جستجوی مقالات مرتبط با کلیدواژه « جذب سطحی » در نشریات گروه « علوم پایه »

In this research, graphene oxide-silver (GO-Ag) nanocomposites (NCs) was prepared using tamarindus indica extract (green reducer). These NCs was characterized by conventional methods such as Fourier Transform Infrared Spectroscopy (FT-IR), X-ray Diffraction Pattern (XRD), Scanning Electron Microscopy (FE-SEM), X-ray Energy Diffraction Spectroscopy (EDS), Raman spectroscopy and TGA thermal analysis. The as-prepared NCs was used as an absorbent in the process of removing lead ions from aqueous solution. The surface absorption process of lead ions by GO-Ag NCs and the factors affecting this absorption process: such as the concentration and pH of the lead solution, the amount of adsorbent (GO-Ag) used, the contact time of the adsorbent with the solution and the temperature of the absorption process were investigated. The removal percentage of lead ions and adsorption capacity were 97.70 % and 152.60 mg/g for 50.0 mL of lead(II) solution 125.0 ppm and pH = 5.0 in the presence of 0.040 g of GO-Ag (2:1) with a contact time of 7 minutes, respectively. On the other hand, experimental evidence showed that the surface adsorption process of lead(II) ion on GO-Ag substrate follows pseudo-second order kinetics and the Langmuir adsorption isotherm model can be considered for it.

Nowadays, supramolecular hydrogels as a new type of three-dimensional compounds based on non-covalent interactions have attracted the attention of many scientists of different sciences due to their diverse and easy preparation methods and unique characteristics compared to their covalent counterparts. Therefore, in the present research, green cellulose nanoparticles was prepared from cotton by acid hydrolysis process and then separately functionalized with citric acid and pyridine pendant groups in order to create anionic and cationic components. Next, supramolecular hydrogels were prepared through electrostatic interactions between the mentioned components. The successful preparation of hydrogel was investigated using Fourier transform infrared spectroscopy, SEM and X-ray diffraction. Study of the morphology of the hydrogel showed a porous structure containing holes of different sizes. Also, the investigation of the crystal structure of the hydrogel showed its high crystallinity. Finally, the removal of methylene blue cationic dye from industrial wastewater was investigated through the absorption process and using the prepared hydrogel as an adsorbent. Also, the effect of methylene blue initial concentration and contact time at room temperature on the absorption process was investigated. The study of absorption kinetics showed that the absorption process follows the second-order absorption kinetics. The maximum absorption capacity obtained for this adsorbent was 97 mg/g. The present study showed that the prepared supramolecular hydrogel, in addition to features such as biocompatibility, avalability, and simple and fast preparation, has a good potential for methylene blue absorption.

In this study, processed chicory leaf powder was used as a natural adsorbent to remove cobalt ions from aqueous media. Natural adsorbents were characterization by several methods include X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform spectroscopy (FTIR), Brunauer-Emmet-Teller (BET) and Particle size analyzer (PSA). A set of experiments was performed to detect the optimal conditions and to investigate the effects of various parameters such as initial concentration, contact time, adsorbent dose, solution pH and temperature on the percentage of removal. The optimal conditions for cobalt removal were: pH = 6-8, contact time 20 min, adsorbent dose 20 mg and initial concentration 15 (mg L-1). Adsorption data showed that the adsorption process is more compatible with Langmuir's isotherm. The kinetic data were consistent with the quasi-second-order model with a valid correlation coefficient. Calculation of thermodynamic values ​​showed that the adsorption process is spontaneous, with decreasing entropy and exothermic. Finally, the introduced sorbent was compared with a strong adsorbent such as carbon nanotubes doped with silver nanoparticles (Ag2O-MWCNT). The optimal conditions for the removal of cobalt ions by the processed synthetic adsorbent were: initial concentration of 10 mg L-1, contact time of 40 min, amount of adsorbent 30 mg and pH = 7. Adsorption data showed that the adsorption process for cobalt ions is compatible with Freundlich's isotherm. The kinetic data were consistent with the quasi-second-order model with a valid correlation coefficient. Calculation of thermodynamic values ​​showed that the adsorption process was spontaneous and exothermic. The results of this comparison show that the introduced natural adsorbent performs even better than the synthetic and expensive adsorbent and provides a promising outlook if further processing and modifications are performed on this adsorbent.

