本文主要研究内容
作者刘瑞(2019)在《高硅SSZ-13分子筛的高效合成及甲醇制烯烃催化性能》一文中研究指出:分子筛的合成通常采用水热合成法,大量水溶剂的使用不仅占据反应釜空间,导致合成效率降低,而且母液排放量大、污染严重,因此,开发低污染、高产率的分子筛绿色合成路线已经受到了广泛关注。基于此,近年来还发展了干胶转化法、高浓体系合成法、无溶剂体系合成、气固相合成等多种方法,其中,蒸汽辅助晶化法属于干胶转化法中的一种,因具有母液排放量少、模板剂用量少、反应釜压力低、固体产率高、绿色环保等优点,而受到了广泛的关注,目前,采用蒸汽辅助晶化法已成功制备多种分子筛。SSZ-13分子筛拥有独特的三维孔道结构,能够同时限制较大的分子进出是催化性能的关键,作为甲醇制烯烃反应(MTO)的催化剂目前已实现商业化,但SSZ-13分子筛的水热合成过程通常需要加入大量价格昂贵的有机模板剂,且合成产物晶粒尺寸大、比表面积小、酸量多、抗焦性差、容易失活等缺点限制了它在MTO反应中的应用,因此,寻求模板剂用量少、固体产率高、晶粒大小可控、酸性适宜的SSZ-13分子筛的合成路径具有重要的理论意义和应用价值。基于上述背景,本论文首先考察了高硅SSZ-13分子筛的高浓体系法合成,在此基础上进一步开展了蒸汽辅助晶化法合成高硅SSZ-13分子筛的研究,旨在通过提高硅源利用率和单釜产率提高SSZ-13分子筛的合成效率、降低模板剂用量及减少母液排放。考察了合成过程中的各种影响因素,并测试其MTO催化性能,主要工作如下:1.在低模硅比条件下,采用高浓体系法合成高硅SSZ-13分子筛,旨在减少母液排放,提高硅源利用率及单釜产率。考察不同水硅比、碱硅比、晶化时间对合成产物物化性质和固体产率的影响,通过XRD、SEM、TG-DTG、FT-IR、NH3-TPD表征手段对合成样品的物化性能进行表征,并将高硅铝比SSZ-13分子筛产物用于甲醇制取烯烃反应,进行催化性能测试。结果表明,随着水硅比从20降低至3(H2O/SiO2=203),水热法合成逐渐向高浓体系法转变,固体产率从80%升高到91%,晶粒尺寸大小由2.3μm降至1.6μm,且晶化速率有所加快。此外,在甲醇制取烯烃反应(MTO)中,高浓体系法合成样品的催化寿命随着水硅比的降低而延长,双烯选择性也表现出相同的趋势。2.通过蒸汽辅助晶化法合成高硅SSZ-13分子筛,考察晶化时间、晶化温度、模硅比、碱硅比对合成产物物化性质、固体产率及晶化速率等的影响,并与相同条件下水热法合成样品进行性能对比。结果表明,随着模硅比的降低(SDA/SiO2=0.20.06),蒸汽辅助晶化法合成样品的结晶度由98%轻微降低至91%,且固体产率由95%降低至82%,而水热法合成样品的结晶度从98%显著降低至78%,固体产率从79%降低至67%,此外,在相同模硅比条件下,蒸汽辅助晶化法合成样品的晶粒尺寸较小、比表面积与孔容较大、硅铝比高,在MTO反应中表现出更长的催化寿命。3.进一步对蒸汽辅助晶化法合成过程中凝胶的干燥条件以及反应釜底水量与干胶粉末质量的关系进行深入探讨,并对合成样品进行物化性能表征与MTO催化测试。结果表明,蒸汽辅助晶化法合成过程中凝胶干燥温度和干燥时间对晶化过程有着显著的影响,适当提高凝胶干燥温度和延长干燥时间,能够缩短SSZ-13分子筛的晶化时间;研究发现釜底水量的最低限是满足特定晶化条件下的饱和蒸气压,即与反应釜体积和晶化温度均有关。此外,在达到饱和蒸汽压的前提下,为保证干胶粉末与水蒸汽能充分接触,釜底水量需根据干胶粉末质量进行调整;同时发现,釜底水量在满足饱和蒸气压并可充分接触干胶粉末的条件下,产物晶粒尺寸与形貌不随水量增加而发生明显变化,但总酸量随水量增加而增加,伴随着MTO催化寿命也逐渐缩短。
Abstract
fen zi shai de ge cheng tong chang cai yong shui re ge cheng fa ,da liang shui rong ji de shi yong bu jin zhan ju fan ying fu kong jian ,dao zhi ge cheng xiao lv jiang di ,er ju mu ye pai fang liang da 、wu ran yan chong ,yin ci ,kai fa di wu ran 、gao chan lv de fen zi shai lu se ge cheng lu xian yi jing shou dao le an fan guan zhu 。ji yu ci ,jin nian lai hai fa zhan le gan jiao zhuai hua fa 、gao nong ti ji ge cheng fa 、mo rong ji ti ji ge cheng 、qi gu xiang ge cheng deng duo chong fang fa ,ji zhong ,zheng qi fu zhu jing hua fa shu yu gan jiao zhuai hua fa zhong de yi chong ,yin ju you mu ye pai fang liang shao 、mo ban ji yong liang shao 、fan ying fu ya li di 、gu ti chan lv gao 、lu se huan bao deng you dian ,er shou dao le an fan de guan zhu ,mu qian ,cai yong zheng qi fu zhu jing hua fa yi cheng gong zhi bei duo chong fen zi shai 。