Evaluation of a high-purity and high-stability continuous generation system for nitrous Acid

Autor: Roberto. Sparapani, Monica Gherardi, C. Perrino, A. Febo
Rok vydání: 2012
Předmět:
Zdroj: Environmental sciencetechnology. 29(9)
ISSN: 0013-936X
Popis: A flow-type system for the generation of nitrous acid in the mass flow rate range of 3.5-400 nmol/min is described. The system based on the reaction between gaseous hydrochloric acid, generated by means of a low-pressure permeation device, and solid sodium nitrite allows the continuous production of highly pure nitrous acid (purity >99.5%) and thus the generation of standard atmosphere in a very wide range of nitrous acid mixing ratio (5-20000 ppb). The system is of easy construction and exhibits a very high reproducibility and excellent long-term output stability. These features allow us to obtain any desired value of nitrous acid mass flow rate by simply tuning the temperature and flow rate values. As a consequence of the high purity of the generated compound, it was possible to obtain a clear absorption spectrum of nitrous acid without performing any correction for NO 2 interference.
Databáze: OpenAIRE