In this study, 3-Picrylamino-1,2,4-triazole interaction with carbon nanocone dots was evaluated by infrared (IR), natural bond orbital (NBO) and frontier molecular orbital (FMO) computations. The negative values of adsorption energy, enthalpy changes, Gibbs free energy variations showed 3-Picrylamino-1,2,4-triazole adsorption on the surface of carbon nanocone is exothermic, spontaneous and experimentally feasible. Structural parameters including the energy of HOMO and LUMO orbitals, bandgap, electrophilicity, chemical potential, chemical hardness, density and zero-point energy were also calculated and discussed. The remarkable decrease in bandgap after the 3-Picrylamino-1,2,4-triazole adsorption on the surface of carbon nanocone demonstrated that the electrochemical conductivity and electrocatalytic properties increased after adsorbate interaction with the adsorbent and carbon nanocone can be used for construction of new electrochemical sensor in order to 3-Picrylamino-1,2,4-triazole detection and quantitation. In addition, this phenomenon showed 3-Picrylamino-1,2,4-triazole complexes with carbon nanocone can be a more powerful energetic substance than the pure 3-Picrylamino-1,2,4-triazole molecule without the nanostructure.

This study includes the development of a new nanosorbent for the treatment of dye effluents. The designed and fabricated nanosorbent is comprised of a dendritic structure with symmetric primary amine active sites and a magnetic core. Employing various characterization techniques such as NMR, SEM, TEM, TGA, zeta potential, and CHN elemental analysis, the adsorption capacity of this material to remove methyl-orange dye has been investigated. The results reveal that the proposed nanosorbent offers an efficiency of approximately 68.9% with an adsorption rate of 166.2 g/min in the methyl-orange removal process. The rate constant obtained for methyl-orange adsorption on the nanodendrimer is higher than the previously reported ones, indicating a higher adsorption rate. The results of this new nanosorbent prove its high potential in adsorptive methyl-orange removal.

The aim of this study was to model the removal efficiency of cefixime by the Fenton method using a neural network. This model predicts experimental results well. In this model, the amount of hydrogen peroxide, iron catalyst, cefixime removal time, initial concentration of cefixime, and pH are the input parameters. The output variable is the removal percentage of cefixime. Total error squares (SSE), mean the square root of error (RMSE), adjusted coefficient of determination (), and coefficient of determination   in determining the number of optimal neurons in the middle of the performance index. According to the obtained results, the neural network model was able to predict the absorption efficiency with the sigmoid tangent transfer function in the hidden layer and the linear stimulus transfer function in the output layer. Also, the results of modeling the neural network with org-art showed that the grid with a 1-13-5 arrangement (5 neurons in the input layer, 13 neurons in the hidden layer, and 1 neuron in the output layer) had the best result in predicting the output. The correlation coefficients of all the levels of training, validation, and test 0.3 were 0.99436, 0.9993, and 0.96901, respectively. To predict the trend of changes, neural network tools have been used in MATLAB software.

The asphaltene present in crude oil creates various challenges for its production, processing, and transportation, with the most important ones being wellbore and pipeline fouling, deactivation, and poisoning of catalysts. In this study, the adsorption of asphaltene extracted from a crude oil sample on five iron oxide nanoparticles synthesized by the Pechini method, in the presence and absence of propylene oxide and polyethylene glycol as common agents used in the sol-gel method for gel formation, was investigated. Solutions with different percentages of asphaltene and toluene were prepared, and a specific amount of iron nanoparticles (4 g/l) was added to the solutions. The mixtures were shaken for 15 hours at 250 rpm. The unknown concentration of the samples was determined by UV-visible analysis. The results indicated that the iron oxide synthesized without propylene oxide and polyethylene glycol, with an adsorption capacity of 37.31%, exhibited the best performance in asphaltene adsorption and was economically more viable. The adsorption results were described using Langmuir and Freundlich isotherms, and the physical properties of the nanoparticles were determined by XRD and BET analyses.

