Industrial development and water pollution with all kinds of pollutants have attracted the attention of researchers to investigate new, effective and environmentally friendly methods for removing pollutants from wastewater. In this research, a biodegradable magnetic hydrogel (St-g-PAA/CNFs) was synthesized in order to use it in a continuous adsorption process. First, by adding different amounts of magnetic nanoparticles to the hydrogel structure, swelling characteristics and adsorption of Cu2+ were investigated in the batch system. The physical, structural and morphological characteristics of the hydrogel as well as its magnetic properties were investigated before and after Cu2+ adsorption. Investigating the rate of swelling and isothermal adsorption of the process were among the other goals of this research. The results of the experiments showed a good compliance with the Langmuir isothermal model. For the hydrogel with 8 wt.% Fe3O4NPs, at pH = 5, the maximum Cu2+ adsorption capacity was obtained 555 mg/g. Due to the fact that wastewater treatment on a large scale is usually used as a continuous process, by designing a laboratory system including a column filled with strip steel coils under a magnetic field to disperse and keep the magnetic hydrogel grains on it and create a bed, Cu2+ adsorption experiments were eva‎luated as a continuous process. In the continuous adsorption experiments, the effect of various operational characteristics including the flow rate (8, 22 and 37 mL/min), Cu2+ concentration in the feed (90, 180 and 270 mg/L) and the amount of adsorbent in the bed (0.09 0.16 and 0.24 g) were investigated. In this regard, in order to develop the range of changes in the characteristics of the column and predict the performance of the column, the mathematical model of Cu2+ adsorption on hydrogel was derived. After solving the model equations in AnsysFluent software, the results were compared. Also, one of the most important features of the adsorption process is the possibility of adsorbent recovery. For this purpose, hydrochloric acid solution was used as a regenerating solution in discontinuous and continuous systems. The results showed that in the continuous process after three absorption/desorption cycles, the efficiency of the adsorption process decreased by 14.4%.

نسرين اعتصامي , طيبه بهزاد

ارجمند مهرباني زين آباد , مهرداد فرهاديان , صفورا كريمي