预蒸馏-纳氏试剂分光光度法测定水样中氨氮的优化

The Optimization of Determination of Amonia Nitrogen in Water by Predistillation-nessler’s Reagent Spectrophotometer

由于硼酸吸收液的影响,按照国家标准HJ 535-2009,使用预蒸馏法对水样进行前处理时,氨氮实测结果偏低。用无氨水代替硼酸作为吸收液,从而消除硼酸对氨氮测定的影响。探讨了无氨水作为吸收液时的吸收效率;对预蒸馏水样的保存时间进行了实验研究。实验结果表明,使用无氨水作为吸收液,具有很好的准确度和精密度,并且简化了实验操作过程。

According to national standard (HJ 535-2009),predistillation was used in the pretreatment of water.Because of the effect of boric acid absorption liquid,the determining result of amonia nitrogen was low.When non-ammonia water was used as absorption liquid,the effect was eliminated.The absorption efficiency of non-ammonia water was discussed.The preservative time of pre-distilled water sample was researched.The results show that the method has good precision and accuracy,and simple operation.