Influence of temperature and alumina catalyst on pyrolysis of corncob

Abstract

Corncob has been investigated as an alternative feedstock to obtain fuels and chemicals via pyrolysis infixed-bed reactor. The influence of pyrolysis temperature in the range 300–800°C as well as the catalysteffects on the products was investigated in detail and the obtained results were compared. The resultsindicated that a maximum oil yield of 22.2% was obtained at a moderate temperature of 600°C. Theoil yield was reduced when the temperature was increased from 600 to 800°C, whereas the gas yieldincreased.Pyrolysis oils were examined by using instrumental analysis,1H NMR spectroscopy and GC/MS. Thisanalysis revealed that the pyrolysis oils were chemically very heterogeneous at all temperatures. Itwas determined that the most abundant compounds composing the bio-oil were phenolics.It was observed that the catalyst decreased the reaction temperature. Most of the components obtainedusing a catalyst at moderate temperatures was close to those obtained at high temperatures withoutusing a catalyst. Moreover, the use of a catalyst and the high temperatures of the reactions also decreasedthe amount of oxygenated compounds produced.According to these results, corncob bio-oils can be used as fuel and constitute a valuable source ofchemical raw materials.