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煤中氮含量的测定,一般文献上介紹的均为凱氏定氮法。該法虽經一再改良,但仍未能免除蒸餾手續。而一般文献上介紹的含氮化合物的凱氏定氮法等,也都需在消解后进行蒸餾。直至近年来才有免除蒸餾手續的改良凱氏定氮法。然而文献介紹的方法,其中所用的0.1N次溴酸鈉液,很不稳定;这样就使在常規分析时带来麻煩虼宋覀冇τ梦南诇y定硫酸銨中含氮量的原理,对煤中含氮量的測定方法,作了若干修改;在消解后直接滴定,免去蒸餾手續;这不但可节省时間及大量的氫氧化鈉;并可提高准确性。茲将修改后的方法詳述于下。
Determination of nitrogen in coal, the general literature are Kjeldahl method. Although the law has been repeatedly improved, but still can not be exempted from distillation procedures. The general literature describes the nitrogen-containing compounds such as Kjeldahl method, also need to be digested after distillation. Until recently, there was an improved Kjeldahl method for eliminating distillation procedures. However, the method described in the literature, in which the 0.1N sodium hypobromite solution used is very unstable, causes troubles in routine analysis. Therefore, the principle of determining the amount of nitrogen in ammonium sulfate Determination of nitrogen in coal, made a number of changes; after digestion in the direct titration, eliminating the need for distillation procedures; This will not only save time and a lot of sodium hydroxide; and can improve accuracy. The revised method will be described in detail below.