亚临界水中杉木碱木质素的解聚特性分析

doi:10.3969/j.issn.0253-2417.2015.03.011

摘要/Abstract

摘要： 利用间歇式高压反应釜在250~350 ℃的亚临界水中进行杉木碱木质素的水热解聚反应。通过GC/MS的定性、定量分析以及元素分析和FT-IR,分析反应液相和固相产物的组成与结构变化,探究了不同温度下碱木质素水热解聚的反应特性。结果表明,碱木质素水热解聚反应残渣率在325 ℃时最低,为18.66%。碱木质素在亚临界水中解聚所得的液相产物中酚类化合物GC含量均在80%以上,且随反应温度的升高,酚类化合物种类增加,总酚含量提高。酚类产物中愈创木酚的含量最高,其质量分数在325 ℃时达最高17.71 mg/g。随着反应温度升高,在一定程度上木质素脱氢脱氧,含碳量增加。在325℃时碳基转化率和能量转化率均最高,分别为79.18%和79.95%。在温度低于325 ℃时,水热焦的化学结构与木质素相似,达到350 ℃时,木质素严重缩合炭化。

关键词: 亚临界水, 木质素, 解聚, 酚类化合物, 水热焦

Abstract: Hydrothermal depolymerization of Cunninghamialanceolata alkali lignin were conducted in a batch autoclave at temperatures of 250-350 ℃.The components and characteristics of hydrothermal degraded liquid products and hydrochar were investigated by gas chromatography with mass spectrometry (GC/MS),elemental analyzer and Fourier transforms infrared spectroscopy (FT-IR).The results showed that the least residue (18.66%) was collected at 325 ℃.In addition,the relative content of phenols in liquid products was above 80%,and the types and contents of phenols were both increased with the rise of temperature.Guaiacol was the dominant phenol component,represented 17.71 mg/g at 325 ℃.With the increase of reaction temperature, reductions of hydrogen and oxygen contents were observed,while the carbon content increased.The optimum carbon and energy conversion rates at 325 ℃were 79.18% and 79.95%,respectively.The chemical structures of hydrochars were similar to alkali lignin at temperatures below 325 ℃.However,a serious carbonization of lignin was observed when the temperature was over 350 ℃.

Key words: subcritical water, lignin, depolymerization, phenols, hydrochar

中图分类号:

李霄虹, 武书彬. 亚临界水中杉木碱木质素的解聚特性分析[J]. 林产化学与工业, 2015, 35(3): 60-66.

LI Xiao-hong, WU Shu-bin. Depolymerization Characteristics of Cunninghamialanceolata Alkali Lignin in Subcritical Water[J]. Chemistry and Industry of Forest Products, 2015, 35(3): 60-66.

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