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Background and purpose: According to thetheory ofsustainable development, protect the environmentforcurrent and futuregenerationsisinevitable. Chromium (VI) is one of the pollutant of waterthatcauseharm totheaqueous environmentandrisksfor human health, animalsand plants. The purpose of this study was tosynthesis of Fe3O4 nanoparticlesand evaluateofCr (VI) adsorptionon Nanoparticle ssynthesizedasanadsorbent. Materials and methods: Inthisexperimental- laboratorystudy, nanoparticleswere synthesized bychemicalco-precipitation method and as an adsorbent was studiedforadsorptionof Cr (VI).The resulted nanomaterials were characterized by SEM, XRD and FT-IR. Effects ofpH, contacttime, adsorbentdoses andinitial Cr (VI) concentration werestudied. The resulting data were described by the Langmuir and Freundlich isotherm models and for Data analysis was used from Excel software. Results: The results showedthat thecharacterization ofnanoparticleswereas expectedandthe best of removal performance in pH= 2, at contact time equal10 min, adsorbentdose of 1g/L and initial Cr (VI) concentration of50 mg/L.The Pattern of Cr (VI) adsorption was fitted with the Freundlich model and Adsorption processes followed the pseudo second-order kinetics. Conclusion: chemical co-precipitation Synthesis methodbased onlow power consumptionandShort time isaappropriate methodandFe3O4nanoparticlessynthesizedby this methodcan be used as asuitable optionfor theadsorptionof Cr (VI).

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Introduction: Industrial wastewater is one of the major environmental pollutants. Discharge of the colorful industrial effluent into the receptive waters leads to eutrophication and has mutagenic and carcinogenic properties. Therefore, the aim of this study was to investigate the removal of acid blue113 from aqueous solutions by Canola (Brassica Napus) waste. Materials and Methods: This is an experimental-lab study. Canola waste was used as an adsorbent to remove the acid blue113 dye. The effect of various parameters on adsorbent performance was investigated. The isotherms of adsorption were determined. The dye concentration was measured in wavelength of 566 nm by spectrophotometer. Results: The results indicated that the removal rate of dye increased with increasing the contact time and dose of adsorbent but the amount of adsorbed dye per gram adsorbent (qe) decreased. The removal rate increased with decreasing the initial concentration of dye, too. In the optimum state, the adsorbent could adsorb about 99 percent of the dye. The data of adsorption were best fitted to Langmuir isotherm. Conclusion: This study indicated that Canola waste can be used as an effective and inexpensive adsorbent to treat of textile effluents

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Abstract Background and purpose: Natural zeolites are widely used for the purification of water and wastewater. Nevertheless the selectivity of clinoptilolite (a common zeolite mineral) for cadmium is known to be particularly low. In order to enhance the zeolites’ sorption capacity for cadmium, we treated natural clinoptilolite with sulfuric acid solutions and investigated the sorption of cadmium to acid-modified clinoptilolite by a series of batch experiments. Materials and methods: The batch method has been employed using metal concentrations in solution ranged from 25 to 100 mg/l and adsorbent ranged from 0.2 to 1.8 g/l. The influence of acid concentration, contact time, solution pH, adsorbent particle size, initial cadmium concentration and adsorbent mass has been studied. Results: It was found that the acid modified clinoptilolite exhibits higher adsorption to cadmium than unmodified clinoptilolite and adsorption of the cadmium is influenced by several parameters such as cadmium initial concentration, adsorbent dosage and solution pH. Maximum absorption efficiency was achieved at pH of 6. Meanwhile maximum absorption efficiency of acid modified clinoptilolite in cadmium removal shows improvement due to 1 molar sulfuric acid. The equilibrium adsorbed amount also increased with the initial concentration of the metal ions, as expected. Adsorption capacities of the acid- modified clinoptilolite for cadmium increased as the particle size decreased down to 0.5 mm in diameter, but no difference was observed for a diameter less than 1.5 mm. Conclusion: The best results in terms of efficiency are obtained for the clinoptilolite modification with 1 molar sulfuric acid and it was more favorable than natural clinoptilolite in removing cadmium and thus was a better adsorbent as low-cost alternatives in wastewater treatment for cadmium removal.