SSZ-13fen zi shai yong you du te de san wei kong dao jie gou ,neng gou tong shi xian zhi jiao da de fen zi jin chu shi cui hua xing neng de guan jian ,zuo wei jia chun zhi xi ting fan ying (MTO)de cui hua ji mu qian yi shi xian shang ye hua ,dan SSZ-13fen zi shai de shui re ge cheng guo cheng tong chang xu yao jia ru da liang jia ge ang gui de you ji mo ban ji ,ju ge cheng chan wu jing li che cun da 、bi biao mian ji xiao 、suan liang duo 、kang jiao xing cha 、rong yi shi huo deng que dian xian zhi le ta zai MTOfan ying zhong de ying yong ,yin ci ,xun qiu mo ban ji yong liang shao 、gu ti chan lv gao 、jing li da xiao ke kong 、suan xing kuo yi de SSZ-13fen zi shai de ge cheng lu jing ju you chong yao de li lun yi yi he ying yong jia zhi 。ji yu shang shu bei jing ,ben lun wen shou xian kao cha le gao gui SSZ-13fen zi shai de gao nong ti ji fa ge cheng ,zai ci ji chu shang jin yi bu kai zhan le zheng qi fu zhu jing hua fa ge cheng gao gui SSZ-13fen zi shai de yan jiu ,zhi zai tong guo di gao gui yuan li yong lv he chan fu chan lv di gao SSZ-13fen zi shai de ge cheng xiao lv 、jiang di mo ban ji yong liang ji jian shao mu ye pai fang 。kao cha le ge cheng guo cheng zhong de ge chong ying xiang yin su ,bing ce shi ji MTOcui hua xing neng ,zhu yao gong zuo ru xia :1.zai di mo gui bi tiao jian xia ,cai yong gao nong ti ji fa ge cheng gao gui SSZ-13fen zi shai ,zhi zai jian shao mu ye pai fang ,di gao gui yuan li yong lv ji chan fu chan lv 。kao cha bu tong shui gui bi 、jian gui bi 、jing hua shi jian dui ge cheng chan wu wu hua xing zhi he gu ti chan lv de ying xiang ,tong guo XRD、SEM、TG-DTG、FT-IR、NH3-TPDbiao zheng shou duan dui ge cheng yang pin de wu hua xing neng jin hang biao zheng ,bing jiang gao gui lv bi SSZ-13fen zi shai chan wu yong yu jia chun zhi qu xi ting fan ying ,jin hang cui hua xing neng ce shi 。jie guo biao ming ,sui zhao shui gui bi cong 20jiang di zhi 3(H2O/SiO2=203),shui re fa ge cheng zhu jian xiang gao nong ti ji fa zhuai bian ,gu ti chan lv cong 80%sheng gao dao 91%,jing li che cun da xiao you 2.3μmjiang zhi 1.6μm,ju jing hua su lv you suo jia kuai 。ci wai ,zai jia chun zhi qu xi ting fan ying (MTO)zhong ,gao nong ti ji fa ge cheng yang pin de cui hua shou ming sui zhao shui gui bi de jiang di er yan chang ,shuang xi shua ze xing ye biao xian chu xiang tong de qu shi 。