痕量亚硝酸根的快速萃取-比色测定  

Rapid determination of trace nitrite ion by extraction and colorimetric method

作　　者：刘国霞[1,2] 张海霞[1,2] 张新[1,2] 

机构地区：[1]滨州学院化学工程系,山东滨州256603 [2]滨州市液态污染物综合利用技术重点实验室,山东滨州256603

出　　处：《应用化工》2016年第3期557-560,共4页Applied Chemical Industry

基　　金：滨州市科学技术发展计划(软科学部分)项目(2014RKX12);滨州市科学技术发展计划(政策引导类)项目(2014ZC0302);滨州学院服务滨州科学发展行动计划项目(BZXYFB20120602);滨州学院科研基金项目(BZXYG1406)

摘　　要：以对氨基苯磺酸和盐酸萘乙二胺为显色剂,聚乙二醇6000为萃取剂,硫酸铵为盐析剂,建立了双水相萃取-比色法快速测定痕量亚硝酸根的分析方法,并对影响相分离的各种条件进行了优化。结果表明,当聚乙二醇6000用量3.0 m L,硫酸铵用量2.5 g,亚硝酸根的显色产物被萃取到聚乙二醇相,最大吸收波长为540 nm。亚硝酸根在2.0-80μg/L浓度范围内与吸光度呈线性关系,相关系数为0.999 24,方法的检出限为1.07μg/L,对于质量浓度为5.0μg/L和50.0μg/L的亚硝酸根进行10次反复测量,得到其相对标准偏差分别为3.09%和2.47%。该方法用于水样中亚硝酸根的测定,回收率为98.4%-102.1%。A method for rapid determination of trace nitrite ion by colorimetry coupled with two-phase aqueous extraction was developed. With sulfanilic acid and N-（ 1-naphthyl） ethylenediamine dihydrochloride as reagent,polyethylene glycol（ PEG）-6000 as extraction solvent and ammonium sulfate as saltingout agent. Various conditions that affect phase separation were optimized. The complex of nitrite ion was extracted into the upper PEG-rich phase when the volume of PEG-6000 3. 0 m L and the quality of ammonium sulfate 2. 5 g,the maximum absorption peak of the extracted complex in the upper PEG-rich phase was located at 540 nm. There was a linear relationship between absorbance and nitrite ion mass concentration in the range of 2. 0 - 80 μg / L with the correlation coefficient of 0. 999 24. The detection limit of this method was 1. 07 μg / L. The RSD was 3. 09% and 2. 47% for ten times of determination of a sample with nitrite ion content of 5. 0 μg / L and 50. 0 μg / L. This method has been applied to the determination of nitrite ion in water samples with the recovery of 98. 4% - 102. 1%.

关 键 词：痕量亚硝酸根 双水相萃取 比色法 

分 类 号：TQ126[化学工程—无机化工] O657.3[理学—分析化学]