In this research, the adsorption of nickel ions in the batch system by orange peel carbon has been investigated and the effect of factors such as pH, contact time, initial concentration of nickel in solution, adsorbent amount, and the temperature has been considered. The surface details and functional groups were investigated by SEM and FTIR analyzes, respectively. In the study of the effect of pH, the highest percentage of nickel uptake for orange peel carbon occurred at pH = 6, which is equivalent to 58 mg/g. With increasing the contact time between the adsorbent and the solution and after 210 minutes, the adsorption percentage increased to 98.57%. In the study of the effect of the initial concentration of nickel in the range of 20 to  150 mg/L, the results showed that with increasing concentration, the percentage of adsorption decreased from 98% to 96%, and with increasing the amount of adsorbent from 0.01 to 0.1 g per 25 ml. Nickel solution, the adsorption percentage increased from 90% to 98%. The effect of temperature showed that with increasing the temperature from 25 to 45°C, the percentage of adsorption decreased from 99% to 97.8%. Thermodynamic properties were studied at three temperatures of 25, 35, and 45°C. The negative free energy value of the standard Gibbs (∆ Go) which is equivalent to -121.3 kJ / mol, indicates that the adsorption process is spontaneous and physical. In the kinetic study of the contact time effect, it was observed that the results fit well with the second-order kinetic model with a correlation coefficient of 99%. In investigating the effect of the initial concentration of nickel in solution and fitting experimental data with Langmuir, Freundlich, Temkin, Dubin Radushkovich isotherms, and according to the values ​​obtained at R2, Freundlich's isotherm had the highest compatibility with 100% correlation coefficient.

Emerging pollutants from water are a significant concern in modern society, and surface adsorption has been identified as a promising method to eliminate them. Preparation of an effective adsorbent is crucial for the adsorption method. In this study, a new adsorbent of Metal organic frameworks, MIL-101(Cr)@ZnO, was synthesized by modifying MIL 101(Cr) with zinc oxide nanoparticles using the hydrothermal method. The adsorbent was characterized using XRD, FTIR, FESEM, EDX and BET analysis. The adsorbent's efficiency was evaluated by studies of adsorption equilibrium isotherms under optimal conditions pH = 9, amount of adsorbent 0.0035 g, volume 50 ml, time 60 minutes, at different temperatures (60, 40, 35 °C) and concentrations of methylene blue (6, 8, 9, 10, 11 mg/L). The equilibrium adsorption data were analyzed using Langmuir, Freundlich, Temkin, Alovich, and Dubinin-Radoshkevich(DR) two-parameter equilibrium isotherms models. The obtained results showed that the order of dye adsorption of the studied isotherms is as follows: Dubinin-Radoshkevich>Temkin>Freundlich>Alovich>Langmuir. Additionally, the order showed that the adsorption of methylene blue occurs in a multilayered form. The isotherm of Dubinin-Radoshkevich with the highest correlation coefficient (R2=0.9767) and low average free energy (E=0.975 J/mol) showed that physical adsorption is the dominant process of adsorption. The maximum adsorption capacity of Langmuir isotherm was determined at the temperature of 313 K with the value of qmax=258.7143 mg/g, the separation factor at the same temperature (RL=0.4364) indicating favorable adsorption. The Freundlich adsorption intensity and correlation coefficient values were n=1.3825 and R2=0.879, respectively. The heat of adsorption in the Temkin's model was calculated to be BT=57.192 J/mol, and the highest adsorption capacity was obtained from Elovich's isotherm qmax=333.3333 mg/g. Further, the amount of thermodynamic values showed that the adsorption process of the pollutant is a spontaneous and endothermic process. The present study's evidence indicates that the adsorption of methylene blue follows a physical process.

