Determination of aromatic amines in water sample with hollow fiber protected liquid phase microextraction coupled microwave assisted derivazation and preconcentration by GC-ECD

• Main Authors: Yu-Chang Shih, 施育昌
• Other Authors: 鄭政峯
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/u8fm8u

碩士 === 國立中興大學 === 化學系所 === 99 === In the present study, an analytic method for the determination of aromatic amines (aniline, o-anisidine, 4-chloroaniline) has been investigated. This new method combines the hollow fiber protected liquid phase microextraction (HF-LPME) with on-line microwave assisted derivatization and concentration. In this work, HF-LPME is assembled as a microdialysis sampling tool to concentrate and exclude the analytes in water samples. After the extraction, the extraction solvent was mixed with derivatization agent (trifluoroacetic anhydride) and flow into microwave oven through the on-line hollow fiber membrane. Microwave energy is utilized to accelerate derivatization reaction and also to heat the silicon carbide which is present inside the microwave oven. Under the optimal microwave power, the extraction solvent is vaporized from the silicon carbide and reached to concentration valve and then it was taken to injection for GC-ECD analysis. Parameters affecting the extraction efficiency are well optimized and the best extraction was achieved by using ethyl acetate as extraction solvent, inject rate of 0.12 mL/min, sample temperature of 35 oC, stirring rate of 150 rpm, addition of 0.125 % sodium chloride, microwave power at 158 Watts and extraction time for 25 mins. Under the selected conditions, good linearity was obtained in the range of aniline and o-anisidine was 1-50 μg/L, and for 4-chloroaniline was 0.002-0.1 μg/L. The correlation coefficients were between 0.9951-0.9984. Enrichment factors were ranged 169-545. The limit of detection were 0.2 μg/L for aniline, 0.4 μg/L for o-anisidine, and 0.001 μg/L for 4-chloroaniline. In real sample analysis, aniline was detected at 1.66 mg/L and 4-chloroaniline 0.006mg/L in industrial waste water. The recovery of three aromatic amines was between 80-99% and RSD was between 3.5-10.3%. Aniline was detected at 3.13 mg/kg in dress materials. The recovery of three aromatic amines was between 80-98% and RSD was between 4.6-8.1%. The proposed method provides a simple, sensitive, flexible, and eco-friendly procedure to enrich and determine aromatic amines in aqueous samples.