مطالعه حذف نيترات از پساب با استفاده از نانو فوتوكاتاليست Fe-TiO2

Experimental study of nitrate removal from wastewater using Fe-TiO2 nanophotocatalyst

ﯿﺪه: در اﯾﻦ ﻣﻄﺎﻟﻌﻪ، در اﺑﺘﺪا ﻧﺎﻧﻮ ﻓﺘﻮﮐﺎﺗﺎﻟﯿﺴﺖ دي اﮐﺴﯿﺪ ﺗﯿﺘﺎﻧﯿﻮم /آﻫﻦ ﺑﺎ روش ﺳﻞ ژل ﺳﻨﺘﺰ ﮔﺮدﯾﺪ.ﺳﺎﯾﺰ ﻣﺘﻮﺳﻂ ﻧﺎﻧﻮ ﻓﺘﻮ ﮐﺎﺗﺎﻟﯿﺴﺖ ﺳﻨﺘﺰ ﺷﺪه در ﺣﺪود28-47 ﻧﺎﻧﻮﻣﺘﺮﻣﯽ ﺑﺎﺷﺪ. ﻫﺪف اﺳﺘﻔﺎده از ﺗﺎﺑﺶ UV و ﻧﺎﻧﻮ ﻓﺘﻮﮐﺎﺗﺎﻟﯿﺴﺖ/UV در ﺣﺬف ﻧﯿﺘﺮات از ﭘﺴﺎب ﻣﯽ ﺑﺎﺷﺪ. ﻏﻠﻈﺖ ﻫﺎي ﻣﻮرد ﺑﺮرﺳﯽ ﻧﯿﺘﺮات در اﯾﻦ ﺗﺤﻘﯿﻖ ﺷﺎﻣﻞ ﻏﻠﻈﺖ ﻫﺎي 50 ﺗﺎ130 ﻣﯿﻠﯽ ﮔﺮم در ﻟﯿﺘﺮ ﺑﻮد. ﺑﻪ ﻣﻨﻈﻮر ﺗﻌﯿﯿﻦ ﻣﻘﺪار ﺑﻬﯿﻨﻪ ﻏﻠﻈﺖ ﻧﺎﻧﻮ ﻓﺘﻮﮐﺎﺗﺎﻟﯿﺴﺖ در اﺣﯿﺎي ﻧﯿﺘﺮات از ﻏﻠﻈﺖ ﻫﺎي0 .1 ﺗﺎ0 .6 ﻣﯿﻠﯽ ﮔﺮم در ﻟﯿﺘﺮ اﺳﺘﻔﺎده ﺷﺪ. ﺑﺮاي ﺗﻌﯿﯿﻦpH ﺑﻬﯿﻨﻪ ﻧﯿﺰ از pH2 ﺗﺎ 9 اﺳﺘﻔﺎده ﺷﺪ. زﻣﺎن ﻫﺎي ﺗﺎﺑﺶ و دﻣﺎ ﻣﻮرد ﺑﺮرﺳﯽ ﺑﻪ ﺗﺮﺗﯿﺐ 30ﺗﺎ180 دﻗﯿﻘﻪ و20ﺗﺎ40 درﺟﻪ ﺳﺎﻧﺘﯽ ﮔﺮاد اﺳﺘﻔﺎده ﺷﺪ. ﺑﺎ اﻓﺰاﯾﺶ زﻣﺎن راﻧﺪﻣﺎن ﺣﺬف ﻓﺘﻮﮐﺎﺗﺎﻟﯿﺴﺘﯽ ﻧﯿﺘﺮات اﻓﺰاﯾﺶ ﯾﺎﻓﺘﻪ وﻟﯽ ﺑﺎ اﻓﺰاﯾﺶ ﻏﻠﻈﺖ اﯾﻦ روﻧﺪ ﻧﺰوﻟﯽ ﺑﻮده اﺳﺖ.ﺑﻬﯿﻨﻪ ﺗﺮﯾﻦ ﺣﺎﻟﺖ ﺣﺬف در ﻏﻠﻈﺖ اوﻟﯿﻪ 50 ﻣﯿﻠﯽ ﮔﺮم ﺑﺮ ﻟﯿﺘﺮ و زﻣﺎن120 دﻗﯿﻘﻪ ﺣﺎﺻﻞ ﺷﺪه اﺳﺖ ﮐﻪ اﯾﻦ ﻣﻘﺪار ﺣﺬف ﺑﺮاﺑﺮ ﺑﺎ 87 .7 درﺻﺪ ﻣﯽ ﺑﺎﺷﺪ. راﻧﺪﻣﺎن ﺑﻬﯿﻨﻪ pH در ﺣﺬف ﻧﯿﺘﺮات ﺗﻮﺳﻂ ﻧﺎﻧﻮ ﻓﺘﻮﮐﺎﺗﺎﻟﯿﺴﺖ ﺑﺮاﺑﺮ ﺑﺎ 5 ﺑﻮده اﺳﺖ ﮐﻪ 89 درﺻﺪ ﻣﯽ ﺑﺎﺷﺪ ﮐﻪ ﻧﺸﺎن ﻣﯽ دﻫﺪ ﺑﻬﺘﺮﯾﻦ راﻧﺪﻣﺎن ﺣﺬف در ﺷﺮاﯾﻂ اﺳﯿﺪي رخ داده اﺳﺖ. ﺑﯿﺸﺘﺮﯾﻦ ﻣﻘﺪار ﺣﺬف ﻧﯿﺘﺮات در ﻏﻠﻈﺖ 0 .5 ﻣﯿﻠﯽ ﮔﺮم ﺑﺮ ﻟﯿﺘﺮ ﻧﺎﻧﻮ ﻓﺘﻮ ﮐﺎﺗﺎﻟﯿﺴﺖ ﻣﯽ ﺑﺎﺷﺪ ﮐﻪ ﺑﺮاﺑﺮ ﺑﺎ 89 .1 درﺻﺪ ﺑﻮده اﺳﺖ.ﺑﺎ اﻓﺰاﯾﺶ دﻣﺎ از 20 ﺗﺎ 40 درﺟﻪ ﺳﺎﻧﺘﯽ ﮔﺮاد راﻧﺪﻣﺎن ﺣﺬف ﻧﯿﺘﺮات از 54 ﺑﻪ 91 درﺻﺪ اﻓﺰاﯾﺶ ﭘﯿﺪا ﻣﯽ ﮐﻨﺪ.از ﺑﯿﻦ ﻣﺮاﺣﻞ اﻧﺠﺎم ﺷﺪه، اﺳﺘﻔﺎده از ﭘﺮﺗﻮ UV ﺑﻪ ﺗﻨﻬﺎﯾﯽ ﺑﺮاي ﺣﺬف ﻧﯿﺘﺮات ﮐﺎراﯾﯽ ﻧﺪارد اﻣﺎ ﺑﻪ ﻧﻈﺮ ﻣﯽ رﺳﺪ ﮐﻪ اﺳﺘﻔﺎده از ﻓﺮاﯾﻨﺪ ﻧﺎﻧﻮ ﻓﺘﻮﮐﺎﺗﺎﻟﯿﺴﺖUV ﮐﺎراﯾﯽ ﺧﻮﺑﯽ در ﺣﺬف ﻧﯿﺘﺮات دارد.

