木质纤维素生物质催化转化制备苯甲酸

In the present work, we reported a novel route for the conversion of lignocellulosic biomass (sawdust) to a high-value chemical of benzoic acid under atmospheric pressure. The trans- formation involved the catalytic pyrolysis of sawdust into aromatics, the decomposition of heavier alkylaromatics to toluene, and the liquid-phase oxidation of toluene-rich aromatics to benzoic acid. The production of the desired benzoic acid from the sawdust-derived aro- matics, with the benzoic acid selectivity of 85.1 C-mol% and nearly complete conversion of toluene, was achieved using the MnO₂/NHPI catalyst at 100 ℃ for 5 h. The in uence of adding methanol on the catalytic conversion of sawdust to the core intermediate of toluene was also investigated in detail.     

Renewable \begin{document}$p$\end{document}-Xylene Production by Co-catalytic Pyrolysis of Cellulose and Methanol

This work developed a one-step process for renewable p-xylene production by co-catalytic fast pyrolysis (co-CFP) of cellulose and methanol over the different metal oxides modified ZSM5 catalysts. It has been proven that \begin{document}${\rm{L}}{{\rm{a}}_{\rm{2}}}{{\rm{O}}_{\rm{3}}}$\end{document}-modified ZSM5(80) catalyst was an effective one for the production of bio-based p-xylene. The selectivity and yield of p-xylene strongly depended on the acidity of the catalysts, reaction temperature, and methanol content. The highest p-xylene yield of 14.5 C-mol% with a p-xylene/xylenes ratio of 86.8% was obtained by the co-CFP of cellulose with 33wt% methanol over 20%\begin{document}${\rm{L}}{{\rm{a}}_{\rm{2}}}{{\rm{O}}_{\rm{3}}}$\end{document}-ZSM5(80) catalyst. The deactivation of the catalysts during the catalytic pyrolysis process was investigated in detail. The reaction pathway for the formation of p-xylene from cellulose was proposed based on the analysis of products and the characterization of catalysts.     

多聚磷酸铵对再造烟叶热解行为与CO释放量的影响

应用热重分析研究多聚磷酸铵（APP）对再造烟叶热解行为的影响．热分析结果表明,APP降低再造烟叶热降解速率及其热释放量、促进了碳的形成,对再造烟叶的热降解起一定的阻碍作用．此外APP显著影响再造烟叶的热解过程中的气相产物,再造烟叶的CO单支释放量与单口释放量随着APP含量的增加快速下降．慢速热解与闪解实验结果显示升温速率是APP降低C0释放的关键因素。     

Interactions of tobacco shred and other tobacco-based materials during co-pyrolysis and co-combustion

Journal of Thermal Analysis and Calorimetry - The interactions of tobacco shred with other tobacco-based materials, like expanded cut tobacco, cut reconstituted tobacco and expanded cut stem during...     

Influence of chemical composition on martensitic transformation of MnNiIn shape memory alloys

The most extensively studied Heusler alloys are those based on the Ni–Mn–Ga system. However, to overcome the high cost of Gallium and the generally low martensitic transformation temperature, the search for Ga-free alloys has been recently attempted, particularly, by introducing In, Sn or Sb. In this work, two shape memory alloys, Mn₅₀Ni_50?xIn_x (x = 7.5 and 10), were obtained by rapid solidification. We outline their structural and thermal behaviour. The structural austenite–martensite transformation was checked by calorimetry. The transformation temperatures decrease as In content increases. The same pattern is reflected in entropy and enthalpy changes linked to transformation. The control of the valence electron by atom (e/a) determines the transformation temperatures range in this kind of alloys, and it is possible to develop alloys that can be candidates in applications such as sensors and actuators. In addition, X-ray diffraction was performed to verify the crystalline structure at room temperature.

     

Extraction of Lignin from Tobacco Stem using Ionic Liquid

Lignin only accounts for about 6% of total mass in tobacco stem, but it influences the harmful substances in the side stream smoke of cigarette in a significant way. Traditional researches focus only on the determination of lignin content. In the present work, we investigate four typical imidazolium-based ionic liquids for efficient extraction of lignin under mild conditions and 1-ethyl-3-methylimidazolium diethylphosphate ([Emim][DEP]) shows the best results. The pretreatment of stem using water at 80 ℃ for 30 min can not only remove most of the sugars but also loose the microfibers. The extractive rate of lignin reaches 85.38% at 150 ℃ for 4 h and the purity of lignin is 90.21%.