【作者】 杨泽玉；

【导师】 胡涌刚；

【作者基本信息】 华中科技大学 ， 环境科学， 2004， 硕士

【摘要】 化学发光法由于无需外加光源,避免了因瑞利散射和拉曼散射引起的背景噪音,因此灵敏度高,而且还具有线性范围宽、仪器设备简单、操作方便和容易实现自动化等诸多优点,基于其以上优点,本文初步结合手动注射-化学发光、流动注射-化学发光与毛细管电泳-化学发光等联用技术,应用于环境分析研究,扩大了化学发光法在环境分析中的应用范围,主要内容如下: (1)根据 Luminol-H2O2-Cr(Ⅲ)体系在碱性条件下产生很强的化学发光的原理,用光电二极管做检测器测定环境样品中的 Cr(Ⅲ)。本方法具有分析速度快、选择性好、检测装置结构非常简单,成本低等优点。其检测限为 5.0×10-8g/ml,线性范围为 5.0×10-8g/ml～5.0×10-4g/ml,相对标准偏差小于 5.0%。在实际样品的分析中,取得了令人满意的结果。 (2)根据重铬酸钾消解废水后其最终还原产物 Cr3+浓度与 COD 值成正比关系,以及在碱性条件下,Luminol-H2O2-Cr3+体系产生很强的化学发光的原理,提出了一种用光电二极管做检测器测定水体的化学需氧量的新方法。本方法线性范围为 2.1-600mg/L,r=0.9987;检出限为 2.1mg/L;回收率在 100±10%范围内;RSD≤5%(n=6)。用于实际样品测定,结果满意。本方法用于 COD 的测定,具有装置的结构简单、价格便宜、测定结果的精密度和准确度均较好、适用于多种废水 COD 的测定等优点。如果将本方法与微波消解以及流动注射方法联用,将为开发一种快速、准确而又结构简单的 COD 自动在线监测仪开辟一条全新的途径。 (3)基于 4-(2-呲啶偶氮)-间苯二酚(PAR)在碱性条件下催化铁氰化钾-鲁米诺体系产生很强的化学发光的原理,对影响 PAR 发光的条件进行了优化选择,得出该体系下,PAR 的相对标准偏差为 2.7%,线性范围为 1.0×10-5 mol/L～1.0×10-7 mol/L;检测限为 5.7×10-8mol/L。利用 PAR 对许多金属离子的络合性,得出测定某些金属离子的检测限,这样一方面建立了测定 PAR 的化学发光新方法,另一方面为色谱或毛细管电泳等分离技术在金属离子的分析方面展示了一种新颖的方法前景。 (4)基于铁氰化钾在存放过程中微弱水解成氰化钾,以及 Cu2+在 CN-存在下,与鲁米诺相偶合反应形成 Cu(CN)2 络合物产生化学发光的原理,建立了一种新的测定痕 -量铜的化学发光方法,其相对标准偏差小于5.0% ;线性范围为1.0×10-7 mol/L-5.0 ×10-9 mol/L,r=0.9904;检测限(S/N=3)为 8.0×10-10 mol/L,该灵敏度与用 KCN-Luminol体系测定铜相当。但众所周知,KCN 有剧毒,不易获得,本方法利用 K3[Fe(CN)]6代 I<WP=5>替 KCN,一方面大大降低了由于 KCN 引起的毒性,另一方面 K3[Fe(CN)]6较 KCN 更易获得。并成功地实现了对环境样品中痕量铜的定量分析。(5)基于碱性条件下,酚类物质淬灭铁氰化钾-鲁米诺体系发光的原理,利用毛细管电泳-化学发光技术分离并测定了三种苯二酚异构体及苯酚,探讨了其最佳发光实验条件及最佳分离条件,得出在该条件下,对苯二酚、间苯二酚、邻苯二酚及苯酚的质量检测限分别为:16.36amol、187.59amol、60.96amol 及 1822.5amol; 浓度检测限分别为:3.2×10-8, 8.6×10-8, 3.9×10-7 及 4.5×10-6mol/L。其中对对苯二酚与邻苯二酚的检测灵敏度与毛细管电泳-电化学检测系统相当。而且该化学发光系统的最大优点是不必担心由于过氧化氢的引入而引起的气泡的问题。而且该检测方法简单,避免了繁锁的柱前、柱后衍生步骤并且不需要催化剂。更多还原

