Colorimetric processes for the determination and control of the peracid content in a solution, in the presence of hydrogen peroxide
US5438002A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 1, 1991 |
| Grant date | Aug 1, 1995 |
| Priority date | — |
| Expiry date | Oct 1, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T436/206664
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The content of peracid, in the presence of hydrogen peroxide,in a solution 2 in which the molar ratio between the concentration of hydrogen peroxide and the concentration of peracid is not higher than 100, is adjusted by means of a process according to which the solution is drawn by a pump 3 into the suction circuits of two pumps 5, 6, which operate at the same flow rate and may draw simultaneously a dilution and /or pH control liquid 9. Pump 5 feeds the reference vat 7 of a two-beam photometer and pump 6 feeds the measuring vat 8, and the flow rates of the pumps 3, 5 and 6 are adjusted so that the concentration of peracid in the measuring flow 10 is lower than about 100 ppm by weight. An excess of iodide 11 is added to the measuring flow 10 which exits from the pump 6 by a pump 13 and measuring unit 14, to which are connected the cells of the photometer. The intensity of the iodine color formed in the measuring vat 8 is compared to the reference in the reference vat 7 and the difference is transferred to a regulator 16 which operates, if necessary, a pump 19 for the injection of the solution of peracid 20 into the solution 2.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.