Investigation of organic and mineral variation of Fe, Mn with temperature, pH and alkalinity in water

Subject Areas : environmental management

Seyyed mostafa khezri khezri ¹ , Alireza Rahmani Rahmani ² , mohamad Taghei samadi ³ , vahid Hayatbakhsh malayeri ⁴

1 - دانشیار، دانشکده محیط زیست و انرژی، واحد علوم و تحقیقات دانشگاه آزاد اسلامی تهران *(مسئول مکاتبات)
2 - عضور هیات علمی دانشکده بهداشت، دانشگاه علوم پزشکی همدان
3 - عضور هیات علمی دانشکده بهداشت، دانشگاه علوم پزشکی همدان
4 - دانش آموخته دوره کارشناسی ارشد رشته مهندسی محیط زیست، دانشکده محیط زیست و انرژی، دانشگاه آزاد اسلامی، واحد علوم و تحقیقات، تهران*(مسئول مکاتبات)

Received: 2008-11-19 Accepted : 2009-06-28 Published : 2012-12-21

Keywords: alkalinity, temperature, digestion, Mn&amp, Fe,

Abstract :

A little amount of Fe and Mn in drinking and industrial water cause many problems. In river and surface water system, these metals distributed between solute and solid phase (volatile and sediment), that considering different situation, the distribution and exchange of these metals is not in uniform shape. Temperature, pH and alkalinity are the main factors in exchange of these metals between mentioned phases. This research aim is to investigate the variation of factors with mineral and organic compound of Fe and Mn. In this research solution with concentration of 10 mg/L of sulphat and acetat iron and 2mg/L of sulphat and acetate Mn were utilized. The proceed include the preparation of solutions, investigation the impact of pH, Alkalinity and temperature, which the solubility of these mineral and organic compound of Fe and Mn was investigated in pH of 6 to 12, alkalinity of 50 up to 400 and temperature 0 to 35 ,respectively. The results were investigated after digestion of metals in the solution and was applied the atomic absorption device. Increase of alkalinity has more effect on the iron sulphate reduction which the minimum solution in alkalinity of 400 is about 0.486mg/L. Increase of pH has the most effect on the solution reduction of iron acetate that the minimum solution is happen in pH=12 and equals 0.441.Meanwhile, increase of pH has the most effect on the solution of sulphate and Mn acetate which minimum solution in pH=12 are respectively as 0.247 and 0.372 .By increasing the  temperature, the solution is reduced that this reduction is high in Mn value than Fe compound and also is more than in mineral compound than organic compound. In addition, in total experiment about 90% Mn was soluble in water while the maximum solubility of iron was about40%.