.In this research, the nanofiber filter reinforced with zeolite was investigated as an available an‎d inexpensive adsorbent for the removal of heavy metals, including chromium (Cr), from aqueous solutions. The nanofiber filter reinforced with zeolite has a wide range of applications due to its high specific surface area, porous structure, an‎d impressive chemical properties. One of the applications of the nano fiber filter is to purify water an‎d wastewater containing heavy metals, in order to prevent environmental problems caused by the entry of heavy metals into the environment. To make a nanofiber filter reinforced with zeolite, first, natural zeolite was washed with city water for 24 hours an‎d then dried at a temperature of 70 degrees celsius. 88% formic acid an‎d polyamide 6 granules were mixed for 24 hours by a magnetic stirrer an‎d finally the desired solution was homogenized by an ultrasonic device. After preparing the desired solution, an electrospinning machine was used to produce fibers in nano dimensions. The characteristics of the nanofiber filter reinforced with zeolite were determined using XRD, SEM-EDX analyses. In the next step, the sorption of Cr was investigated by nano fiber filter. Adsorption tests were designed in a discontinuous an‎d columnar experiments, an‎d the factors affecting the sorption rate, such as pH (3, 5, 7, 9), contact time (15, 30, 60, 120 minutes), sorption dose (0%, 1%, 3%, 5%), filter surface area (1,2, 3 an‎d 4 cm2), an‎d initial metal concentration (1, 10, 20 an‎d 40 ppm) were investigated. The results showed that the optimal pH for sorption of more than 90% of Cr was equal to 3 an‎d the minimum sorption effieicency was obtained at pH 9. By increasing the percentage of zeolite from 0 to 5%, the sorption of Cr increased with a Cr concentration of 20 ppm. The maximum Cr sorption occurred after 120 minutes, an‎d after that, the efficiency decreased. Increasing the filter surface from 1 to 4 cm2 showed that the maximum Cr sorption from a 20 ppm Cr solution was obtained by the filter with a surface of 4 cm2. Sorption kinetics revealed a better fit of the pseudo-second-order model, an‎d Cr sorption showed a better fit by Langmuir isotherm model than Freundlich model. The column experiments showed that the nanofiber filter modified with zeolite had the a 50% sorption efficiency from 20 ppm Cr solution. The results showed the high potential of the nanofiber filter modified with zeolite to remove Cr from aqueous solutions, which requires further investigation in wastewater containing this element.

محسن سليماني امين آبادي

صديقه برهاني

اميدوار فرهاديان , نوراله ميرغفاري