ارزيابي عمل كرد نانو ذرات دي اكسيد منگنز (MnO2) در حذف كادميم از محلول هاي آبي

Evaluation of the Efficiency of Manganese Dioxide Nano-particles (MnO2) in Cadmium Removal from Aqueous Solutions

زﻣﯿﻨﻪ و ﻫﺪف: اﻣﺮوزه از ﻓﻠﺰات ﺳﻨﮕﯿﻦ در ﺑﺴﯿﺎري از ﺻﻨﺎﯾﻊ و ﺗﮑﻨﻮﻟﻮژي ﻫﺎي ﻣﻬﻢ اﺳﺘﻔﺎده ﻣﯽ ﺷﻮد ﮐﻪ ﻧﺘﯿﺠﻪ آن ﺗﻮﻟﯿﺪ ﭘﺴﺎب ﻫﺎي ﺻﻨﻌﺘﯽ آﻟﻮده و ﻣﻀﺮ ﺑﺮاي ﺳﻼﻣﺘﯽ اﻧﺴﺎن و ﻣﺤﯿﻂ زﯾﺴﺖ اﺳﺖ. اﯾﻦ ﭘﮋوﻫﺶ ﺑﺎ ﻫﺪف ﺑﺮرﺳﯽ ﮐﺎراﯾﯽ ﺣﺬف ﮐﺎدﻣﯿﻢ از ﻣﺤﻠﻮل ﻫﺎي آﺑﯽ ﺑﺎ اﺳﺘﻔﺎده از ﺟﺎذب ﻣﻨﺎﺳﺐ و ﺟﺪﯾﺪ ﻧﺎﻧﻮ ذرات دي اﮐﺴﯿﺪ ﻣﻨﮕﻨﺰ ﺑﻮد. روش ﺑﺮرﺳﯽ: اﺑﺘﺪا ﻧﺎﻧﻮ ذرات دي اﮐﺴﯿﺪ ﻣﻨﮕﻨﺰ ﺑﻪ روش ﺗﺮﺳﯿﺐ اﻟﮑﺘﺮوﺷﯿﻤﯿﺎﯾﯽ ﮐﺎﺗﺪي ﺳﻨﺘﺰ ﮔﺮدﯾﺪ و ﺗﺎﺛﯿﺮ ﭘﺎراﻣﺘﺮﻫﺎي pH، زﻣﺎن ﺗﻤﺎس، ﻏﻠﻈﺖ ﻧﺎﻧﻮ ذرات و اﺛﺮ ﻏﻠﻈﺖ اوﻟﯿﻪ ﺑﺮ ﻓﺮآﯾﻨﺪ ﺟﺬب ﮐﺎدﻣﯿﻢ در ﺳﯿﺴﺘﻢ ﻧﺎﭘﯿﻮﺳﺘﻪ ﻣﻮرد ﺑﺮرﺳﯽ ﻗﺮار ﮔﺮﻓﺖ. ﺟﻬﺖ ﺗﻌﯿﯿﻦ وﯾﮋﮔﯽ ﻫﺎي ﻧﺎﻧﻮ ذرات دي اﮐﺴﯿﺪ ﻣﻨﮕﻨﺰ، از ﻣﯿﮑﺮوﺳﮑﻮپ اﻟﮑﺘﺮوﻧﯽ روﺑﺸﯽ)SEM(، دﺳﺘﮕﺎه ﭘﺮاش ﭘﺮﺗﻮ اﯾﮑﺲ)XRD( و دﺳﺘﮕﺎه ﻃﯿﻒ ﺳﻨﺞ ﻣﺎدون ﻗﺮﻣﺰ)FTIR( اﺳﺘﻔﺎده ﮔﺮدﯾﺪ. اﯾﺰوﺗﺮم ﻫﺎي ﺟﺬب ﻻﻧﮕﻤﯿﺮ و ﻓﺮﻧﺪﻟﯿﭻ و ﻧﯿﺰ ﺳﯿﻨﺘﯿﮏ ﻫﺎي ﺟﺬب ﮐﺎدﻣﯿﻢ ﺑﺮ روي ﺟﺎذب ﻧﺎﻧﻮ ذرات دي اﮐﺴﯿﺪ ﻣﻨﮕﻨﺰ ﺑﺮ اﺳﺎس ﻣﺪل ﻫﺎي ﻫﻮ و ﻫﻤﮑﺎران و ﻻﮔﺮﮔﺮن ﺑﺮرﺳﯽ ﺷﺪ. ﯾﺎﻓﺘﻪ ﻫﺎ: ﺗﺼﺎوﯾﺮ ﺗﻮﻟﯿﺪي ﺑﺎ ﻣﯿﮑﺮوﺳﮑﻮپ اﻟﮑﺘﺮوﻧﯽ روﺑﺸﯽ ﻧﺸﺎن داد ﮐﻪ اﻧﺪازه اﯾﻦ ذرات 30 ﺗﺎ 50 ﻧﺎﻧﻮﻣﺘﺮ اﺳﺖ. ﻧﺘﺎﯾﺞ ﻧﺸﺎن داد ﮐﻪ ﺑﺎ اﻓﺰاﯾﺶ pH، درﺻﺪ ﺣﺬف و ﻇﺮﻓﯿﺖ ﺟﺬب ﮐﺎدﻣﯿﻢ اﻓﺰاﯾﺶ ﯾﺎﻓﺖ و ﺑﻪ ﺣﺪاﮐﺜﺮ ﺧﻮد ﯾﻌﻨﯽ 54/8 درﺻﺪ رﺳﯿﺪ. اﻓﺰاﯾﺶ زﻣﺎن ﺗﻤﺎس ﺑﺎﻋﺚ اﻓﺰاﯾﺶ راﻧﺪﻣﺎن ﺟﺬب ﺷﺪ. در ﺑﺮرﺳﯽ اﯾﺰوﺗﺮم ﻫﺎي ﺟﺬب، داده ﻫﺎي آزﻣﺎﯾﺸﯽ از ﻣﺪل ﻻﻧﮕﻤﯿﺮ ﺗﺒﻌﯿﺖ ﮐﺮدﻧﺪ. ﻇﺮﻓﯿﺖ ﺟﺬب ﻻﻧﮕﻤﯿﺮ 42/016 ﻣﯿﻠﯽ ﮔﺮم ﺑﺮ ﮔﺮم ﺑﻪ دﺳﺖ آﻣﺪ. ﻫﻢ ﭼﻨﯿﻦ داده ﻫﺎي ﺑﻪ دﺳﺖ آﻣﺪه در اﯾﻦ ﺗﺤﻘﯿﻖ ﺑﺮاي ﺟﺎذب ﻧﺸﺎن داد ﮐﻪ ﺟﺬب ﮐﺎدﻣﯿﻢ از ﻣﺪل ﺳﯿﻨﺘﯿﮏ ﺷﺒﻪ ﻣﺮﺗﺒﻪ دوم ﺗﺒﻌﯿﺖ ﻣﯽ ﮐﻨﺪ. ﺑﺤﺚ و ﻧﺘﯿﺠﻪ ﮔﯿﺮي: ﻧﺘﺎﯾﺞ اﯾﻦ ﻣﻄﺎﻟﻌﻪ ﻧﺸﺎن داد ﮐﻪ اﺳﺘﻔﺎده از ﻧﺎﻧﻮ ذرات دي اﮐﺴﯿﺪ ﻣﻨﮕﻨﺰ ﺑﻪ ﻋﻨﻮان ﯾﮏ روش ﻣﻨﺎﺳﺐ ﺑﺎ ﭘﺘﺎﻧﺴﯿﻞ ﺑﺎﻻ در ﺣﺬف ﮐﺎدﻣﯿﻢ از ﻣﺤﻠﻮل ﻫﺎي آﺑﯽ ﻣﯽ ﺑﺎﺷﺪ.

