جذب فلز سنگين جيوه از محلول هاي آبي به وسيله نانوذرات مغناطيسي عامل دار شده با آمين

Adsorption of Mercury (II) Metal from Aqueous Solutions by Amine-Functionalized Magnetic Nano-particles

زﻣﯿﻨﻪ و ﻫﺪف: اﻣﺮوزه آﻟﻮدﮔﯽ ﺑﻮمﺳﺎزﮔﺎن آﺑﯽ ﺑﻪ ﻓﻠﺰات ﺳﻤﯽ ﺑﻪﺧﺼﻮص ﺟﯿﻮه از ﻧﮕﺮاﻧﯽﻫﺎي ﻣﻬﻢ ﺟﻬﺎﻧﯽ ﺑﻪ ﺷﻤﺎر ﻣﯽرود. اﺳﺘﻔﺎده از ﻧﺎﻧﻮ ﺟﺎذبﻫﺎ روﺷﯽ ﻧﻮﯾﻦ ﺑﺎ ﮐﺎراﯾﯽ ﺑﺎﻻ ﺟﻬﺖ ﺣﺬف ﻓﻠﺰات ﺳﻨﮕﯿﻦ از ﻣﺤﯿﻂﻫﺎي آﺑﯽ اﺳﺖ. در اﯾﻦ ﻣﻄﺎﻟﻌﻪ ﺑﻪ ﻣﻨﻈﻮر ﺣﺬف ﯾﻮن ﺟﯿﻮه از ﻣﺤﻠﻮل-ﻫﺎي آﺑﯽ و ﭘﺴﺎب ﮐﻠﺮوآﻟﮑﺎﻟﯽ، ﻧﺎﻧﻮﮐﺎﻣﭙﻮزﯾﺖFe3O4@SiO2-NH2 ﻋﺎﻣﻞ دار ﺷﺪه ﺑﺎ ﮔﺮوه آﻣﯿﻨﯽ APTMS ﺳﻨﺘﺰ ﺷﺪ. روش ﺑﺮرﺳﯽ: آﻧﺎﻟﯿﺰﻫﺎي ﮔﺮﻣﺎ وزنﺳﻨﺠﯽ، ﻣﯿﮑﺮوﺳﮑﻮپ اﻟﮑﺘﺮوﻧﯽ روﺑﺸﯽ، ﻃﯿﻒ ﺳﻨﺠﯽ ﻣﺎدون ﻗﺮﻣﺰ ﺗﺒﺪﯾﻞ ﻓﻮرﯾﻪ، و آﻧﺎﻟﯿﺰ ﺗﻌﯿﯿﻦ ﻗﺪرت ﻣﻐﻨﺎﻃﯿﺴﯽ ﺑﻪ ﻣﻨﻈﻮر ﺗﺸﺨﯿﺺ و ﺑﺮرﺳﯽ وﯾﮋﮔﯽﻫﺎي ﻧﺎﻧﻮﮐﺎﻣﭙﻮزﯾﺖ ﺳﻨﺘﺰ ﺷﺪه ﺻﻮرت ﭘﺬﯾﺮﻓﺖ. ﺳﭙﺲ اﯾﻦ ﻧﺎﻧﻮﮐﺎﻣﭙﻮزﯾﺖ ﺑﺮاي ﺣﺬف ﻓﻠﺰ ﺟﯿﻮه از ﻣﺤﻠﻮلﻫﺎي آﺑﯽ و ﭘﺴﺎب ﮐﻠﺮوآﻟﮑﺎﻟﯽ در ﺳﯿﺴﺘﻢ ﻧﺎﭘﯿﻮﺳﺘﻪ ﻣﻮرد ﻣﻄﺎﻟﻌﻪ ﻗﺮار ﮔﺮﻓﺖ. ﺟﺬب ﺟﯿﻮه در ﺷﺮاﯾﻂ ﺑﻬﯿﻨﻪ )6 :pH، زﻣﺎن: 90 دﻗﯿﻘﻪ، ﻣﻘﺪار ﺟﺎذب: 20 ﻣﯿﻠﯽ ﮔﺮم( ﻣﻮرد ﺑﺮرﺳﯽ ﻗﺮار ﮔﺮﻓﺖ. ﯾﺎﻓﺘﻪ ﻫﺎ: ﻧﺘﺎﯾﺞ ﺑﯿﺸﺘﺮﯾﻦ ﻇﺮﻓﯿﺖ ﺟﺬب ﺗﻌﺎدﻟﯽ ﺑﺮاي ﺣﺬف ﺟﯿﻮه از ﻣﺤﻠﻮل ﻫﺎي آﺑﯽ 130/45 اﻧﺪازه ﮔﯿﺮي ﺷﺪ. درﺻﺪ ﺣﺬف ﺟﯿﻮه از ﭘﺴﺎب واﻗﻌﯽ ﺣﺪود 55 % ﺑﺮآورد ﮔﺮدﯾﺪ. ﺑﻪﻋﻼوه از ﻣﯿﺎن ﻣﺪلﻫﺎي ﻫﻢدﻣﺎي ﺟﺬﺑﯽ ﻣﺪل ﻻﻧﮕﻤﻮﯾﺮ ﺑﻪ ﻋﻨﻮان ﻣﺪل ﻣﻨﺎﺳﺐ ﺑﺮاي اﯾﻦ ﺟﺎذب ﺑﺮازش ﯾﺎﻓﺖ ﮐﻪ ﻧﺸﺎن دﻫﻨﺪه ﺟﺬب ﺗﮏﻻﯾﻪ اﺳﺖ. ﺑﺎزﯾﺎﺑﯽ ﺟﺎذب ﺳﻨﺘﺰ ﺷﺪه ﻃﯽ ﭘﻨﺞ ﭼﺮﺧﻪ ﻣﺘﻮاﻟﯽ ﺟﺬب-واﺟﺬب ﺗﻮﺳﻂ اﺳﯿﺪ ﮐﻠﺮﯾﺪرﯾﮏ 0/8 ﻣﻮﻻر اﻧﺠﺎم ﮔﺮﻓﺖ ﮐﻪ از ﭼﺮﺧﻪ اول ﺗﺎ ﭼﺮﺧﻪ ﭘﻨﺠﻢ ﺣﺪود 15 % ﮐﺎﻫﺶ ﻧﺸﺎن داد. ﺑﺤﺚ و ﻧﺘﯿﺠﻪ ﮔﯿﺮي: ﻧﺘﺎﯾﺞ ﻧﺸﺎن دادﻧﺪ ﻧﺎﻧﻮﮐﺎﻣﭙﻮزﯾﺖ ﺳﻨﺘﺰ ﺷﺪه در اﯾﻦ ﺗﺤﻘﯿﻖ از ﻇﺮﻓﯿﺖ ﺟﺬب ﻧﺴﺒﺘﺎً ﺑﺎﻻﯾﯽ ﺑﺮاي ﺟﺬب ﯾﻮن ﺟﯿﻮه ﺑﺮﺧﻮردار ﺑﻮده و ﻗﺎﺑﻠﯿﺖ ﺑﺎزﯾﺎﺑﯽ و اﺳﺘﻔﺎده ﻣﺠﺪد اﯾﻦ ﺟﺎذب، ﺑﻪﮐﺎرﮔﯿﺮي آن را در ﺳﯿﺴﺘﻢ ﺗﺼﻔﯿﻪ ﭘﺴﺎب از ﻧﻈﺮ اﻗﺘﺼﺎدي ﺗﻮﺟﯿﻪﭘﺬﯾﺮ ﻣﯽﻧﻤﺎﯾﺪ.

