An Analysis on the Cause of Reddish Black Impurities Created in Digestion Pool of an Online Unit of Non-Standardized Resorcinol Method for the Determination of Total Nitrogen in Water
Existing issues in the online determination of total nitrogen content in water by a non-standardized resorcinol method were studied.It has found that reddish black impurities could be created in the digestion pool so as to cause a bit higher measuring results.Through an analysis on the reaction principles and any possible secondary reactions,the primary source of the reddish black impurities was inferred to be a complex reaction between resorcinol and Fe(Ⅲ)that has been verified by conducting experiments.To eliminate the interference,it is suggested to use more purified sulphuric acid whilst regularly demounting and cleaning the digestion pool.
Determination of total nitrogenResorcinolReddish black impurity
NETL
NSTL
万方数据
