Photochemistry of nitrite and nitrate in aqueous solution: a review

TLDR: A review of the experimental work on NO2− and NO3− photolysis in the context of recent advances in the understanding of the chemistry of the peroxynitrite anion (ONOO−) in biological experiments is presented in this article.

Abstract: It has long been known that the photolysis of nitrite and nitrate solutions results in the formation of OH radicals. The mechanism of NO3− photolysis has been the subject of considerable controversy in the literature, however. This review summarizes the experimental work on NO2− and NO3− photolysis in the context of recent advances in the understanding of the chemistry of the peroxynitrite anion (ONOO−) in biological experiments. ONOO− has been found to play a far more significant role in the overall reaction mechanism of NO3− photolysis than had previously been suspected. Research on NO2− and NO3− photolysis, as a pathway to the destruction of organic contaminants in natural waters, is summarized. The possible impact of NO2− and NO3− on Advanced Oxidation Technologies (AOTs), in which OH radicals are used to initiate the destruction of hazardous organic pollutants in drinking water and industrial waste streams, is explored.