کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
4486445 | 1316989 | 2006 | 9 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Bio-reduction of soluble chromate using a hydrogen-based membrane biofilm reactor Bio-reduction of soluble chromate using a hydrogen-based membrane biofilm reactor](/preview/png/4486445.png)
Hexavalent chromium (Cr(VI)) is a mutagen and carcinogen that is a significant concern in water and wastewater. A simple and non-hazardous means to remove Cr(VI) is bioreduction to Cr(III), which should precipitate as Cr(OH)3(s). Since Cr(VI)-reducing bacteria can use hydrogen (H2) as an electron donor, we tested the potential of the H2-based membrane biofilm reactor (MBfR) for chromate reduction and removal from water and wastewater. When Cr(VI) was added to a denitrifying MBfR, Cr(VI) reduction was immediate and increased over 11 days. Short-term experiments investigated the effects of Cr(VI) loading, H2 pressure, and nitrate loading on Cr(VI) reduction. Increasing the H2 pressure improved Cr(VI) reduction. Cr(VI) reduction also was sensitive to pH, with an optimum near 7.0, a sharp drop off below 7.0, and a gradual decline to 8.2. Cr(III) precipitated after a small upward adjustment of the pH. These experiments confirm that a denitrifying, H2-based MBfR can be used to reduce Cr(VI) to Cr(III) and remove Cr from water. The research shows that critical operational parameters include the H2 concentration, nitrate concentration, and pH.
Journal: Water Research - Volume 40, Issue 8, May 2006, Pages 1634–1642