An Improved Method for Determining Total Nitrogen in Soil by Kjeldahl Distillation
The Kjeldahl distillation method was used to determine total nitrogen in soil for nine different types of soil.Through experimental data comparison of different reducing agents,catalysts,and oxidants,it was found that using sodium thiosulfate pentahydrate as a reducing agent,K2SO4+CuSO4+TiO2 as a catalyst,and sulfuric acid as an oxidant has the advantages of simple operation,time-saving,and pollution-free.This method corresponds to a recovery rate of 88.9%to 93.1%for different types of soil,a relative error of 0%for standard sample testing,a standard deviation of 8.1%to 16.5%,and a detection limit of 14 mg/kg.
Kjeldahl Distillationsoil total nitrogendifferent types of soil
NETL
NSTL
万方数据
