On-site manufacture of ultra-high-purity nitric acid
US6214173A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 5, 1996 |
| Grant date | Apr 10, 2001 |
| Priority date | — |
| Expiry date | Dec 5, 2016 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01D3/34
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Provided is a novel on-site system and method for providing ultra-high-purity nitric acid to a point of use. The system includes a source of nitric acid at a concentration greater than 68 wt %; a reflux distillation column having an inlet in communication with the nitric acid source for introducing nitric acid into the column, a reboiler, and a condensate outlet to provide a flow of nitric acid condensate from the column; a reservoir in communication with the condensate outlet for receiving the flow of nitric acid condensate; and piping for delivering nitric acid from the reservoir to a point of use. The system and method can be used as an on-site subsystem, in a semiconductor device fabrication facility for supplying the nitric acid condensate to points of use in the semiconductor device fabrication facility.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.