Background: Today, heavy metals are used in many important industries and technologies, which result in the production of polluted industrial effluents that are harmful to human health and the environment. The aim of this study was to investigate the efficiency of cadmium removal from aqueous solutions using a suitable new adsorbent for manganese dioxide nanoparticles. Methods: In order to do this, manganese dioxide nanoparticles were synthesized using cathode electrochemical deposition method and the effect of pH, contact time, MnO2 concentration and cadmium concentration on cadmium removal efficiency were investigated in a batch system. Scanning electron microscope (SEM), XRD and FT-IR were used to identify the characterization of synthesized manganese dioxide nanoparticles. Results and Discussion: SEM results showed that the diameters of the particles were 30 to 50 nm. The other results showed that the optimum pH value for adsorption was 7. Contact time enhancement and the concentration absorbent are omitted because they make the efficiency boost. The adsorption capacity increased and the adsorption efficiency slightly increased with increasing concentration of cadmium and reducing the concentration adsorbent. Experimental data were shown the best to follow Langmuir model. Langmuir adsorption capacity, was found to be 42/016 mgg−1. The results also showed that the absorption of cadmium was obeyed from pseudo-second-order kinetic model. The overall results showed that the use of manganese dioxide nanoparticles was a suitable method with high potential for removal of cadmium from aqueous solutions.