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Background and purpose: Lead is a toxic heavy metal that is considered major environmental contaminants and all its compounds are important in terms of toxicity in humans. So, the aim of this study was to _____the efficiency survey of pumice powder to lead removal from the aquatic environment. Material and Methods: In the beginning of this study, the powdered form of pumice was prepared, then the batch experiments were performed at room temperature in the variety of conditions including different contact times, various adsorbent dosages, pH=7, agitation periods=200 rpm and concentration of lead (50 mg/L). Obtained data were fitted to Langmuir and Freundlich isotherms and the pseudo first and second order and the intraparticle diffusion reaction kinetics. Results: The results showed that lead is most absorbed so its maximum removal was obtained 100%, Correlation coefficients indicate the following order to fit both isotherms: Freundlich and Langmuir for lead (R2=0.995, R2=9) respectively and second-order reaction kinetics. Also, the removal efficiency has significant difference by increasing the adsorbent dose and contact time (R2 >‍‍0.001). Conclusion: Note that the separation coefficient (RL) and adsorption intensity was obtained in the favorable range 1-0, so the pumice is the effective adsorbent for lead removal from the aquatic environment.

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Background and purpose: Nickel is one of the heavy metals that originates from various industries such as plating and dyeing and leads to many environmental problems, thus, it is important to remove it. The aim of this study was to assess the photocatalytic process by silica and zirconia nanoparticles in nickel removal. Materials and methods: In this applied-fundamental study after construcring photoreactor, the performance of silica and zirconia nanoparticles in the removal of nickel were studied by changing variables such as the amount of nanoparticles (0.5-2.5 g/L), pH (3,7,11), nickel concentration and exposure time of UV (15-75 min). After assessing the synthetic wastewater (n=50) real wastewater (n=10) samples were evaluated according to the resultant optimum conditions. Nickel adsorption isotherm was determined. SPSS was used to analyze the data. Results: Nickel was removed completely under optimum condittions (pH= 11), 1g/L zirconia, 0.5g/L silica with exposure time of 30min and 5mg/L synthetic nickel. Removal efficiency of nickel in concentrations of 5, 10, 15, 20 and 25 mg/L at pH= 11 and 1g/L zirconia nanoparticles was 100, 91, 88, 87.5 and 84%, respectively and with 0.5g/L dose of silica nanoparticles was 100, 100, 90.90 and 87%, respectively. According to the coefficient of determination (R2), Freundlich isotherm for zirconia nanoparticle (R2= 0.883) and the Langmuir model for silica (R2= 0.949) were found to be more relevant. Conclusion: Increase in the amount of nanoparticles, UV exposure and pH increased the efficacy of photocatalytic process in nickel removal through production of hydroxyl radicals. Nickel concentration reduced the process efficiency due to inhibition of the reaction of holes (h+) and hydroxyl radicals. Efficiency of photocatalytic process in removal of nickel from a real wastewater due to the presence of other substances (cyanide and zinc) was far less compared to the synthetic solutions. According to nickel removal efficiency from real wastewater (49.6% and 56% by zirconia nanoparticles and silica, respectively) photocatalytic processes was able to remove about 50% nickel from actual wastewater.

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Background and purpose: The presence of phenol and its derivatives in water and wastewater are of major concern because of their toxicity and threat to human life and environment. The aim of this study was determination of the modified lemna minor and azolla in phenol adsorption. Materials and methods: In this emperical-lab study, the washed lemna minor and azolla was used as adsorbents. The effect of vatious parameters on adsorbents performance was investigated. The concentration of phenol was measured by high-performance liquid chromatography (HPLC). Also, data were fitted with variety isotherm and kinetic models. Results: The phenol adsorption rate increased by increasing of contact time and adsorbent dose in both adsorbents however, the phenol adsorption per each gram of adsorbents (qe) decreased. The adsorption efficieny increased by decreasing intial phenol concentration. With increasing of solution pH, removal efficiency decreased and optimum pH was 3. Adsorption isotherm data showed that the phenol sorption followed the Langmuir. Kinetics of sorption was well described by pseudo-second order model. Conclusion: The lemna minor and azolla can be used as effective and low-cost adsorbents to organic compounds removal from industrial effluents. Although due to adventages such as more plenty and higher ability in phenol removal, the azolla is the best adsorbnet.

