenue for creation of a silver-modified ZnS for complete degradation of toxic organic contaminants including dyes and antibiotics by use of the abundant solar energy.

Rosemary particle as a new green additive to improve polysulfone membrane separation performance in removal of organic pollutants

This study used rosemary particles to make PSf nanofiltration membranes with antifouling properties, for medicinal pollutants and Azo dyes removal. The extract of rosemary plant was extracted using the Soxhlet process. Then homogeneous rosemary particles were embedded in the PSf membrane matrix as a green additive using the NIPS method. Characterization of the structure and morphology of rosemary particles and membranes was performed by FTIR, XRD, UV–Vis, FE-SEM, STA, DLS, ATR-FTIR, SEM, AFM, Zeta potential and TGA analyses. The results indicated the formation of homogeneous, hydrophilic, and spherical particles with a negative surface charge as well as physical stability in aqueous solutions and high thermal stability with a particle size of about 229 nm. Adding the optimal amount of rosemary particles increased the hydrophilicity (reduced water contact angle from 60.55° to 52.15°) and porosity (increased from 69.3 to 91.7%). Also, by adding 1 wt% of rosemary particles, the permeability of the membrane increased by 3.5 times. The increase in mean pore radius (from 4.77 to 6.08 nm), smoother surface of modified membranes and negative charge on the membrane surface proved this improvement. Therefore, the amount of 1 wt% caused the best flux performance of pure water (from 126 to 359 LMH) and BSA solution (from 104.5 to 202.3 LMH). Moreover, RE/PSf membranes showed a high rejection for azithromycin: 81.98%, cefixime: 58.07%, O II: 71.75, RY 160: 81.71 and RB 5: 93.69%.