Determination Of Nitrosamines In Several Typical Nitrogen-containing Surfactants

The qualitative and quantitative analysis of nitrosamines in nitrogenous surfactants was carried out by using different experimental methods in this thesis.The main research works are outlined as follows:A new qualitative method for N-nitrosamines was established,and two different experimental methods of water-bath decomposition and ultraviolet decomposition were set up.21 kinds of washing samples sold in the market were analyzed by ultraviolet decomposition method,and 13 of them detected to N-nitrosamines.The experimental method is simple,easy to operate,and can be used for qualitative analysis of N-nitrosamines.A method of high performance liquid chromatography-diode array detector(HPLC-DAD)was set up to detect N-nitrosodiethanolamine(NDELA)in cocoic acid monoethanolamide(CMEA)and cocoic acid diethanolamide(CDEA).The wavelength of UV detection was 233 nm,The results showed that at the selected conditions,the N-nitrosodiethanolamine in coconut monoethanolamide and coconut diethanolamide could be qualitatively and quantitatively analyzed.The limit of detection and the limit of quantitation were 15 μg/L,48 μg/L,spiked recovery were 94.5%~98.5%,relative standard deviation(RSD)were 2.6%~7.4%,this method is simple,rapid,and reproducible.It is suitable for the determination of N-nitrosodiethanolamine in general surfactants.A method for the determination of N-nitrosodiethanolamine(NDELA)in coconut oil amide propyl betaine(CAB),coconut diethanolamide(CDEA)and castor oil acylthreonine sodium by high performance liquid chromatography-variable wavelength scanning ultraviolet detector(HPLC-VWD)was established.The wavelength of ultraviolet detection is 234 nm.Under the selected experimental conditions,N-nitrosodiethanolamine in three surfactants can be qualitatively and quantitatively analyzed.The detection limit and quantification limit are 0.6 μg/L and 2 μg/L respectively.The intra-day precision and inter-day precision are 1.2%~2.7% and 1.9%~3.8% respectively.The recovery rate is 88.6%~109.7%.The method is simple,rapid,reproducible and suitable.It is used to detect N-nitrosodiethanolamine in general surfactants.