登录    注册    忘记密码

详细信息

微波辅助杨木快速苯酚液化及产物表征     被引量:5

Rapid Wood Liquefaction with Phenol by Microwave Heating and Product Characterization

文献类型:期刊文献

中文题名:微波辅助杨木快速苯酚液化及产物表征

英文题名:Rapid Wood Liquefaction with Phenol by Microwave Heating and Product Characterization

作者:李改云[1] 朱显超[1] 邹献武[1] 向琴[1] 何玉婵[1]

第一作者:李改云

机构:[1]中国林业科学研究院木材工业研究所

年份:2014

卷号:50

期号:11

起止页码:115-121

中文期刊名:林业科学

外文期刊名:Scientia Silvae Sinicae

收录:CSTPCD;;Scopus;北大核心:【北大核心2011】;CSCD:【CSCD2013_2014】;

基金:国家林业局"948"项目(2012-4-28)

语种:中文

中文关键词:微波加热;杨木;苯酚液化;产物表征

外文关键词:microwave heating;poplar;phenolation;product characterization

分类号:TQ351

摘要:针对传统木材苯酚液化技术中存在的反应时间长、产物黏度高和反应活性降低等问题,采用微波加热方式,将杨木木粉在酸化苯酚溶剂中进行快速解聚反应。结果表明,微波加热条件下杨木苯酚液化的适宜条件为:木粉含水率30%~40%,液化时间15 min,苯酚与木粉的比例(P/W)2.5,木粉粒径0.18~0.25 mm,在此条件下木材液化率达到87%。微波加热的木材苯酚液化速率比传统油浴加热提高至少6倍。木材被降解为醇类、酸类、醚类、醛类和酚类等低分子质量物质,液化产物黏度显著降低,仅为3015 mPa·s,且与甲醛的反应活性较高,100 g液化产物反应消耗的甲醛达2.1 mol。微波加热与传统加热下的木材苯酚液化反应历程不尽相同,主要表现在纤维素和半纤维素降解为单糖后,单糖可进一步断裂为2,3-丁二醇、1,2-丙二醇、乙二醇和乙二醛等物质,这些物质相互之间可以发生脱水、羟醛缩合等反应进一步生成 2-乙氧基-丙烷,1,1-二乙氧基-乙烷、二异丙基缩甲醛和12-冠醚-4。
A method for fast poplar wood liquefaction in phenol by using microwave energy was successfully developed. The optimum conditions for microwave-assisted poplar wood liquefaction in phenol are as follows: moisture content 30% -40%,reaction time 15 min,phenol to wood (P/W) ratio 2. 5,wood powder diameter 0. 18 -0. 25 mm,and liquefaction yield 87%. It was proved that microwave improved the liquefaction rate at least 6 times faster than conventional heating. Wood was degraded to low molecular weight substances including alcohols, acids, ether, aldehyde and phenolic compounds. Viscosity of liquefied wood products was remarkably decreased from 8 250 mPa·s to 3 015 mPa·s. And 100 g of liquefied wood reacted with about 2. 1 mol of formaldehyde. There were only seven main conpounds,including phenol,2,3-butanediol,1,2-propanediol,2-ethoxy-propane,1,1-diethoxy-ethane,diisopropyl formal and 12-crown-4 in diethyl ether-soluble portions from liquefied wood products. It was concluded that the reaction mechanism was somewhat different between microwave-assisted and traditional wood phenolation. Cellulose and hemicellulose were firstly degraded into monosaccharides. And monosaccharides could be further cracked into 2,3-butanediol,1,2-propanediol,ethylene glycol and ethanedial,and so on. These substances reacted with each other and converted to 2-ethoxy-propane,1,1-diethoxy-ethane,diisopropyl formal and 12-crown-4.

参考文献:

正在载入数据...

版权所有©中国林业科学研究院 重庆维普资讯有限公司 渝B2-20050021-8 
渝公网安备 50019002500408号 违法和不良信息举报中心