Abstract:
Calcon-imprinted magnetic chitosan (CIMC) nanoparticles (NPs) were successfully synthesized as a novel adsorbent. Epichlorohydrin (ECH) and glutaraldehyde (GA) were used as cross-linkers to synthesize desired calcon-imprinted magnetic chitosan (ECH/CIMC and GA/CIMC) and non-imprinted magnetic chitosan (ECH/NIMC and GA/NIMC) NPs for adsorption and removal of calcon from polluted solutions. Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) techniques were employed to investigate the characteristics of ECH/CIMC and GA/CIMC. The effect of pH, temperature, adsorbent dosage and initial dye concentration was evaluated. The adsorption isotherm and kinetics were adequately described by Langmuir and pseudo second-order model, respectively. Maximum removal capacity by ECH/CIMC and GA/CIMC was computed as 51.71 and 39.23 mg g-1.
Thermodynamic parameters were also estimated and results showed that the adsorption of calcon onto CIMC and NIMC was endothermic and that it is a spontaneous and favorable process.
 

 In this study, a new silver(I) coordination polymer (CP) containing bis(imidazolyl) ligand with fascinating crystal structure was used as an efficient adsorbent for the fast removal of Congo Red (CR) from aqueous solution. The structure of the silver(I)-CP was characterized by FT-IR spectroscopy and powder X-ray diffraction (PXRD).
Several important and effective parameters such as contact time, pH, temperature, and adsorbent mass were investigated to obtain optimal conditions for the removal of CR dye, in which 5 minutes, 6, 25˚C, and 0.005 g of adsorbent, were found for the aforementioned optimization results, respectively. The utilized Ag(I) coordination polymer in this study exhibited a much higher maximum absorption capacity (1000 mg g-1) compared to other previous adsorbents for the removal of CR, reported in the literature. The adsorption kinetics of CR on Ag(I)-CP followed the pseudo-second-order kinetic model. The equilibrium adsorption data were well represented by Langmuir isotherm equation. Moreover, the study of thermodynamic parameters demonstrated that the adsorption process is spontaneous, endothermic, and associated with an increase in entropy.

In this study the removal of amaranth (AM) from an aqueous solution by iron oxide nanoparticles coated with glutamic acid as adsorbent was reported. In order to obtain maximum removal efficiencies, effects of pH, kind of buffer, volume of buffer, amount of adsorbent, ionic strength, time of stirring, volume of solution and interfering ions were investigated. Maximum removal efficiencies were obtained at pH=3. Adsorption kinetics of the dye was second-order kinetic model . Dye adsorption equilibrium data were fitted well to the Langmuir isotherm and the maximum capacity ,qmax, was calculated from the Langmuir as 106.38 mg g−1. This method was used for removal of AM from aqueous  solutions.

Precence of thiocyanate causes increased pollution in Industrial wastewater.In this research, magnetic nano particles modified by chitosan-Fe (III) used as an efficient adsorbent for removal of thiocyanate from aqueous solutions. Removal percentage of thiocyanate by modified magnetic nanoparticels is more than magnetic non- modified nanoparticles.The effects of different parameters such as pH , amount of adsorbent, time of stirring and temperature on the removal of thiocyanate has been investigated . Maximum removal percentage (96.7%) was obtained at pH= 4 , 0.03g of adsorbent and stiring time of 10 min. The results showed that maximum adsorption capacity of the adsorbent is 88 mg g-1. The experimental data were correlated reasonably well by Langmuir adsorption isotherm. Kinetic data were well fitted by a pseudo-second order model.methanol :aceton solution was applied to regenerate the adsorbent.The results showed that adsorbent could retain its high efficiency after several times of desorption and regeneration.This method is simple,cheap and it could efficiently remove thiocyanate from aqueous solutions

  In this study, Removed of Cr (VI) ion from water samples by magnetic nano particle modified by Chitosan adsorbent. The ability of Chitosan modified magnetic Nano particle as an efficient adsorbent for removal of Cr (VI) from water samples was investigated. In order to obtain maximum removal efficiencies, effects of pH, kind of buffer, volume of buffer, amount of adsorbent, ionic strength, time of stirring, volume of solution and interfering ions were investigated. Concentration determination of Cr (VI) was monitored by UV-Vis spectrophotometric method at 577 nm. Maximum removal efficiencies were obtained at pH=4.5. In order to obtain maximum capacity of adsorbent, Langmuir adsorption isotherm in the optimum condition was plotted and it was illustrated that adsorbent capacity is 217.39 mg g-1. This method was successfully used for removal of Cr (VI) from spiked water samples such as Karon river water and tap water of Ahwaz and Mahshahr.
In this study, the efficiency of chitosan-modified magnetic nano particlesas for preconcentration and separation of reactive red 2 and crystal violet was investigated. Absorbances of Reactive red 2 and crystal violet were measured at 548 nm and 592 nm, respectivety. The calibration graphs were linear in range 10- 120 ng mL-1 for reactive red and 10-240 ng mL-1 for crystal violet with R2=0.995 and R2= 0.995,respectivety relative standard deviation (RSD) for 60 ng mL-1 of Reactive red 2 was 3.17% and for 60 ng mL-1 crystal violet was 2.86%, Detection limit were2.4 ng mL-1 and.0.48 ng mL-1 for reactive red 2 and crystal violet, respectively. The method was applied for determination of Reactive red 2 and crystal violet in karon river water and tap water of Ahwaz and Mahshahr.