In recent years, research on the widespread use of biodegradable polymers, such as sodium alginate (SA), in removing pollutants from water sources has shown significant growth. The present study aims to evaluate the efficiency of SA hydrogels cross-linked with ferric chloride (for mechanical strength) in optimizing the removal of nickel (Ni) from aqueous solutions. Various factors, including Ni initial concentration, solution pH, amount of adsorbent, and contact time, were considered using response surface methodology (Box-Benken model). Based on the results of FTIR and SEM analyses, activated SA hydrogels were found to have hydroxyl and carboxyl functional groups, and their surface morphology was non-flat and prominent. The Ni removal values in the presence of SA hydrogels varied, with the minimum and maximum removal percentages being 53.39% and 85.43%, respectively. Increasing the initial Ni concentration resulted in a decreasing trend in Ni removal, while increasing contact time, solution pH, and amount of adsorbent led to an increasing trend in Ni removal. The evaluation of the data obtained from Ni removal using the Box-Benken model showed an accurate prediction (R2 higher than 0.98%) in optimizing Ni removal from aqueous solutions in the presence of SA. The possible mechanisms of Ni removal by SA hydrogel were identified as the formation of Van der waals bonds (physical adsorption), interaction with carboxylate anions, chelate formation between Ni ions and hydroxyl functional groups, and electrostatic interactions (due to the negative surface charge of SA). Overall, the results of this study demonstrate that SA has a suitable ability to remove Ni from aqueous solutions. However, future studies should investigate, compare, and integrate other activation methods, such as physical activation (combination with inorganic substances) and chemical activation (surface grafting) on the SA polymer, to improve the removal efficiency of heavy elements using this polymer.

In this study, montmorillonite modified by the hexadecyltrimethylammonium bromide (HDTMA-Br) was prepared by the reaction of the sodium montmorillonite with HDTMA-Br surfactant. The adsorbent structure was characterized using Fourier transform infrared (FT-IR), thermogravimetric analysis (TGA), power-spectral-density (PSD), Brunauer-Emmett-Teller (BET), X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM) techniques. Then, the efficiency of synthetized adsorbent was investigated for the removal of the chemical oxygen demand reduction (COD), biological oxygen demand (BOD), suspended solids (TSS), oil and grease and turbidity of the oilfield produced water. The exchange capasity was obtained 200 % for modified montmorillonite. The maximom of COD reduction was resulted 92.04 % at optimal conditions with the adsorbent dosage 0.3 g, pH = 7, and contact time 45 min. The advantages of this method are cheapness, safety, and reusability of the adsorbent, short time treatment, high adsorption capacity, easy separation of the adsorbent from the reaction medium.

Cyanide is one of the toxins and different ways to reduce it have been studied. These include ozone oxidation methods, ultraviolet radiation degradation, alkaline chlorination, and hydrogen peroxide degradation. Each of these methods has various disadvantages and advantages, but among them, surface adsorption is an effective and efficient method. On the other hand, zeolites, which are crystalline aluminosilicate and juicy alkali and alkaline earth metals, have the ability to absorb cations and anions. To prepare a cyanide solution, it was used sodium cyanide salt based on the standard method In this work, it has been studied the adsorption of cyanide ion from aqueous solutions using zeolite nanoparticles and the factors affecting on it. In this study, the factors of the effect of the initial pH of the solution, the effect of the initial concentration of the solution, the effect of the adsorbent amount, the effect of the contact time and the effect of temperature on the surface adsorption of cyanide ions with the nano-adsorbent zeolite clinoptilolite were investigated. And after the studies, the optimal and appropriate values for each of the effective parameters pH=6, contact time 40 min, adsorbent dosage 1g/l, temperature 22°C and initial concentration of 150 mg/l. Under these optimal conditions, the highest percentage of anion cyanide uptake was obtained on the nano-adsorbent of zeolite clinoptilolite 85%. The relationship between empirical data and the equation of Langmuir, Freundlich and Tamkin equations was also investigated. The R2 values for Langmuir, Frondelich, and Temkin's alliances were 0.8337, 0.9837, and 0.99, respectively, indicating that there was a greater match between the experimental data and the Temkin temperature than the other two.

