Determination of aniline in water by microwave-assisted headspace solid-phase microextraction and gas chromatography

Determination of aniline in wastewater was investigated by microwave-assisted headspace solid-phase microextraction (MA-HS-SPME), for one-step in-situ sample preparation, and gas chromatography. Aniline in the water was evaporated into the headspace under the action of microwave irradiation and adsorbed directly by the SPME fiber. After desorption in the GC injection port and gas chromatography aniline was detected by FID. Conditions affecting the extraction efficiency, for example the pH of the water, addition of salt, microwave power and irradiation time, and desorption conditions were investigated. Experimental results indicated that adjustment of the pH of the water sample to 12 and headspace SPME sampling with a PDMS-DVB fiber under medium-high power irradiation (345 W) for 3 min resulted in the best extraction efficiency. Desorption of aniline was optimum when the SPME fiber was heated at 230°C for 3 min. The detection limit was approximately 0.01 μg mL -1. The proposed method is a simple, fast, and organic-solvent-free procedure for analysis of aniline in water. Application was illustrated by analysis of aniline in wastewater from a polymer factory.