A rapid automated system for the analysis of dissolved total organic nitrogen in aqueous solutions

Abstract

An automated system for the analysis of dissolved organic nitrogen has been developed and applied to natural waters. It is based on subjecting sample to u.v. irradiation followed by a heterogeneous reduction of the nitrogen containing irradiation products to ammonia which is detected by an ammonia gas sensing probe. Quantitative recoveries of different organic nitrogen compounds common to natural waters were obtained after 17 rain of irradiation. Determination with and without irradiation make possible the separate determination of total and inorganic nitrogen, respectively.

Mineral constituents

“…Moreover, the pH value allows the specific reactivity of organic and i n o r g a n i cn i t r o g e n .T h ep He f f e c tc a nb es t u d i e df r o mt h ec o m p a r i s o no f the photooxidation of urea (as organic nitrogen) and ammonium chloride (as inorganic nitrogen). It appears that the conversion of urea is weakly modified by the pH and varies between 80% and 95%, whatever the pH value, whereas the conversion yield from the ammonium nitrogen is very weak in acidic medium and becomes quantitative for basic conditions [31].…”