The Study And Application Of Chromatographic Analysis In The Process Of Chemical Engineering

This paper is part of task of Hunan province science and technology tackling key project. According to the requirement of the trial, chromatographic analysis has been studied in the key project involved medicine, pesticide and petrochemical industry emphatically.This paper consists of three chapters:In Chapter 1 ,the separating and determining of organic acids from the process of waste alkali water from the oxidation of cyclohexane has been studied. Waste alkali water from the oxidation of cyclohexane is the side product of cyclohexane oxidating in the process of producing caprolactam, which is very complex. According to the properties of samples,a capillary gas chromatography is described for separating and determining various carboxylic acid .Waste lye is oxidized, centrifuged, acidified and pumping filtrated .The separating condition is strong polarity PEG(20M) capillary column treated by procedure temperature, acetone solvent, propanoic acid as internal material .The linear range of acetic acid, propanoic acid, pentanoic acid , hexanooic acid is 0.01~ 0.4, 0.02 ~ 0.8, 0.02 - 0.6, 0.02~0.5g/L respectively, correlation coefficient is 0.9992, 0.9988, 0.9986, 0.9990 respectively. The relative deviations are less than 2.2%(n=5),and in every sample the recoveries are85%~105%.The separation and determination of organic acids from the process of cyclohexane oxidation in waste alkali water is described by reverse-phase high performance liquid chromatography. The operating conditions are: YWG-C18 column (10μm,4.6mm i.d. X 25cm) at 25℃, 20 mmol/L phosphoric acids buffer solution (pH=2.30)and methanol as mobile phase at a flow rate of 1 .0mL/min and UV detector at 210 nm. The linear range of pentanoic acid , hexanoic acid, succinic acid,pentanedioic acid, hexanedioic acid is 2.00-20.00, 2.12-21.20, 1.97-19.70, 2.00~20.00, 2.50-35.00 g/L respectively, correlation coefficient is 0.9986,0.9988,0.9992,0.9986,0.9988 respectively. The relative standard deviations are less than 1.5% and the recoveries are 95.5%~103.2%.In Chapter 2, the separation and determination of the synthesis product butenafine and related materials are investigated by reverse-phase high-performance liquid chromatography in detail .The separating conditions are: SS Exile ODS (150 X 4.6mm, 10m)as column, MeOH-H2O-(C2H5)3 N (85:13:2,V/V) as mobile phase ,UV detector (254nm)and a flow rate at 1.5mL/min.The linear range is from 0.2 g/L to 2.0 g/L, correlation coefficient is 0.9986.The average recovery of the method was 98.5% and the RSD is 1.8% (n=5).The coefficient of variation was less than 2%.The method is simple , rapid, accurate and has been successfully applied to determine butenafine of the complex system in the process of synthesis .In Chapter 3, a method for determination of biotics pesticide 2,3-dichloro-N,N-dimethylpropyl-amine hydrochloride in aqueous has been developed by capillary gas chromatography in detail .The method has been brought forward under the condition of national standard method (GB8200-87) existing the problem of accuracy .The samples are neutralized by sodium hydroxide and extracted by trichloromethane. Toluene is used as the internal standard. The separating conditions are : column AC 1 fused silica capillary column(30mx0.32mm i.d.),consisted of 100% dimethyl-polysiloxane, the temperature of the column, injector and the detector are 115℃,160℃,and 160℃ respectively. Carrier gas (N2) pressure: 16 psig; range: 20; Attenuation: 2; injection volume: lL.The relative standard deviation was less than 2.0% and the recovery of the method is in the range of 96.6%~103.6%.The method is simple,rapid, accurate and reproducible, making up the short of national standard method.In a word, we have established several new systems for analyzing the samples of chemical process. The method was convenient ,simple and accurate which laid good foundation for finishing Hunan province science and technology tackling key project.