Production of Bio-oil from Rice Stalk Supercritical Ethanol Liquefaction Combined with the Torrefaction Process

详细信息    查看全文

• 作者：Rundong Li ; Bingshuo Li ; Tianhua Yang ; Yinghui Xie ; Xingping Kai
• 刊名：Energy & Fuels
• 出版年：2014
• 出版时间：March 20, 2014
• 年：2014
• 卷：28
• 期：3
• 页码：1948-1955
• 全文大小：444K
• 年卷期：v.28,no.3(March 20, 2014)
• ISSN：1520-5029

文摘

The rice stalk (RS) was pretreated using torrefaction in a fixed-bed reactor at 200, 240, and 280 掳C, respectively. The torrefied rice stalk (TRS) was liquefied in a batch autoclave with supercritical ethanol as the medium at 325 掳C and 14鈥?5 MPa for a residence time of 60 min to obtain bio-oil. The TRS was analyzed via Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). It was observed from SEM results that the compact, uniform, and lamellar structure of RS was broken down, whereas the FTIR and chemical composition analysis results showed that the thermal decomposition of hemicellulose was the main reaction that occurred between 200 and 280 掳C. Gas chromatography鈥搈ass spectrometry (GC鈥揗S) results showed that the bio-oil obtained from TRS at a temperature of 200 掳C had the highest ester content of 30.60% and the lowest acid content of 0.35% and also the alcohols of bio-oil reached the maximum value of 20.56% at a temperature of 240 掳C. The water content slightly decreased from 2.23 to 1.31% when the torrefaction temperature was increased from 200 to 280 掳C, and the heating value reached a maximum value of 32.53 MJ/kg at a temperature of 200 掳C; however, the bio-oil yield gradually decreased from 55.03% of non-torrefied RS to 49.80% of TRS at 200 掳C to 38.56% of TRS at 280 掳C.