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Cumene is an important intermediate and chemical in chemical industry.In this work,directional preparation of cumene using lignin was achieved by a three-step cascade process.The mixture aromatics were first produced by the catalytic pyrolysis of lignin at 450℃ over 1% Zn/HZSM-5 catalyst,monocyclic aromatics with the selectivity of 85.7 wt% were obtained.Then,the catalytic dealkylation of heavier aromatics resulted in benzene-rich aromatics with 93.6 wt% benzene at 600℃ over Hβ catalyst.Finally,the cumene synthesis was performed by the aromatic alkylation,giving cumene selectivity of 91.6 C-mol% using the[bmim]Cl-2AlCl13 ionic liquid at room temperature for 15 min.Besides,adding a small amount of methanol to the feed can efficiently suppress the coke yield and enhance the aromatics yield.The proposed transformation potentially provides a useful route for production of cumene using renewable lignin. 相似文献
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本文对纤维素和甲醇在不同金属氧化物改性的ZSM5催化剂作用下共催化快速热解实现一步制备可再生对二甲苯的过程进行了研究. 结果表明,镧改性的ZSM5催化剂是生产生物基对二甲苯的有效催化剂. 对二甲苯的选择性和产率主要由催化剂酸性、反应温度和甲醇含量决定. 在20%La2O3-ZSM5(80)催化剂作用下,纤维素与33wt%甲醇共催化快速热解获得对二甲苯的最高收率和对二甲苯/二甲苯的最高比率分别为14.5 C-mol%和86.8%. 本文详细研究了催化热解过程中催化剂的失活,基于产物的分析和催化剂的表征提出了由纤维素制备对二甲苯的可能反应途径. 相似文献
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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. 相似文献
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将Lichrospher diol-5亲水柱和Cortecs C18+反相柱组合,构建了亲水/反相二维液相色谱系统(HILIC/RPLC),理论峰容量为1 117。采用表面积覆盖法定量计算该系统分离多酚类化合物的正交性指数SCG为0.56,表明二维柱系统有着良好的峰分辨率和正交性。利用该系统对滁菊样品甲醇提取液中的多酚进行分离和鉴定,在二维空间中分离得到23个物质的色谱峰,通过对比标准样品和滁菊样品的保留时间和紫外吸收光谱,鉴定出13种多酚类物质,包括芹菜素、香叶木素、金合欢素、金合欢素-7-O-葡糖苷、绿原酸、异鼠李素-3-O-葡糖苷、香叶木素-7-O-葡糖苷、金合欢素-7-O-芸香苷、圣草酚-7-O-葡糖苷、槲皮素苷、异绿原酸A、异绿原酸B、芹菜苷。首次发现滁菊中含有异鼠李素-3-O-葡糖苷、金合欢素-7-O-芸香苷、圣草酚-7-O-葡糖苷、芹菜苷等多酚类化合物。其中,异鼠李素-3-O-葡糖苷首次发现存在于菊属植物中。 相似文献
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对二甲苯是石化行业中一种重要的大宗化学品,而且生物质基对二甲苯的制备在学术和工业领域都具有重要意义.对木质素和甲醇在不同金属氧化物改性的HZSM-5催化剂作用下共催化热解一步法制备可再生的对二甲苯的过程进行了研究.研究结果表明,在HZSM-5催化剂中引入La,Mg,Ce和Zn元素可以调节催化剂的酸强度和强酸性位点,进而促进轻芳烃(如苯和甲苯)烷基化形成对二甲苯以及间/邻二甲苯向对二甲苯的异构化.木质素和甲醇的共催化热解显著地提高了对二甲苯的产率.在20%La_2O_3/HZSM-5催化剂作用下,木质素与33 wt%甲醇共催化热解获得的对二甲苯的最高收率为13.9%,对二甲苯/二甲苯比率为82.7%.并且基于产物的分析以及催化剂的表征,提出了由木质素制备对二甲苯的可能反应途径. 相似文献
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