Kinetic Study of Redox Processes of Chromium in Natural River Water

نویسنده

  • R. Świetlik
چکیده

Chromium contamination in the area of the Radomka river basin in Poland has lead to significant environmental problems. Therefore, chromium redox transformations were investigated in the aquatic environment under conditions as close to natural as possible at intermediate pH and in the presence of original bottom sediment and dissolved oxygen. Reduction of Cr(VI) in the Radomka river water occurs at a low rate (t1/2 = 19 h). The rate of Cr(VI) reduction increased in the river water spiked by HA (t1/2 = 0.5 h), and Fe(II) (t1/2 = 2 min). The kinetics of Cr(VI) reduction by Fe(II) was dependent on the evolution of the forms of Cr(VI) and the competing Fe(II) oxidation reaction by dissolved oxygen. The reduction of Cr(VI) by humic acids appeared to be a significantly slower process than Fe(II) oxidation by O2. Chromium(III) present in the tanning liquor used and the aged solution of chromium sulphate was less prone to oxidation by MnO2 than Cr(III) introduced with chromium nitrate and sulphate solutions (7% and 10% conversion over 1 h in comparison with 55% and 32%, respectively). Chromium deposits in bottom sediment turned out to be resistant to oxidation by MnO2.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Rapid Determination of Chromium (M)lli Natural Water and Industrial Effluents Using Kinetic Speetrophotometric Method

A new simple arid rapid catalytic kinetic method for determination of trace amounts of chromium (110 isdescribed. The method is based on the catalytic effect of chromium (III) on the reduction of Methylene blue byascorbic acid in acidic media. The reaction monitored smectrophotomenically by measuring the decrease ofabsorbance at 664 nm at 25 C. The fixed-time method was used for the first 300 s...

متن کامل

Seasonal Variations of Lead and Chromium Concentrations in the Water Samples From Yamuna River in Delhi, India

Background: According to Hindu mythology, Yamuna River plays an impotent role as a holy water resource in Delhi, India. The lead and chromium concentrations were determined from the water samples collected from five different locations around this river in Delhi area. The contaminated water from this river is mostly used for drinking, agriculture, aquaculture, and storage as a holy water. Meth...

متن کامل

Study Concentrations Changes of Lead, Chromium, Nickel, Cadmium, Zinc and Copper in Beshar River of Kohgiluyeh and Boyerahmad Province, Iran

Due to the lack of water quality of resourses in country, exact review of available water resources quality, especially in terms of heavy elements (heavy metals) has a particular importance. Due to industrial towns 1 and 2 of Yasuj city and also Yasuj wastewater treatment, surveying environmental harmful effects of heavy metals on this river is very important. To investigate the changes of heav...

متن کامل

Role of estuarine natural processes in removal of trace metals under emergency situations

Estuaries are well known for their potential in removing metal from fresh water to provide micro-nutrients to aquatic life. In the present investigation, we have tried to bring out the metal removal potential of estuaries during accidental spills. For this purpose artificial river water containing high concentration of Mn, Cu, Zn, Ni and Pb were mixed with sea water at different salinity regime...

متن کامل

Role of estuarine natural flocculation process in removal of Cu, Mn, Ni, Pb and Zn

The flocculation of dissolved heavy metals is a process which has an important effect on decreasing the concentration of the colloidal elements during estuarine mixing of river water and sea or ocean water. During this important process, a large amount of colloidal elements change into particles in the form of flock and the dissolved loads decline. This study is performed to evaluate the mechani...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2006