ﺗﺄﺛﯿﺮ ﻣﺎده آﻟﯽ ﺧﺎک ﺑﺮ ﺳﯿﻨﺘﯿﮏ و ﺗﺮﻣﻮدﯾﻨﺎﻣﯿﮏ ﺟﺬب ﻓﺴﻔﺮ

نوع مقاله: مقاله پژوهشی

نویسندگان

1 داﻧﺸﺠﻮی ﺳﺎﺑﻖ ﮐﺎرﺷﻨﺎﺳﯽ ارﺷﺪ ﮔﺮوه ﻋﻠﻮم و ﻣﻬﻨﺪﺳﯽ ﺰ

2 ﮔﺮوه ﻋﻠﻮم و ﻣﻬﻨﺪﺳﯽ خاک دانشگاه تبریز

چکیده

ﺑﻪ ﺮ ﻧﻈ ﻣﯽ رﺳﺪ ﮐﻪ وﺟﻮد ﯽ ﻣﻮاد آﻟ ک در ﺧﺎ ر ﻓﺮاﻫﻤﯽ ﻓﺴﻔﺮ ﺑﻪ ﮔﯿﺎﻫﺎن  ا اﻓﺰاﯾﺶﻣﯽدﻫ ﻦ ﺪ .اﯾ ﺑ ﺗﺄﺛﯿﺮ ﻪ ﺑﻪ ﻃﻮر ﻋﻤﺪه ﺻﻮرت ن رﻗﺎﺑﺖ ﺑﯿﻦ ﻣﺤﺼﻮﻻت ﺣﺎﺻﻞ از ﺗﺠﺰﯾﻪ ﻣﻮاد آﻟﯽ و ﻓﺴﻔﺮ ﺑﺮای ﺟﺬب ﻣﮑﺎ ﻫﺎی ﺧﺎک ﺻ ﺗﻮ ﯿﻒﺷﺪه  اﺳﺖ ﮐﻪ ﻣﻨﺠﺮ ﺑﻪ اﻓﺰاﯾﺶ ﻏﻠﻈﺖ ﻓﺴﻔﺮ ﻣﺤﻠﻮل ﻣﯽ ﺷﻮد .اﯾﻦ ﺗﺤﻘﯿﻖ ی ﺑﺮا  ﮐﺴﺐ اﻃﻼﻋﺎت د در ﻣﻮر ﺗﺄ ﺛﯿﺮ ﻣﺎده آﻟﯽ ﺧﺎک ﺑﺮ ﺳﯿﻨﺘﯿﮏ و ﺗﺮﻣﻮدﯾﻨﺎﻣﯿﮏ آ 3 ﺟﺬب ﻓﺴﻔﺮ در ﻧﻤﻮﻧﻪ ﺧﺎک  ﻫﮑﯽ ﻊ ﺟﻤ آوریﺷﺪه  . از اﺳﺘﺎن آذرﺑﺎﯾﺠﺎن ﺷﺮﻗﯽ اﻧﺠﺎم ﮔﺮﻓﺖ ﺎ آزﻣﯾ ﺳ ﺶ ﯿﻨﺘﯿ ﮏ ﺟﺬب ﻓﺴﻔﺮ در ﻏﻠﻈﺖ اوﻟﯿ  1 ﻪ ﻣﯿﻠﯽ ﻟ 00 ﮔﺮم ﻓﺴﻔﺮ در ﯿ) B ﺘﺮ ﻗﺒﻞ  آﻟ A) (و ﺑﻌﺪ (از ﺣﺬف ﻣﺎده ﯽ   3 ﺗﺎ 36  . ﺳﺎﻋﺖ اﻧﺠﺎم ﮔﺮﻓﺖ ﺧﺎک ﻣﺎده آﻟﯽ   ﺑﺎ N ) ﻣﺤﻠﻮل ﻫﯿﭙﻮﮐﻠﺮﯾﺖ ﺳﺪﯾﻢ ب aOCl (ﺣﺬف ﮔﺮدﯾﺪ .ﺑﺮ ﻃﺒﻖ ﻧﺘﺎﯾﺞ ﺣﺎﺻﻠﻪ ﺟﺬ ﺧﺎک ﻓﺴﻔﺮ ﺗﻮﺳﻂ    48 ﻫﺎ در اﺑﺘﺪا ﺗﺎ ﺳﺎﻋﺖ ﺳﺮﯾﻊ و  دوم و ﻣﺮﺗﺒﻪ ﺳﻮم ﻧﺘﻮاﻧﺴﺘﻨﺪ ﺳﯿﻨﺘﯿ ، اول ، ﺳﭙﺲ ﺑﻪ آﻫﺴﺘﮕﯽ اداﻣﻪ ﯾﺎﻓﺖ .ﻣﻌﺎدﻻت ﻣﺮﺗﺒﻪ ﺻﻔﺮ ﮏ . ﺟﺬب ﻓﺴﻔﺮ را ﺗﻮﺻﯿﻒ ﮐﻨﻨﺪ ﺳﻪ ﻣﻌﺎدﻟﻪ اﻟﻮوﯾﭻ ه ﺳﺎد ﺷﺪه ﺗ ﭘﺨﺸﯿﺪﮔﯽ ﭘﺎراﺑﻮﻟﯿﮏ و دو ﺛﺎﺑﺘﻪ ﺑﺮازش ﺧﻮﺑﯽ داﺷﺘﻨﺪ وﻟﯽ ﻣﻌﺎدﻟﻪ دو ﺛﺎﺑﺘﻪ ﻣﻌﺎدﻟﻪ ﺑﺮ د ، ﺮ ﺑﻮ . ﺑﺮای    4 ﺟﺬب ﻓﺴﻔﺮ در ، ﺑﺮرﺳﯽ ﺗﺄﺛﯿﺮ دﻣﺎ 10 دﻣﺎی ،20 ،30   ه 40و درﺟﻪ ﺳﻠﺴﯿﻮس اﻧﺪاز ﮔﯿﺮی ﺷﺪ .ﺑﺮ ﻃﺒﻖ ﻧﺘﺎﯾﺞ ﺣﺎﺻﻠﻪ ﺟﺬب ﻓﺴﻔﺮ ﻗﺒﻞ و ﺑﻌﺪ از ﺣﺬف ﻣﺎده آﻟﯽ ﺑﺎ اﻓﺰاﯾﺶ دﻣﺎ اﻓﺰاﯾﺶ ﯾﺎﻓﺖ ﮐﻪ ن ﻧﺸﺎ ﺪه دﻫﻨ  ﮔﺮﻣﺎﮔﯿﺮ ﺑﻮدن ﺳﺮﺷﺖ واﮐﻨﺶ ﺟﺬب ﻓﺴﻔﺮ ﻫﺴﺖ ﺮ .ﻣﻘﺎدﯾ ﻔ ﻣﻨﯽ ﺮژ اﻧ ی ﮔ آزاد ﯿ د در ﺎ ،ﺒﺲ ﻣﺎﻫی  ﻣﺨﺘﻠﻒ ن ﻧﺸﺎ ﺪه دﻫﻨ ﻫ ﻣﺎ ﯿ د ﺖ ﺧﻮد ﺑﻪ ﺧﻮ ی  ﺟﺬب ﻓﺴﻔﺎتﺑﻪوﺳﯿﻠﻪ ک ﺧﺎ ﻫﺎی ﻣﻮردﻣﻄﺎﻟﻌﻪ د ﺑﻮ ک .ﻗﺒﻞ از ﺣﺬف ﻣﺎده آﻟﯽ ﺧﺎ ∆ ﺑﺎ اﻓﺰاﯾﺶ دﻣﺎ ﻣﯿﺎﻧﮕﯿﻦ ،ﻫﺎ G0      -32/0 در ﻣﮑﺎن اول ﺟﺬﺑﯽ از  -38/2ﺑﻪ ﮐﯿﻠﻮژول   -25/4 ﺑﺮ ﻣﻮل و در ﻣﮑﺎن دوم از - ﻟﯽ 28/4ﺗﺎ  درﺣﺎ ، ﮐﯿﻠﻮژول ﺑﺮ ﻣﻮل اﻓﺰاﯾﺶ ﯾﺎﻓﺖ ﮐﻪ ﺑﻌﺪ از ﺣﺬف ﻣﺎده آﻟﯽ  داﻣﻨﻪ ﺗﻐﯿﯿﺮات   -32/9 ﻣﺬﮐﻮر  در ﻣﮑﺎن اول از   -39/3ﺗﺎ  -30/9 ﮐﯿﻠﻮژول ﺑﺮ ﻣﻮل و در ﻣﮑﺎن دوم از .  -36/9ﺗﺎ ﮐﯿﻠﻮژول ﺑﺮ ﻣﻮل ﺑﻮد  