【Abstract】 Chemiluminescene(CL) is highly sensitive. It needs no exciting light source, and thus isnot accompanied with any scattering light from it. This permits an increase of sensitivity ina detector, and therefore an attainment of a large signal-to-noise ratio (S/N). Besides, thereare more advantages in CL detection, such as wide dynamic range, simple instrumentation,versatility of use and the easy automation. The method that is one of the studied focus in thearea of analytical chemistry today has gained wide use in environmental, pharmaceuticaland biological analysis. Based on its advantages, here we combined the detection method with mauley injectiontechnique, flow injection (FI) technique and capillary electrophoresis(CE) technique, furtherto extend its application in environmental analysis. The main contents are shown as follows: (1)Anovel, simple analytical procedure for determination of Chromium(Ⅲ) in environmental samples with photodiode detector is presented successfully, which isbased on the fact that chromium(Ⅲ) can catalyze the luminol oxidation reaction withhydrogen peroxide in basic medium using potassium bromide as an enhancer .The singleanalyzing time is less than 1 min. The linear range of calibration curve was 5.0×10-8g/ml～5.0×10-4g/ml . The detection limit was 5.0×10-8g/ml . The RSD was less than 5.0%(n=6).And the detecting equipment is simple and cheap. The method has been applied to thedetermination of Cr(Ⅲ) in environmental samples successfully . (2) Based on the chemiluminescent reaction of luminol-H2O2-Cr3+ system, lightemission caused by luminol-H2O2-Cr3+system was detected by the photodiode, and itsintensity caused by the appearance of Cr3+after samples digestion was proportional to thechemical oxygen demand. A low cost chemiluminescence detector with a photodiodeinstead of photo-multiplier tube (PMT) was developed for environmental monitoring ofwater quality. The linear range was 2.1～600mg/L, r=0.9987; recovery rate was between90% and 110% and RSD was lower than 5.0%(n=6). The experimental results show that thissuggested method uses an instrument simpler and cheaper than the previous ones for thesame purpose. The data obtained by the present method were fairly in good agreement withthose obtained by the standard reflux titrimetric method. It has been applied to determinereal samples with satisfactory results. If combined the present method with microwave III<WP=7>digestion and flow injection, a novel way to can be pioneered to develop a fast, accurate andsimple COD automation detection instrument. (3) PAR showed intensive chemiluminescence (CL) when it was added to thelumonol-K3Fe(CN)6 system in the NaOH basic medium. The main factors that affected theCL reaction were examined. A new analytical method for determination of schiff base withAzosubstituted groups was proposed. The linear relationship between the intensity of CLand the concentration of PAR was in the range of 1.0×10-5 mol/L～1.0×10-7 mol/L ,andthe detection of limit was 5.7×10-8mol/L,the RSD was 2.7%.Beacuse PAR is a commonlychelating agent in the analysis of many metal ions, the method has also been used todetermine several metal ions according to the decrease of relative chemiluminescenceintensity of PAR and the detection of limit of these metal ions were acquired, so the studyalso afforded a new prospect for the analysis of metal ions using chromatography orcapillary electrophoresis. (4) According to the fact that potassium ferricyanide hydrolyzes to form KCN, andCu2+ reacts with luminol forming Cu (CN)2 to generate luminescence. A new method for -the determination of Cu2+ in environmental samples was studied. The linear range was 1.0×10-7 mol/L～5.0 ×10-9 mol/L ,the limited detection was 8.06×10-10 mol/L ,the RSD was3.0%(n=6). The acquired limited detection was corresponded to that of KCN-Luminolsystem. But it is well know更多还原