不同拓扑结构分子筛催化2-甲基萘酰化反应性能对比研究  

Comparative study on the catalytic performance of zeolite catalysts with different topologies in 2-methylnaphthalene acylation reaction

作　　者：李军芳 LI Junfang(China Coal Research Institute Corporation Ltd.,Beijing 100013,China;National Energy Technology&Equipment Laboratory of Coal Utilization and Emission Control,Beijing 100013,China;Beijing Key Laboratory of Coal Based Carbon Materials,Beijing 100013,China;CCTEG Low-carbon Technology Institute,Beijing 100013,China)

机构地区：[1]煤炭科学技术研究院有限公司,北京100013 [2]国家能源煤炭高效利用与节能减排技术装备重点实验室,北京100013 [3]煤基节能环保炭材料北京市重点实验室,北京100013 [4]中国煤科低碳技术研究院,北京100013

出　　处：《煤质技术》2024年第6期79-86,共8页Coal Quality Technology

基　　金：中国煤炭科工集团有限公司科技创新创业资金专项项目(2023-2-TD-ZD008)。

摘　　要：2,6-萘二甲酸是合成特种聚酯聚萘二甲酸乙二醇酯(PEN)的重要单体,利用2-甲基萘通过酰化、氧化、纯化工艺可得到2,6-萘二甲酸,工艺中的酰化反应至关重要。目前2-甲基萘酰化反应中的催化剂通常采用Lewis酸AlCl 3且催化体系的反应转化率高、选择性好,但反应淬灭过程会产生大量的酸性含铝废水,反应体系对设备的材质要求高。基于分子筛具有择型性高、热稳性好、易与产物分离等优势且在多种酰基化反应中表现出良好的催化活性,以2-甲基萘和丁酸酐为原料经分子筛固体酸催化的酰基化反应制备2-甲基-6-丁酰基萘,采用XRD、BET、SEM、NH 3-TPD等方法对催化剂结构物性进行表征,对比研究BEA、MFI、MWW骨架拓扑结构的H-Beta、H-HZSM-5、H-MCM-22分子筛催化性能,探讨反应机理并考察分子筛催化剂的回用性能。研究表明,与具有十元环特征孔道的H-ZSM-5分子筛相比,具有十二元环特征孔道的H-Beta分子筛表现出更好的催化活性,BEA骨架拓扑的分子筛具有较高的选择性;在H-Beta分子筛催化下,反应条件为2-甲基萘与丁酸酐摩尔比1∶1、2-甲基萘0.05 mol、催化剂2 g、190℃反应10 h,丁酸酐转化率为57.42%,其中2,6-位选择性为44.98%,2,7-位选择性为28.62%;H-MCM-22分子筛催化体系下,丁酸酐的转化率为31.66%,但生成产物不以期望的目标物为主;H-MCM-5分子筛由于孔道尺寸小,不适用于该体系,在液相体系中丁酸酐转化率<3%且未生成目标物。分子筛具有优良的回用性能,使用后的H-Beta分子筛通过高温焙烧再生后,催化剂的性能得到恢复,体现沸石分子筛催化剂的可回收和可重复利用的优点,该研究可为以中国丰富的含萘资源为原料制备高端聚酯单体提供颇具潜力的分子筛催化体系。2,6-Naphthalenedicarboxylic acid is an important monomer for the synthesis of special polyester polyethylene naphthalate(PEN).2,6-Naphthalenedicarboxylic acid can be obtained by acylation,oxidation and purification of 2-methylnaphthalene.The acylation reaction is very important in this process.At present,Lewis acid AlCl 3 is usually used as the catalyst in the 2-methylnaphthalene acylation reaction.The catalytic system has high conversion rate and good selectivity,but the reaction quenching process will produce a large amount of acidic aluminum-containing wastewater,and the reaction system has high requirements for the material of the equipment.Based on the advantages of molecular sieves such as high selectivity,good thermal stability,easy separation from products and good catalytic activity in various acylation reactions,2-methyl-6-butyrylnaphthalene was prepared by acylation reaction of 2-methyl-naphthalene and butyric anhydride catalyzed by molecular sieve solid acid.The structure and properties of the catalysts were characterized by XRD,BET,SEM and NH 3-TPD.The catalytic properties of H-Beta,H-ZSM-5 and H-MCM-22 molecular sieves with BEA,MFI and MWW skeleton topologies were compared.The reaction mechanism was discussed and the reuse performance of molecular sieve catalyst was investigated.The results showed that compared with H-ZSM-5 zeolite with ten-membered ring characteristic channel,H-Beta zeolite with twelve-membered ring characteristic channel showed better catalytic activity,and the zeolite with BEA skeleton topology had higher selectivity.Under the catalysis of H-Beta molecular sieve,the reaction conditions were as follows:the molar ratio of 2-methylnaphthalene to butyric anhydride was 1∶1;2-methylnaphthalene was 0.05 mol,catalyst was 2 g,reaction temperature was 190℃,reaction time was 10 h,the conversion of butyric anhydride was 57.42%,the selectivity of 2,6-position was 44.98%,the selectivity of 2,7-position was 28.62%.The conversion rate of butyric anhydride was 31.66%under the catalytic system

关 键 词：酰化反应 2-甲基萘 分子筛催化剂 拓扑结构 回用性能 特征孔道 反应机理 

分 类 号：TQ203.2[化学工程—有机化工]