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Background and purpose: Fluoride in drinking water can be either beneficial or detrimental to health depending on its concentration. Its high concentrations leads to dental and skeletal fluorosis and lesions of the endocrine glands, thyroid and liver. This paper describes the removal of fluoride from water using lemna minor. Material and methods: This research was a lab study. The lemna minor plants were collected and dried in the oven at 105 in 24 h and sieved in 18-30 mesh. The optimum values of pH, contact time and adsorbent dosage were determined and the different concentrations of fluoride were experimented in lab scale conditions for modified lemna minor. The fluoride concentration was measured in wavelength of 518 nm by spectrophotometer. Also, the found data of this research were fitted with Variety Isotherm and kinetic models. Results: The results showed that by increasing pH solution, removal efficiency decreased and optimum pH was 5. Increasing of contact time and adsorbent dose can lead to the increase of the removal efficiency.Adsorption isotherm data show that the fluoride sorption followed the Langmuir No 2. Fluoride sorption is better agreed with pseudo- second order of Kinetics model which was well described by pseudo- second order model. Conclusion: The result of the present work shows that lemna minor can be used as an effective and cheap adsorbent for fluoride removal.

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Background and purpose: Recently, using agricultural wastes as a biosorbent in removal of heavy metals has been concentrated. The aim of this study was evaluation of Canola residuals on removal of cadmium from aqueous solutions. Materials and methods: This experimental study was performed in laboratory scale in a batch system. The effect of parameters such as contact time (5, 10, 15, 30, 45, 60, and 120 minutes), pH (2, 4, 6, and 7), initiative concentration of cadmium (15, 30, and 60 mg/l) and adsorbent doses (0.2, 0.6,1 g/100 ml) was evaluated. The sampled solutions of cadmium with known concentrations in 100 ml were prepared in Erlen Mayer of 150 ml. The samples were analyzed by atomic absorption spectrometry PG-999 instrument in wavelength of 228 nm. The results were compared using the Langmuir and Freundlich isotherms and kinetic models. Results: Maximum removal of cadmium was 95% happened in primary five minutes. Optimum pH was 6. Adsorption ability of cadmium increased with increasing initiative concentration of cadmium and adsorbent dose. The adsorption isotherm obeyed Freundlich model and the adsorption kinetic followed pseudo-second-order reaction. Conclusion: Based on the results, Canola residues could be used as a low-cost and efficient biosorbent for treatment of wastewater with cadmium.

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Background and purpose: Continuous input of antibiotics to the environment causes many problems such as antibiotic resistance in pathogenic microorganisms. Therefore, researchers are aiming to find solutions to reduce antibiotics in hospital effluents and polluted waters. Amoxicillin is an antibiotic which is widely used to treat infections. Due to inappropriate use it enters the wastewater and finally the environment in almost unmetabolized form. This study was conducted to evaluate the performance of multi-walled carbon nanotubes for Amoxicillin removal from aqueous solutions. Materials and methods: In this study the efficacy of multi-walled carbon nanotubes for the removal of amoxicillin was investigated in a batch system considering pH (10-4), ionic strength (0 to 0.1 mol/ L sodium chloride), and adsorbent dose (0.4 – 1.8 g /L). Finally, isotherms and kinetics of the adsorption was analyzed. Results: The results showed that the maximum removal of amoxicillin occurred at pH 8. Also, increase in the ionic strength decreased the removal efficiency while increase in the adsorbent dose increased the removal efficiency. The equilibrium adsorption isotherm data well fitted with Langmuir model (R2= 0.9108) and adsorption kinetics fitted with pseudo second order model. Conclusion: According to the results multi-wall carbon nanotubes could be assumed as an acceptable adsorbent for Amoxicillin removal in the aquatic solutions.

