کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
9748180 | 1492990 | 2005 | 6 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Influence of parameters on pyrolysis-GC/MS of lignin in the presence of tetramethylammonium hydroxide
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی آنالیزی یا شیمی تجزیه
پیش نمایش صفحه اول مقاله
![عکس صفحه اول مقاله: Influence of parameters on pyrolysis-GC/MS of lignin in the presence of tetramethylammonium hydroxide Influence of parameters on pyrolysis-GC/MS of lignin in the presence of tetramethylammonium hydroxide](/preview/png/9748180.png)
چکیده انگلیسی
Thermally assisted hydrolysis and methylation (THM) with tetramethylammonium hydroxide (TMAH) was performed on spruce milled wood lignin (MWL) in order to investigate THM parameters. The objective was the maximization of information on lignin structure. The main emphasis was laid on the formation of lignin monomer derivatives with intact propane side chain, as these fragments are thought to be indicators of favourable THM conditions. In the tested temperature range (310-710 °C) the lowest temperature of 310 °C was found to produce the highest yield of these monomers. The elution of unmethylated lignin monomers, such as phenols and methoxyphenols, was also minimized at 310 °C. In addition, a number of different TMAH to sample ratios were applied. The yield of the most lignin monomer derivatives was increased by using the highest tested TMAH concentration, whereas some unmethylated products, such as phenol, were unaffected. Methanol as solvent for TMAH was compared to an aqueous solution of TMAH of same concentration in respect of the influence on degradation product yields. The elution of 3,4-dimethoxybenzoic acid methyl ester increased and the yield of 3,4-dimethoxybenzaldehyde decreased when methanol was used. At last a prolonged incubation time of the TMAH-sample mixture was shown to be useful to enhance especially the yield of lignin monomer derivatives with intact propane side chain in case of application of a low TMAH to sample ratio.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Analytical and Applied Pyrolysis - Volume 74, Issues 1â2, August 2005, Pages 104-109
Journal: Journal of Analytical and Applied Pyrolysis - Volume 74, Issues 1â2, August 2005, Pages 104-109
نویسندگان
Andreas Klingberg, Jürgen Odermatt, Dietrich Meier,