PYROLYSIS CHARACTERISTICS OF CORN STALK HEMICELLULOSE IN A TUBULAR REACTOR

The pyrolysis characteristics of corn stalk hemicellulose were investigated in a tubular reactor at different temperatures, with the focus mainly on the releasing profile and forming behaviors of pyrolysis products (gas, char, and tar). The products obtained were further identified using various approaches (including GC, SEM, and GC-MS) to understand the influence of temperature on product properties and compositions. It was found that the devolatilization of hemicellulose mainly occurred at low temperatures (< 500 degrees C), and produced large amounts of tar. A higher reactor temperature was conducive to the yield of gas products, accompanied by a reduction of tar because of the secondary cracking of volatiles. The CO(2) evolved out easily and reached a relatively large yield of 129.2ml/g at 550 degrees C, while CO and H(2) mainly released at higher temperature (700 similar to 900 degrees C). The tar was mainly composed of a range of oxygenated compounds, including ketones, furans, carboxylic acids, and alcohols, and their contents were influenced by the final temperature. An in-depth analysis of the properties of the product generated at different temperatures is favorable for a better understanding of the mechanism of hemicellulose pyrolysis.