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"On-line" pyrolysis coupled with gas chromatography (GC) was performed for  quantitative determination of poly(vinylpyrrolidone) (PVP) in wastewater  sample. Gas chromatography-mass spectrometry (GC-MS) showed that the main  product of pyrolysis of PVP, at high temperatures, is N-vinylpyrrolidone  (NVP). After that, different amounts of commercial PVP were pyrolyzed in  order to establish correlation between the amount of generated NVP (its GC  peak area) and the initial mass of pyrolyzed PVP. GC-FID analysis was used  for construction of calibration curve and for quantitative determination of  PVP. Very good linear correlation was obtained between the area of NVP peak,  generated during pyrolysis, and the initial mass of PVP (r2 = 0.998).  Further, solutions of known concentration of PVP were prepared in destilled  water ("spiked samples"). Spiked samples were preextracted with diethyl  ether and n-hexane, and after that, the water-layer was evaporated and  dissolved again in methanol. Analysis of pyrolysates of preextracted spiked  samples showed that the "recovery" of PVP was above 96 mas%. This finding  suggested that pre-extraction could be applied to reduce the concentration  of organic substances that could also be pyrolyzed, and thus hinder  identification and quantitative determination of PVP, without significant  loss of polymer. The sample of an industrial wastewater from Pančevo, Serbia  was investigated in the last part of this work. The sample was preextracted  in the same way as the spiked samples and than pyrolyzed. NVP was identified  by GC-MS in obtained pyrolysate, which was the evidence that PVP was present  in the wastewater sample. NVP was quantified on the basis of the peak area  in GC-FID chromatogram, and than the concentration of PVP in wastewater  sample was calculated based on calibration curve. Concentration of PVP in  industrial wastewater amounted 2.5 mg/L

Quantitative determination of poly(vinylpyrrolidone) by "on-line" pyrolysis coupled to gas chromatography