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Background and purpose: Dyes are one of the most contaminants in textile industrial wastewater that are often carcinogenic, mutagenic and non-degradable. Therefore, their removal from effluents is very essential to avoid environmental consequences. The purpose of this study was to gain a better insight into the adsorption process and using an economic technology for dye waste water treatment. For these purposes activated carbon was used. Materials and methods: In this study, the adsorbent surface properties were evaluated using converted Fourierinfera red (FT-IR) test and scanning electronic microscope (SEM). In discontinuous station, adsorbent effectiveness for methylene blue dye removal was measured considering pH, reaction time, adsorbent dose, initial dye concentration and temperature. Finally, data was analyzed using seven kinetic and four isotherm models. Results: The highest removal efficiency of methylene blue was obtained at pH=6, reaction time=180 minutes, and adsorbent dose=2 gl-1. Removal efficiency of methylene blue in initial concentration (50 mg-1) was 91.08%. In this study the adsorption process followed the Langmuir isotherm (R2= 0.9971). Also, kinetic studies showed high correlation coefficient on pseudo-second order equation ((R2= 0.996). Conclusion: According to this study, activated carbon from Oak fruit bark could be used as an effective and economic adsorbent in wastewater treatments.

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Abstract Background and purpose: Phenols are considered as priority pollutants because of their potential harm to human health. So, they should be removed from water resources to avoid further pollutions. The aim of this research was to evaluate phenol adsorption from aqueous solution using activated carbon provided from Populus alba. Materials and methods: In this experimental study we used activated carbon as adsorbent with a mesh 40 that was provided from P. alba. After preparation of stock solution, the effect of influencing parameters on adsorption process such as pH (4, 6, 8, 10), contact time (3-60 min), adsorbent dosage (0.25-5g/l), and initial phenol concentration (10-50 mg/L) were evaluated. Also, to describe the experimental data, the Langmuir, Freundlich, and Temkin isotherms, pseudo first- and pseudo second- order kinetic models were assessed. All experiments were conducted twice and the mean of percentage removal was obtained. Results: BET surface areas of the activated carbon provided from P. alba were obtained at 1068 m2/g. According to Langmuir model, the maximum adsorption capacity of 172.41 mg/g was attained. Kinetic evaluation indicated that the adsorption of phenol by the investigated activated carbon followed the pseudo-second order reaction. This study showed that increase in contact time and adsorbent dosage increased the adsorption of phenol. While increase in pH and initial phenol concentration decreased phenol adsorption. Phenol was completely removed at pH4. Conclusion: The activated carbon provided from P. alba was found with a good potential for phenol removal from wastewaters. P. alba tree is abundantly found in many areas in Iran, therefore, it could be used to produce adsorbent and may be applied for removal of pollutants in water and wastewater industry.

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Background and purpose: Phenol and its derivatives are used as raw material in many chemical, pharmaceutical and petrochemical industries. It is classified as priority pollutant, due to its high toxicity. In this study, the magnetic activated carbon nano-composite was used for quick removal of phenol. Materials and methods: The activated carbon was modified by magnetic nano-particles. Then physical properties of the adsorbent were investigated using BET, XRD and SEM. Afterwards, adsorption behavior of phenol onto the adsorbent was studied considering various parameters such as: pH, phenol concentration, contact time and adsorbent dosage. Also, the isotherms and adsorption kinetics model was studied. Results: BET analysis showed 10.25% decrease in the specific area of activated carbon after being amended by the Fe3O4 nano-particles. SEM and XRD confirmed the presence of Fe3O4 nano-particles on the activated carbon. Optimum absorption points in this process were pH=8, contact time of 15 min and adsorbent dose 2g/L. The Longmuir isotherm and pseudo-second-order kinetics were fitted to the data. The maximum adsorption capacity of phenol on AC_Fe3O4 was 84.033 mg/g. Conclusion: Creating magnetic properties on the activated carbon which has a high adsorption capacity of phenol could result in quick separation of phenol from aqueous solutions. Also, this adsorbent could be widely applied since it is inexpensive and simple to use.

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Background and purpose: Dexamethasone is one of the most commonly used Glucocorticoids (antibiotics) in medical centers. Conventional treatment methods for removal of Glucocorticoids from wastewaters are not highly efficient, therefore, more effective methods are needed to reduce the entry of these compounds into the environment. The aim of this study was to evaluate the performance of Clinoptilolite zeolite (Cp) in removal of dexamethasone from aqueous solutions, and introducing a suitable isotherm for modeling of the adsorption process.