موضوعات


عنوان مقاله [English]

Effects of Soil Organic Matter on Kinetics and Thermodynamics of Phosphorous Sorption

نویسندگان [English]

  • M Ma hdizadeh 1
  • A Reyhanitabar 2
  • S Oustan 2
چکیده [English]

It seems that the presence of soil organic matter (SOM) increases P availability to plants. This effect has commonly been ascribed as competition between the decomposition products of SOM and P for soil sorption sites resulting in P concentrations increase of soil solution. This study was carried out to obtain information about soil organic matter (SOM) influence on kinetics and thermodynamics of P sorption in three collected calcareous soil samples of east Azerbaijan province. Sorption kinetics was studied at 100 mg P L-1 solution as initial concentration before (B) and after (A) SOM removal and observations were carried out for 336 hours. SOM was removed with NaOCl solution. According to the results, P sorption increased rapidly up to about 48 hours beyond which a near steady-state condition was attained. Zero-order, first, second- and third-order equations did not adequately describe P sorption kinetics. Simple Elovich, parabolic diffusion and two-constant rate equations adequately described the data, but two-constant rate equation was the best. To evaluate the temperature effects, P sorption was measured at four temperatures, namely 10, 20, 30 and 400C. According to the results, P sorption, before and after SOM removal, increased with temperature raises indicating the endothermic nature of  the sorption reaction. The negative values of Gibbs free energy at different temperatures indicated the spontaneous nature of P sorption in the studied soils. Before SOM removal, ∆G0 in the first sorption site ranged from -32 to -38.2 kJ mol-1 and from -25.4 to -28.4 kJ mol-1 in the second site. While after the removal of organic matter in the first site ∆G0 ranged from -32.9 to -39.3 and in the second site from -30.9 to -36.9 kJ mol-1.