In this paper, nanocrystals of zeolitic imidazolate frameworks (ZIF-8) were synthesized by solvothermal synthesis method, and their modification was conducted using molybdenum (Mo) promoter. The aforementioned modifications were carried out by two methods, including loading of Mo in ZIF-8 structure and also impregnation of ZIF-8 with Mo. Adsorption isotherms of CO2 and CH4 were determined according to the pressure decay method in the temperature and pressure ranges of 298-328 K and 1-4 bar, respectively. The obtained results indicate that presence of Mo promoter causes obvious changes in structural properties of the ZIF-8 nanocrystals, such as surface area, pores volumes, as well as, adsorption properties. Moreover, CO2 adsorption of the modified nanocrystals was obtained less than that of the parent ZIF-8. On the other hand, CO2/CH4 selectivity value of the modified ZIF-8 nanocrystals by impregnation has increased by 85% compared to non-modified ZIF-8.

In the presented method, modified magnetic nickel oxide was synthesized and identified for pre-concentration and determination of gemfibrozil in human serum samples, pharmaceutical wastewater and drug. Fourier transform infrared spectrum (FTIR), X-ray diffraction (XRD) and scanning electron microscope (SEM) were used to identify magnetic nickel oxide nanoparticles. Some parameters affecting the extraction, including pH effect, amount and type of elution solvent, extraction time, etc., were optimized and investigated. The concentration factor was 120, the limit of detection (LOD) was 0.16 µg.L-1, and the linear range of the calibration curve was 0.05 to 10 µg.L-1. The adsorption capacity was 52.69 mg.g-1. This method was successfully used to determination of gemfibrozile in human serum samples, pharmaceutical wastewater and drug using UV-Vis spectrometer with recovery in the range of 0.98-0.104%. Then, the samples determined by the proposed method with the results of the standard high-performance liquid chromatography (HPLC) method were compared. The results were checked with T-test and showed that there is no significant difference between the two methods.

In this study, the performance of fullerene (C20) as an adsorbent and sensor for the removal and detection of cefalexin was scrutinized by density functional theory computations. The negative values of adsorption energies showed cefalexin interaction with the nanostructure is experimentally possible. The negative values of enthalpy changes and Gibbs free energy variations demonstrated cefalexin adsorption on the surfaces of the adsorbent is exothermic and spontaneous. The values of thermodynamic constants indicated cefalexin interaction with C20 is reversible, equilibrium and two-sided. The NBO results showed cefalexin adsorption on the pristine fullerene is a physisorption because of non-formation of chemical bonds. The influence of temperature on the adsorption process was inspected and the obtained results showed cefalexin interaction with the nanostructure is more favorable at lower temperatures. The computed DOS spectrums showed the bandgap of C20 experienced a +296.9% decline from 1.950 (eV) to 7.750 (eV). Hence, this nanostructure can be employed as a sensing material for the development of new electrochemical sensors for the detection of cefalexin.

