全自动流动注射-分光光度法测定土壤中氨氮

传统的氯化钾溶液提取分光光度法测定土壤中氨氮时,需要加入硝普钠-苯酚显色剂混匀后一定时间再加入二氯异氰尿酸钠显色剂,这个过程中人为接触苯酚等有机试剂的时间较长,对人体和环境有一定的危害;且传统的比色法显色时间至少需要5h,显色时间较长,分析效率较低.应用全自动流动注射-分光光度法测定土壤中氨氮,考察了提取试剂的厂家、浓...

Determination of Ammonia Nitrogen in Soil by Automatic Flow Injection-Spectrophotometry

This paper uses automatic flow injection-spectrophotometry analyzer to determine ammonia nitrogen in soil, a standard cu-rve of potassium chloride extract of 1.00 mol/L was prepared, the linear relationship is good in the linear range of 0~10.00 mg/L. The detection limit of the method is 0.031 mg/kg, the relative deviation of the sample is less than 5%, and the recovery rate of the actual sample is 89.0%-114%.In the traditional potassium chloride solution extraction spectrophotometric determination of ammonia nitrogen, it is necessary to add sodium nitroprusside-phenol chromogenic agent and mix it together for a certain time after adding sodium dichloroisocyanurate chromogenic agent, in this process, artificial exposure to phenol and other organic reagents for a long tim-e, which has a certain harm to the human body and the environment; Compared with the traditional spectrophotometric method of potassium chloride solution, automatic flow injection - spectrophotometry has the advantages of automatic sample entry, fast analysis rate, low reagent consumption, wide detection range and environmental protection, etc. This method is suitable for the detection of ammonia nitrogen in general agricultural land and site survey samples.