杜马斯燃烧定氮法测定复混肥料中的总氮

Determination of total nitrogen content in mixed fertilizer by Dumas combustion method

应用杜马斯燃烧定氮法对各类含不同型态氮的复混肥料中的总氮含量进行了测定。结果表明,该方法的相对标准偏差(RSD%)为:0.15%~0.45%,与国标GB/T8572-2010方法比较^([1]),同一样品测量重复性在0.02%~0.10%之间,均低于于国标方法规定的限值(≤0.30%)。对不同样品进行检验,结果与国标方法所得结果差异不显著(p>0.05),加标回收率为:98.7%~99.2%.表明该方法可进行复混肥料中氮含量的测定。

The results show that the relative standard deviation of the method （RSD%） is 0.15% -0.45%, compared with the standard GB/T8572-2010, the same sample measurement repeatability in 0.02%-0.10% is lower than the limits specified in the national standard method（less than 0.30%）, the rate of recovery is 98.7 %-99.2 %. The method can be used to determine the content of nitrogen in complex mixed fertilizer.