Materials and methods: In this study, the effect of some parameters including pH of the solution (4, 7 and 9), adsorbent dose (0.2, 0.6 and 1 gr), and contact time (15, 30, 45, 60, 90 and 120 min) were studied on adsorption capacity of Cp. The initial concentration of 5 mgr/l was considered. The isotherm of adsorption process was studied using Langmuir and Freundlich isotherms. The concentration of dexamethasone was measured by UV-visible spectrophotometer. SEM photographs were taken from adsorbent before and after the adsorption process.

Results: The results showed that the maximum adsorption capacity was 1.13 mg/g which was obtained in pH=4, using 0.2 gr adsorbent during 90 min. By increasing the amount of adsorbent, the removal efficiency increased, but adsorption capacity decreased. The specific surface and pores volume of zeolite were 43.91cm²/gr and 0.1717cm³/gr, respectively. The Langmuir model fitted well to the experimental data (R²=0.99).

Conclusion: In this study, Clinoptilolite zeolite was found to be very suitable in removal of dexamethasone from aqueous solutions.

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Background and purpose: Adsorption is considered as one of the promising treatment methods for removal of heavy metals from aqueous solutions. The aim of this study was to determine the efficiency of Padina sanctae crucis in removal of manganese (Mn) from aqueous solutions.

Materials and methods: Biosorption was studied in a series of batch experiments at room temperature and the effects of experimental parameters such as biosorbent dose (0.1-10 g/L), contact time (3–120 min), pH (3, 5, 7, 8) and initial Mn concentration (0.5–100 mg/L) were studied.

Results: The highest removal biosorption of Mn was reached at 5 g/L biosorbent dose, 20 min contact time, and 20 mg/L initial Mn concentration (100% removal). Langmuir model was better fitted than Freundlich model that showed homogeneous biosorption surface and the possibility of monolayer biosorption of Mn by biosorbent. The biosorption kinetics was controlled by the pseudo-second order.

Conclusion: According to the results, Padina sanctae crucis could be used as an effective and low-cost biosorbent for Mn removal from aqueous solutions.

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Background and purpose: The aim of this study was to investigate the efficiency of Fe₃O₄ nanoparticles synthesized by the chemical co-precipitation method for removal of black acid 1 from aquatic solutions.

Materials and methods: In an experimental study, the Fe₃O₄ nanoparticle was synthesized by the chemical co-precipitation method using Fe⁺² and Fe⁺³ solution in the presence of N₂. The effect of different parameters including initial pH, adsorbent dose, contact time, initial dye concentration, temperature, and EC and also intervening variables such as nitrate, sulfate, fluoride, chloride and hardness were investigated. In addition, equilibrium data was fitted into Langmuir and Freundlich isotherm model, and pseudo-second order and pseudo-first order kinetic models.

Results: We found that the adsorption capacities of nanoparticle increased when pH and adsorbent dose decreased. But the removal efficiency decreased by increase in temperature and dye concentration. Also intervening variables (nitrate, sulfate, fluoride, chloride, and hardness) were found to have low effect on decreasing the color absorption capacity by Fe3O4 nanoparticles. The removal of dye using Fe₃O₄ nanoparticle complies with Freundlich isotherm model (R²= 0.991). Also, the equilibrium adsorption data fitted with pseudo-second order kinetic (R²= 0.992).

Conclusion: This study showed that the Fe3O4 nanoparticle is highly capable of removing black acid 1 dye from aqueous solutions in low contact time. Therefore, the Fe3O4 nanoparticle can be considered as an effective adsorbent in dye removal.

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Background and purpose: Fasciola hepatica and Fasciola gigantica are common liver flukes which affect both human and livestock worldwide. In this study we evaluated the loop-mediated isothermal amplification (LAMP) assay for detection and discrimination of Fasciola species.

