Pyrolytic characteristics of acid hydrolysis residue from corncob

 Pyrolytic characteristics of acid hydrolysis residue from corncob (residue in short), were studied using thermal analyzer, tube furnace, gas chromatogram (GC), gas chromatogram-mass spectrometry (GC-MS) and scanning electronic microscopy (SEM). The thermogravimetric analysis shows that pyrolysis of the residue mainly occurs in 280℃~450℃ with only one obvious mass loss peak. The tube furnace test indicates that with increase of temperature gas yield increases greatly, while char and tar yield show decreasing trend. Among the gaseous products, with increase in temperature, H₂ and CH₄ increase, CO₂ decreases; compared with corncob, the residue releases more CO, H₂ and CH₄, and less CO₂ during pyrolysis. The main compounds identified through GC-MS are phenol and polycyclic aromatic hydrocarbons. SEM images show that char prepared at higher temperature is more uniformly crystallized.