In this study, amoxicillin from aqueous solutions was adsorbed by activated carbons from eucalyptus leave and wheat straw through adsorption process. The effects of varying parameters such as initial pH of amoxicillin solution, initial concentration of amoxicillin solution, adsorbent dosage, contact time and temperature on the adsorption process were examined. Under optimum conditions containing pH 11, amoxicillin initial concentration 10 mgL-1, adsorbent dosage 0.07 g, contact time 30 and 60 min for eucalyptus leave and wheat straw, respectively, and temperature 25±1oC, maximum adsorption percentages for amoxicillin on eucalyptus leave and wheat straw were obtained 72.4% and 79.2% respectively. In addition, comparison of the experimental results with Langmuir, Freundlich and Temkin adsorption isotherms, showed that the Langmuir isotherm have better fitting with the equilibrium data than the Freundlich isotherm but the fitting with Temkin isotherm is weaker for both adsorbents. Also, thermodynamic parameters of the adsorption such as 〖∆H〗^0 and 〖∆S〗^0 were calculated that theirs negative values showed that the amoxicillin adsorption on eucalyptus leave and wheat straw is an exothermic process and along with decrease of randomness, respectively. Meanwhile, the more negative value of 〖∆G〗^0 at 25oC compared to higher temperatures is a sign of more spontaneous adsorption process at this temperature. In addition, the study of adsorption kinetics showed that the amoxicillin adsorption on both adsorbents is pseudo-second order.

 Landfill leachate is a highly toxic and hazardous form of wastewater due to its complex composition characteristics. Effective removal of heavy metals from landfill leachate is of great concern due to the fact that toxic metals can seriously threaten the food chain, and therefore the human health. The main objective of this work was to study the utilizing of low-cost pruning residues in the production of biochar and its application in removal of lead (Pb) from landfill leachate.

 Leachate produced in Babol municipal solid waste landfill was used as an adsorbent solution. Pruning residues were collected and used for biochar preparation. Biochar produced under the pyrolytic temperature of 700°C with a 1-hour retention time. The adsorption mechanism of pruning waste biochar to Pb was analyzed through BET surface area and scanning electron microscope (SEM) tests. Batch experiments were performed to study the effects of adsorption parameters on Pb removal. The influence of contact time (30-300 min), adsorbent dosage (1-50 g/L), as well as particle size (1-2 mm and 63-75 µm) was investigated. Moreover, the kinetic and isotherm models were applied to the experimental data to predict the adsorption parameters.

 The results obtained from the analysis of the untreated Babol landfill leachate was revealed that the Pb concentration was about 4.94 mg L-1. The surface area of the produced biochar was determined to be 292.44 m2 g-1. SEM microstructure of the biochar showed the developed surface area with visible pores. All of these data seem to suggest a great potential for pruning residues biochar to Pb removal. The adsorption of Pb was mainly affected by contact time, adsorbent dose, and biochar particle size. Higher contact time and adsorbent dosage showed higher uptake of Pb. Whereas, the uptake of Pb ions onto pruning residues biochar was substantially reduced with increase the biochar particle size. Maximum Pb percentage removal was observed at a contact time of 90 min and with an optimum biochar dosage of 20 g L-1 (89.06% removal) for biochar with 1-2 mm particle size. While, biochar with particle size of 64-75 µm can removed Pb to almost 100% at a contact time of 120 min and with an optimum biochar dosage of 20 g L-1. The kinetic study showed that adsorption can be well described by the pseudo-second order kinetic model. This supports the chemisorption theory behind the pseudo-second order kinetic model for the adsorption system. The results of isotherm models implied that the behaviors of the isotherms are more appropriate for the Langmuir model, showing a monolayer adsorption capacity for Pb.

 Findings of this research demonstrated the applicabil ity of pruning residues biochar as an economic adsorbent for the removal of the Pb from landfill leachate. On the other hand, the crop residue burning poses a threat to the environment and human health due to the emission of toxic gasses and particulate matter. So, conversion of pruning residues to biochar and its application to heavy metal removal is a useful and environment-friendly alternative to crop residue and biomass burning.