Materials and methods: Fifty adults of Fasciola worms were isolated from sheep and cattle liver form abattoirs in Mazandaran province. A total of 8 primer sets for LAMP was designed to amplify the 28S ribosomal RNA gene of Fasciola sp. Conventional LAMP was carried out in a 20µI reaction mixture under isothermal condition at 60°C for 90 minutes. Amplification result was observed by monitoring the turbidity by naked-eye, using fluorescent dye and gel electrophoresis. The specificity of LAMP method for detecting Fasciola sp. was tested by amplification of Dicrocoelium dendriticum, Trichostrongylus colubriformis, and Echinococcus granulosus DNA templates. To evaluate the detection limit of LAMP assay in detecting Fasciola genus, serial dilution of the extracted DNA was used.

Results: A positive LAMP reaction by the specific primers of two species produced many bands of different sizes in 60^0C after 90 min. The optimal assay conditions were established with no reaction with other parasites’ DNA. The detection limit of this LAMP assay was 1 pg DNA/tube. The result of turbidity and fluorescent dye detection were consistent with agarose gel electrophoresis.

Conclusion: Our results demonstrated that LAMP is a rapid, cost-effective, highly specific, easy, and reliable method for differentiation of Fasciola sp. in epidemiological and clinical researches on human and domestic animals in endemic regions of fasciolosis.

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Background and purpose: Dyes in textile wastewater are amongst the main sources of environmental pollutants that are harmful for environment and human health. This study was designed for experimental evaluation of Reactive Blue 19 absorption from aqueous solutions by dried powder, modified powder, and modified carbon derived from Azolla aquatic plant carbon filiculoides, as a low cost adsorbent.

Materials and methods: In this experimental laboratorial study the effects of various parameters (initial dye concentration, contact time, pH and, amount of adsorbent (on the dye removal efficiency was investigated. Then the isotherm, kinetic, and thermodynamic equations were done. Measuring the amount of dye concentration was determined using a spectrophotometer at a wavelength of nm 594. Adsorbent characteristics were analyzed using SEM, FTIR, and BET techniques. Statistical analysis was done by Excel software.

Results: The highest absorption capacity were 4.83 mg/g by modified powder, 4.55 mg/g by dried powder, and 4.15 mg/g by modified carbon which were observed in optimum conditions: pH=2, equilibrium time of 60 min, 10 g/L of adsorbent, and initial dye concentration of 5 mg/l. The absorption efficiency of Azolla filiculoides increased by increasing the adsorbent dose and contact time, and decreasing the initial concentration of dye. It was found that the adsorption process followed Lungmuir isotherm and the kinetic model of pseudo second-order. The maximum absorbance of dye occurred by modified powder of Azolla filiculoides.

Conclusion: According to our results, adsorption process by Azolla aquatic plant is an efficient and affordable method for removal of dyes from textile industry wastewater.

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Background and purpose: Textile industries play a vital role in the economy of any country, and the management of their effluent is crucial for environmental sustainability. The use of various dyes during the production process results in highly colored wastewater that requires treatment before discharging into the environment. Thus, the objective of this study was to assess the effectiveness of the adsorption process as one of the best and simplest methods for the removal of Acid Red 18 (AR-18) dye from aqueous environments.
Materials and methods: In this experimental study, we focused on the synthesis and characterization of magnesium oxide (MgO) nanoparticles. Then, the efficiency of this adsorbent was investigated for the adsorption of AR-18 dye from aqueous solutions, and then its removal efficiency was compared with powdered activated carbon (PAC). The research involved evaluating the impacts of various variables such as solution pH, adsorbent dosage, contact time, and initial dye concentration on the adsorption process. Non-linear analysis using OriginPro 18 software was used to model adsorption kinetics and isotherms data.
Results: The results of the study indicated that the solution pH had a negligible impact on the removal of AR-18 dye within the investigated concentration range. However, for PAC adsorbent, increasing the contact time and adsorbent dosage resulted in higher removal efficiency of the dye, and equilibrium was reached after 120 minutes. The general order kinetic model and Liu isotherm model well described the experimental data.
Conclusion: Based on the results of the study, it was found that magnesium oxide (MgO) nanoparticles were not effective as an adsorbent for the removal of AR-18 dye and exhibited low adsorption efficiency. On the other hand, powdered activated carbon (PAC) demonstrated a significantly higher adsorption efficiency and can be considered as an effective adsorbent for the removal of AR-18 dye from aqueous solutions.