Estimating iron and aluminum content of acid mine discharge from a north-central Pennsylvania coal field by use of acidity titration curves
Water-Resources Investigations Report
84-4335
By: A.N. Ott
Links
- Document: Report (pdf)
- Download citation as: RIS | Dublin Core
Abstract
Determination of acidity provides a value that denotes the quantitative capacity of the sample water to neutralize a strong base to a particular pH. However, much additional information can be obtained from this determination if a titration curve is constructed from recorded data of titrant increments and their corresponding pH values. The curve can be used to identify buffer capabilities, the acidity with respect to any pH value within the curve limit, and, in the case of acid mine drainage from north-central Pennsylvania, the identification and estimation of the concentration of dissolved ferrous iron, ferric iron, and aluminum.
Through use of titration curves, a relationship was observed for the acid mine drainage between: (1) the titratable acidity (as milligrams per liter calcium carbonate) to pH 4.0 and the concentration of dissolved ferric iron; and (2) the titratable acidity (as milligrams per liter calcium carbonate) from pH 4.0 to 5.0 and the concentration of dissolved aluminum. The presence of dissolved ferrous iron can be detected by the buffering effect exhibited in the area between pH 5.5 to 7.5. The concentration of ferrous iron is estimated by difference between the concentrations of ferric iron in an oxidized and unoxidized sample. Interferences in any of the titrations from manganese, magnesium, and aluminate, appear to be negligible within the pH range of interest.
Suggested Citation
Ott, A., 1986, Estimating iron and aluminum content of acid mine discharge from a north-central Pennsylvania coal field by use of acidity titration curves: U.S. Geological Survey Water-Resources Investigations Report 84-4335, iv, 25 p. :ill. ;28 cm., https://doi.org/10.3133/wri844335.
| Publication type | Report |
|---|---|
| Publication Subtype | USGS Numbered Series |
| Title | Estimating iron and aluminum content of acid mine discharge from a north-central Pennsylvania coal field by use of acidity titration curves |
| Series title | Water-Resources Investigations Report |
| Series number | 84-4335 |
| DOI | 10.3133/wri844335 |
| Year Published | 1986 |
| Language | English |
| Publisher | U.S. Geological Survey |
| Contributing office(s) | Pennsylvania Water Science Center |
| Description | iv, 25 p. :ill. ;28 cm. |