Background and Objective: Nowadays, pollution of aquatic ecosystems with toxic metals, especially mercury, is one of the major concerns of the world. The use of nano-adsorbents is a novel high-performance method for removing heavy metals from aqueous media. In this study, in order to remove of Hg (II) from aqueous solutions and chloro-alkali wastewater, amine functionalized-Fe3O4@SiO2-NH2 nanocomposite was synthesized. Method: As-synthesized nano-composite was characterized by thermo-gravimetric analysis, scanning electron microscopy, Fourier Transform Infrared spectroscopy, and vibrating sample magnetometry. The nano-composite was used for removal of Hg (II) ions from aqueous solution and chloro-alkali wastewater in batch system. Findings: The maximum equilibrium adsorption capacities for Hg (II) ions from aqueous solution 137.45 mg/g were calculated. Percentage of mercury removal from real wastewater was estimated about 55%. Sorption of Hg (II) ions with Fe3O4@SiO2-NH2 agreed well to the Langmuir isotherm model, confirming a monolayer adsorption. Desorption study showed that adsorbed metals could easily be desorbed from the adsorbent by 0.8 M HCl for Hg(II) ions, that the desorption percentage efficiencies was reduced from first to fifth cycle times about 15 %. Discussion and Conclusion: The results showed that the synthesized nanocomposite in this research has a relatively high adsorption capacity for Hg (II) ions adsorption, also according to its recyclability and reusability, the application of this adsorbent in wastewater treatment system could be reasonable in terms of the economic aspect.