In this study, Removed of Rective Red 2 (RR 2) dye from water samples by magnetic nano particle modified by L-tryptophan adsorbent. The ability of L-tryptophan modified magnetic Nano particle as an efficient adsorbent for removal of RR 2 from water samples was investigated. In order to obtain maximum removal efficiencies, effects of pH, kind of buffer, volume of buffer, amount of adsorbent, ionic strength, time of stirring, volume of solution and interfering ions were investigated. Concentration determination of RR 2 was monitored by UV-Vis spectrophotometric method at 546 nm . Maximum removal efficiencies were obtained at pH=3. In order to obtain maximum capacity of adsorbent, Langmuir adsorption isotherm in the optimum condition was plotted and it was illustrated that adsorbent capacity is 113.63 mg g-1. This method was successfully used for removal of RR 2 from spiked water samples such as Jarahi river water and tap water of Ahwaz and Mahshahr.
In the second research, a sensitive preconcentration procedure has been developed for determination of Reactive Red 2 (RR 2) dye by spectrophotometry. The method is based on adsorption of RR 2 on magnetic Nano particle modified by L-tryptophan, elution by ammonia buffer (pH =10) and measurement of its absorbance at maximum wavelength of 546 nm. A preconcentration factor 100 was obtained using the optimum conditions. Effects of the major independent variables (concentration, adsorbent dose and pH) and their interactions during uptake of RR 2 were determined by Response Surface Methodology (RSM) based on the central composite design. Optimized values of adsorbent nanoparticle dosage, pH and concentration for RR 2 adsorption were found as 0.1 g , 5 and 50 ng mL-1, respectively. The calibration graph was linear
in the range of 10- 400 ng mL-1 RR 2 in initial solution with R2=0.9989. Detection limit was 1.82 ng mL-1 and relative standard deviation (RSD) for 50 and 250 ng mL-1 of RR 2 was 2.3% and 4.79% ,respectively. The method was applied for determination of RR 2 in Jarahi river water and tap water of Ahwaz and Mahshahr.

<p>در این تحقیق از روش استخراج فاز جامد جهت حذف رنگ دایرکت بلو 86 از پساب کارخانه ی کاغذ سازی استفاده شده است. این روش بر اساس جذب سطحی دایرکت بلو 86 بر روی ستون حاوی کیتوسان نهیه شده از بوشت میگو و اندازه گیری میزان حذف با استفاده از دستگاه اسپکتروفتومتر UV-Vis می باشد. در این پروژه اثر پارامتر های مختلف ماندد میزان جرم جاذب، pH، سرعت عبور محلول از روی ستون، نوع و غلظت نمک، نوع و معدار بافر، بازجذب رنگ از روی جاذب و همچنین اثر یون های مزاحم به منظور دسترسی به بالاترین میزان حذف آنالیت مورد بررسی قرار گرفت. همچنین منحنی جذب سطحی لانگمویر رسم گردید که نتایج نشان دهنده حداکثر60 میلی گرم بر گرم جاذب می باشد. منحنی کالیبراسیون در محدوده ی-1 mg L 60-1 خطی بود. از این روش به منظور حذف رنگ دایرکت بلو 86 از پساب کارخانه ی کاغذسازی پارس و آب رودخانه ی کارون استفاده شد. از آنجا که در حضور H+گروه های آمین کیتوسان پروتونه می شوند، بدلیل برهمکنش های الکترواستاتیک بین آنیون های آنالیت و گروه های آمین کیتوسان ، فرآیند حذف رنگ انجام می گیرد. از آنجا که کیتوسان جاذب زیستی می باشد که از ضایعات صنایع شیلات قابل تهیه است و ظرفیت جذب بالای دارد و همچنین غیر سمی بوده و سازگار با محیط زیست می باشد و در طبیعت قابل تجزیه است، میتوان از آن به عنوان جاذب استفاده کرد.</p>