| Main Title |
The fate of chromium (III) in chlorinated water / |
| Author |
Clifford, Dennis A. ;
Chau, J. M.
|
| Other Authors |
|
| CORP Author |
Houston Univ., TX. Dept. of Civil Engineering.;Environmental Protection Agency, Cincinnati, OH. Water Engineering Research Lab. |
| Publisher |
U.S. Environmental Protection Agency, Water Engineering Research Laboratory, |
| Year Published |
1987 |
| Report Number |
EPA-R-807939; EPA/600/2-87/100 |
| Stock Number |
PB88-130992 |
| Subjects |
Chromium ;
Water--Purification--Chlorination
|
| Additional Subjects |
Water analysis ;
Chlorination ;
Chemical properties ;
Oxidation ;
Chemical analysis ;
Water pollution detection
|
| Holdings |
| Library |
Call Number |
Additional Info |
Location |
Last
Modified |
Checkout
Status |
| NTIS |
PB88-130992 |
Some EPA libraries have a fiche copy filed under the call number shown. |
|
07/26/2022 |
|
| Collation |
74 pages : illustrations ; 28 cm |
| Abstract |
The oxidation of trivalent chromium, Cr(III), to the more toxic Cr(VI) in chlorinated water is thermodynamically feasible and was the subject of the study. The study found that free available chlorine (FAC) readily converts Cr(III) to Cr(VI) at a rate that is highly dependent upon pH, total organic carbon (TOC), and chloride concentrations while combined chlorine (CAC) does not oxidize Cr(III). The highest oxidation rate occurs in the 5.5-6.0 pH range. The aquatic humus in natural water, however, inhibits while chloride concentration catalyzes the rate of Cr(VI) formation. As expected, the initial Cr(III) oxidation rate increased with increasing FAC concentration and Cr(III) level. Monochloramine, a form of CAC, did not oxidize Cr(III) at any tested pH between 6 and 8.5. The results suggest that the oxidation of Cr(III) and Cr(VI) would rarely occur to a significant extent during drinking water chlorination because of the presence of naturally occurring organics (TOC), the low concentrations of Cr(III) in natural waters, and the probable removal of insoluble Cr(OH)3 during coagulation. However, in CR(III)-contaminated waters that are relatively free of organic contamination and have pH's in the 5-7 range, FAC readily converts Cr(III) to the more toxic hexavalent variety. |
| Notes |
"Nov. 1987." "EPA/600/2-87/100." Microfiche. |
| Place Published |
Cincinnati, OH : |
| Supplementary Notes |
Sponsored by Environmental Protection Agency, Cincinnati, OH. Water Engineering Research Lab. |
| Corporate Au Added Ent |
Water Engineering Research Laboratory. |
| PUB Date Free Form |
{1988} |
| NTIS Prices |
PC A04/MF A01 |
| BIB Level |
m |
| Cataloging Source |
OCLC/T |
| OCLC Time Stamp |
20020117183514 |
| Language |
eng |
| Origin |
NTIS |
| Type |
MERGE |
| OCLC Rec Leader |
00964nam 2200265Ka 45020 |