2.tong guo zheng qi fu zhu jing hua fa ge cheng gao gui SSZ-13fen zi shai ,kao cha jing hua shi jian 、jing hua wen du 、mo gui bi 、jian gui bi dui ge cheng chan wu wu hua xing zhi 、gu ti chan lv ji jing hua su lv deng de ying xiang ,bing yu xiang tong tiao jian xia shui re fa ge cheng yang pin jin hang xing neng dui bi 。jie guo biao ming ,sui zhao mo gui bi de jiang di (SDA/SiO2=0.20.06),zheng qi fu zhu jing hua fa ge cheng yang pin de jie jing du you 98%qing wei jiang di zhi 91%,ju gu ti chan lv you 95%jiang di zhi 82%,er shui re fa ge cheng yang pin de jie jing du cong 98%xian zhe jiang di zhi 78%,gu ti chan lv cong 79%jiang di zhi 67%,ci wai ,zai xiang tong mo gui bi tiao jian xia ,zheng qi fu zhu jing hua fa ge cheng yang pin de jing li che cun jiao xiao 、bi biao mian ji yu kong rong jiao da 、gui lv bi gao ,zai MTOfan ying zhong biao xian chu geng chang de cui hua shou ming 。3.jin yi bu dui zheng qi fu zhu jing hua fa ge cheng guo cheng zhong ning jiao de gan zao tiao jian yi ji fan ying fu de shui liang yu gan jiao fen mo zhi liang de guan ji jin hang shen ru tan tao ,bing dui ge cheng yang pin jin hang wu hua xing neng biao zheng yu MTOcui hua ce shi 。jie guo biao ming ,zheng qi fu zhu jing hua fa ge cheng guo cheng zhong ning jiao gan zao wen du he gan zao shi jian dui jing hua guo cheng you zhao xian zhe de ying xiang ,kuo dang di gao ning jiao gan zao wen du he yan chang gan zao shi jian ,neng gou su duan SSZ-13fen zi shai de jing hua shi jian ;yan jiu fa xian fu de shui liang de zui di xian shi man zu te ding jing hua tiao jian xia de bao he zheng qi ya ,ji yu fan ying fu ti ji he jing hua wen du jun you guan 。ci wai ,zai da dao bao he zheng qi ya de qian di xia ,wei bao zheng gan jiao fen mo yu shui zheng qi neng chong fen jie chu ,fu de shui liang xu gen ju gan jiao fen mo zhi liang jin hang diao zheng ;tong shi fa xian ,fu de shui liang zai man zu bao he zheng qi ya bing ke chong fen jie chu gan jiao fen mo de tiao jian xia ,chan wu jing li che cun yu xing mao bu sui shui liang zeng jia er fa sheng ming xian bian hua ,dan zong suan liang sui shui liang zeng jia er zeng jia ,ban sui zhao MTOcui hua shou ming ye zhu jian su duan 。
论文参考文献
论文详细介绍
论文作者分别是来自太原理工大学的刘瑞,发表于刊物太原理工大学2019-07-26论文,是一篇关于分子筛论文,沸石论文,蒸汽辅助晶化论文,高硅铝比论文,甲醇制烯烃论文,太原理工大学2019-07-26论文的文章。本文可供学术参考使用,各位学者可以免费参考阅读下载,文章观点不代表本站观点,资料来自太原理工大学2019-07-26论文网站,若本站收录的文献无意侵犯了您的著作版权,请联系我们删除。
标签:分子筛论文; 沸石论文; 蒸汽辅助晶化论文; 高硅铝比论文; 甲醇制烯烃论文; 太原理工大学2019-07-26论文;