Colorimetric determination of pH
There is a need for a simple, rapid, reliable means for determining pH values of concentrated, high salt solutions without reliance on human eye and ambient light. The method comprises the steps of preparing a set of reference solutions, measuring the light absorption by each reference solution, adding indicator dye to each reference solution, measuring the light absorption by each such reference mixture, comparing the two solutions to determine the dye color at each pH, normalizing the spectra of mixture to the isosbestic point, and matching the color of the pH of the solution to one of the colors of the pHs in the reference solution set. In this way, the pH can be determined to within 0.1 pH unit, a far more precise method than using the human eye.
- Research Organization:
- Westinghouse Savannah River Co., Aiken, SC (United States)
- Sponsoring Organization:
- USDOE; USDOE, Washington, DC (United States)
- DOE Contract Number:
- AC09-89SR18035
- Assignee:
- Dept. of Energy
- Patent Number(s):
- PATENTS-US-A7681297
- Application Number:
- ON: DE93012027; PPN: US 7-681297
- OSTI ID:
- 6624203
- Resource Relation:
- Patent File Date: 8 Apr 1991
- Country of Publication:
- United States
- Language:
- English
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