痕量亚硝酸根的快速萃取-比色测定.pdf

第45卷第3期
应用化工
Vol 45 No. 3
2016年3月
Applied Chemical Industry
Mar.2016
痕量亚硝酸根的快速萃取-比色测定
刘国霞,张海霞,张新
(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)
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3.0mL,硫酸铵用量2.5g,亚硝酸根的显色产物被苯取到聚乙二醇相,最大吸收波长为540nm。亚硝酸根在
2.0~80pg/L浓度范围内与吸光度呈线性关系,相关系数为0.9924,方法的检出限为1.07ug/L,对于质量浓度
为5.0pg/L和50.0Hg/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%。
关键词:痕量亚硝酸根;双水相萃取;比色法
中图分类号:TQ126;0657.3;0658.2文献标识码:A文章编号:1671-3206(2016)03-0557-04
Rapid determination of trace nitrite ion by
extraction and colorimetric method
L Go-ia ZHANG Hai-xia AANG Xin
1. Department of Chemical Engineering, Binzhou University, Binzhou 256603, China;
2. Key Laboratory for Comprehensive Utilization of Liquid Pollutants of Binzhou City, Binzhou 256603, China)
Abstract A method for rapid determination of trace nitrite ion by colorimetry coupled with two-phase
aqueous extraction was developed. With sul anilin acid and N-(1-naphthyl)ethylenediamine hydrochlo-
ride as reagent, polyethylene glycol (PEG) -6000 as extraction solvent and ammonium sulfate as salting
out agent. Various conditions that affect phase separation were optimized. The complex of nitrite ion was
extraced in o he upper Peg-ich phase when the volume of PEG-6000 3.0 ML and the quality of ammo-
nium sulate 2. 5 6, 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 concentra
tion in the range of 20-80 H/ with the correlation coefficient of 0.999 24. The detection limit of this
method was 1.07 wg/L. The RSD was 3.09% and 2. 47% for ten times of determination of a sample with
nitrite ion content of 5.0 wg/L and 50.0 wg/L. This method has been applied to the determination of ni
trite ion in water samples with the recovery of.4%102. 1%
ro-phase aqu
thod
亚硝酸盐因在食品、纺织、电镀、建筑等行业的现场快速分析,是目前国内外检测亚硝酸根的主要
应用而广泛存在于与生命密切相关的食品及天然水方法,但由于灵敏度不高,难以实现痕量亚硝酸根的
中。目前,测定亚硝酸根的方法有比色法( Griess检测。尽管文献报道了几种萃取富集亚硝酸根的方
法)叫、荧光猝灭法?、流动注射法]、电化学方法,如分散液液微萃取?、微晶酚酞分散固相萃
法?、离子色谱法?等。后几种方法所用仪器价格取?、浊点萃取?,但分散液液微萃取和微晶酚酞
昂贵、运行费用高,且操作复杂不能进行快速检测。分散固相萃取分别使用大量对人体及环境有毒的四
比色法设备简单、操作方便、便于携带,特别适用于氯化碳和酚酞,浊点萃取需要在非室温条件下
收稿日期:2015-02-14
基金项目:滨州市科学技术发展计划(软科学部分)项目(2014RKXI2);滨州市科学技术发展计划(政策引导类)项目
(2014Z0302);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(BZX
作者简介:刘国霞(1982-),女,山东滨州人,滨州学院讲师,硕士,主要从事痕量物质的富集与测定研究。电话:
13954370676,E-mail:liuguoxialgx@163.com