【作者】 陈舟；

【导师】 张卫江；

【作者基本信息】 天津大学 ， 化学工程， 2005， 硕士

【摘要】 邻硝基甲苯是合成香料的主要原料,对硝基甲苯是合成药物及染料等中间体,它们都有着广泛的用途。对它们的分离一直以来都在研究,传统的方法有凝固点法、气相色谱法,但是分离效果均不理想。本文利用高效液相色谱法对邻硝基甲苯和对硝基甲苯两种同分异构体的分离作了系统的研究,确定了邻硝基甲苯和对硝基甲苯分离的最佳色谱条件。通过比较我们选择十八烷基键合相色谱柱,选择甲醇和水的混合物作为流动相。通过对水,甲醇水溶液和甲醇三种样品溶剂的溶解效果比较,选择甲醇作为样品溶剂。固定其他色谱条件,改变流动相组成分别为甲醇:水(V/V)=20:80; 30:70; 40:60; 50:50; 60:40; 70:30; 80:20,结果表明当甲醇:水=80:20的时候,分离度R达到2.44。可以实现基线分离。另一方面也考察了流速对分离效果的影响,分别取流速为0.8,0.9,1.0,1.1,1.2ml/min,结果表明随流速增大,保留值减小,提高了分析速度,但是随着流速增大,分离度较低,且柱压增大,不利于延长柱子的寿命。综合各种因素的影响,我们得到邻硝基甲苯和对硝基甲苯分离的最佳色谱条件为:甲醇:水=80:20(V/V)、检测波长278nm、流动相流速1.0ml/min、室温、色谱柱:COSMOSIL 5C18-AR-Ⅱ(6.0mm×250mm)。另外,本文对所建立的方法进行了回收率验证,结果显示该方法线性关系,准确度和灵敏度均符合分离要求。更多还原

【Abstract】 n-nitrotoluene is main material of synthetical spice. o-nitrotoluene is intermediate of synthetical medicine and dyestuff.They are both extensively used.The separation of them is studied all the while.Traditional methods include freezing point and gas chromatography,But the effect of separation is not so good. In this thesis,the separation of n-nitrotoluene and o-nitrotoluene is studied comprehensively by high-pressure liquid chromatography.The optimal conditions of separation are confirmed.By comparation we select C18 bonded-phase chromatography column and mixture of methanol and water as mobile phase.We choose methanol as solvent of specimen by comparing water, mixture of methanol and water and methanol.We set up methanol:water respectively as 20:80; 30:70; 40:60; 50:50; 60:40; 70:30:80:20(V/V)with the other conditions invariable.The result show that when methanol:water=80:20 base-line separation is obtained with a 2.44 resolution.On the other hand velocity of flow is investigate ed .we set up respectively velocity of flow as 0.8,0.9,1.0,1.1,1.2ml/min.The result are with velocity of flow increasing retention time minish but resolution diminish too. The best chromatogryphy conditions are methanol:water=80:20; detected wavelength is 278nm; velocity of flow is 1.0ml/min; room temperature; chromatogryphy column: COSMOSIL 5C18-AR-Ⅱ(6.0mm×250mm) In addition,the method is validated by recoveries experiment.The results show this method is reproducible and sensitive enough for separation of n-nitrotoluene and o-nitrotoluene.更多还原