Various pollutants such as dyes following the arrival to ecosystems lead to serious global environmental pollution. Due to global strict regulations, it is obligatory to treat the wastewaters before being discharged into the environment. One of the common, reliable and useful techniques employed for removal of synthetic dyes from industrial effluents is an adsorption process. In this study, the adsorption of crystal violet (CV) was carried out from aqueous solution PCN-224/Sepiolite composite obtained from meso-tetrakis (4-carboxyphenyl) porphyrin (TCPP) with different experimental conditions was investigated. The composition and structure of compounds were characterized by FESEM and XRD methods. The effect of various variables including dye concentration, adsorbent amount and contact time was investigated by batch method. Equilibrium data were evaluated using Langmuir, Friendlich and Tamkin isotherms. The Langmuir model best describes the CV dye adsorption, which shows that the CV dye adsorption on PCN-224/Sepiolite composite is monolayer and homogeneous. The maximum adsorption capacity under optimal conditions (adsorbent: 0.02 g, contact time: 120 min, temperature: 25°C) was 38.17 mg g-1. Kinetic data were analyzed using first-order and second-order equations. The quasi-second-order model showed the best fit for the synthetic studies (R2=0.9985), which indicates that CV adsorption is limited by the chemical adsorption process. Overall, the results show that PCN-224/Sepiolite composite can be used as an efficient adsorbent for the treatment of colored effluents.

In this study, the multi-walled carbonnanotubes (MWCNTs) were functionalized and then were characterized by the several techniques such as :Fourier-transform infrared spectroscopy analysis, X-ray powder diffraction ,scanning electron microscopy, Brunauer-Emmett-Teller and Barett-Joyner-Halenda analysis and particle size analyzer. Then, the functionalized multi-walled  carbonnanotubes were used for removing Cr (III) ions from aqueous media. Several adsorption experiments were carried out for evaluating the adsorption capacity of the synthesized FMWCNTs. For adsorbing Cr (III) ions from aqueous solutions. The experimental results showed that the synthesized FMWCNTs have a good capacity for Cr (III) ions adsorption. The effect of the initial concentration of the sorbate, sorbent dosage, temperature, pH  and contact time on the removal  percentage of Cr ( III) ions on to the FMWCNTs and the adsorption capacity of the prepared adsorbent was studied and the optimum value of each of them was determined.Based on the experimental results, the isotherm models evaluation was also performed and the obtained results revealed that the Langmuir, Freundlich, Temkin and Dubinin-Radushkevich models can be used for interpretation the experimental results. Kinetic study showed that the kinetic results of this research can be compared with the pseudo first order, Elovich and intraparticle diffusion kinetic models and selecting ones with the largest R2. In addition, adsorption thermodynamic study ,on the basis of the adsorption capacity dependence on the  temperature,was performed. The obtained results showed that the considered adsorption process at the used temperature range is exergonic G0ad<0 and exothermic H0ad<0 and with a decrease in the randomness (S0ad< 0). Based on the magnitude of H0ad, one can claim that the studied adsorption may be a physical adsorption one.

In this research, adsorption of Zinc ion was investigated at batch system using spirulina microalgae and Magnetic microalgae. The effect of important parameters such as pH of the solution, absorbent contact time, the initial concentration of Zn(II) ion, adsorbent dosage and temperature were investigated on The removal efficiency and  adsorption capacity. Also adsorbent features were studied by using SEM photographs and FT-IR spectroscopy. The maximum Zinc ion adsorption occurred in pH=6. The optimum adsorbent dosages were determined 0.03 g for spirulina microalgae and Magnetic microalgae. So at optimum pH and adsorbents dosage for 150 mg/l initial zinc ion concentration 84.43% and 96.56% of removal efficiency was obtained for spirulina microalgae and Magnetic microalgae, respectively. Removal efficiency increased by increasing contact time between adsorbent and solution and after passing 10 min for spirulina microalgae and Magnetic microalgae reached to equilibrium. Examining kinetic models showed that pseudo-second order kinetic model had best fit for adsorbents. In investigating Zinc ion initial concentration in range of 50-300 mg/l, results showed by increasing initial concentration, efficiency decreased. Also experimental data of spirulina microalgae and Magnetic microalgae solutions had best fit by sips and Langmuir, respectively. Investigating temperature effect showed, by increasing temperature, removal efficiency decreased for spirulina microalgae and Magnetic microalgae. The thermodynamic parameter was studied in 298, 303, 313 and 323 Kelvin.