In this study, the first nano photocatalyst titanium dioxide / iron were synthesized by sol-gel method. The average size of about 28-47 nm is synthesized nano-photocatalysts.The purpose of using UV irradiation and nano photocatalyst /UV nitrate removal from wastewater. Nitrate concentrations in this study were evaluated 50 concentrations to 130 mg per liter.In order to determine the optimum concentration of nitrate concentrations in the revival of photocatalyst nano 0.1-0.6 mg/Lit was used. To determine the optimum pH from pH, 2 to 9 were used. Exposure time and temperature, respectively and 30-180 min and 20-40 ° C was used. Photocatalytic nitrate removal efficiency increased with increasing duration but by increasing the concentration has been declining.The most efficient mode of eliminate the initial concentration of 50 ppm and 120 minutes of time is the amount equal to 87.7 percent is removed.pH optimum efficiency for nitrate removal by nano photocatalyst, which is equal to 2 percent is 89 that shows the best removal occurred in acidic conditions.The highest value in concentration of 0.5 mg photocatalytic nano is equivalent to 89.1 percent.Increasing the temperature from 20 to 40 ° C nitrate removal efficiency of 54 to 91 percent increase.Among the steps taken, the use of UV light to remove nitrate does not work alone, but it seems that the process of photocatalyst nano / UV nitrate removal efficiency is good