【作者】 陈云建；

【导师】 丁福臣；

【作者基本信息】 北京化工大学 ， 化学工艺， 2009， 硕士

【摘要】 采用静态晶化法合成了MCM-22与MCM-41,采用纳米组装法合成了微孔-介孔复合MCM-22/MCM-41分子筛。采用XRD、FT-IR、TG-DTA、NH₃-TPD、吡啶-IR和N₂-吸附脱附等多种表征方法进行物化性质分析表征。在高压微反装置对合成的MCM-22/MCM-41和MCM-22进行了催化裂化汽油降烯烃的研究。微孔-介孔MCM-22/MCM-41复合分子最佳的合成条件如下:原料的老化时间为7h;第一步控制合成MCM-22微孔相的晶化时间为4.5d,第二步合成MCM-41介孔相的晶化时间为1d;第二步合成介孔相时pH值为10.5,模板剂CTAB（十六烷基三甲基溴化铵）的用量和MCM-22前体质量比为0.12,晶化温度为105℃。复合分子筛的表征结果表明:MCM-22/MCM-41的大角度XRD图具有微孔相MCM-22特征峰,小角度XRD图具有MCM-41特征峰;MCM-22/MCM-41的FT-IR图具有介孔和微孔分子筛的骨架振动;MCM-22和MCM-22/MCM-41的原粉TG-DTA图分析得出的CTAB占复合原粉总重的5%;H-MCM-22/MCM-41的总酸量为4.176mmol·g^-1,L酸/B酸的值为0.3537,其总酸量和B酸要大于H-MCM-22;纳米组装法合成的MCM-22/MCM-41的N₂-吸附脱附等温线呈现出介孔分子筛和微孔分子筛的部分特征,说明了复合分子筛成功引入了介孔,在介孔相和微孔相范围都有孔径分布,分别为2.2 nm和0.48 nm,介孔孔壁厚2.2 nm。H-MCM-22/MCM-41复合分子筛用于FCC汽油降烯烃反应研究,发现最优的操作条件是温度400℃、压力2 Mpa、空速3 h^-1;考察了H-MCM-22/MCM-41和H-MCM-22用于FCC汽油降烯烃性能对比,发现H-MCM-22/MCM-41复合分子筛较单组分H-MCM-22具有更强的芳构化性能,并且初始活性高,稳定性好。催化裂化汽油经复合分子筛催化改质,芳烃体积分数由27.8%升至51.1%,烯烃体积分数由35.5%降至5.80%;H-MCM-22/MCM-41催化剂具有较好的再生性能,其失活主要是积炭失活;相比于H-ZSM-5、H-Y、H-MCM-41、H-β、机械混合H-MCM-22/MCM-41和H-MCM-22分子筛的降烯烃改质性能,纳米组装法合成的H-MCM-22/MCM-41复合分子筛的FCC汽油降烯烃改质性能最佳。更多还原

【Abstract】 MCM-22 and A1-MCM-41 were synthesized by the method of static crystallization.Micro/mesoporous MCM-22/MCM-41 composites were prepared by the method of nano-assemblling method and synthesis conditions were optimized.Series of catalysts prepared were characterized by the method of XRD,FT-IR,TG-DTA,NH₃-TPD, PYR-IR,and N₂-Adsorption and desorption.The reaction performance of MCM-22/MCM-41 and MCM-22 catalyst for the various FCC gasoline fractions was investigated on a series fixed bed reactor.In the synthesis process of MCM-22/MCM-41,The optimal synthesis conditions of MCM-22/MCM-41 was as follows:the aging time of raws is 7h;the first step of crystallization time for MCM-22 is 4.5d; the second step of crystallization time for MCM-41 is 1d;Mass ratio of CTAB and MCM-22 Precursors is 0.12;The second step of the crystallization temperature for MCM-41 is 105℃. The micropore characteristic peaks were showed at wide angle XRD patterns and The mesopore characteristic peaks were showed at low-angle XRD patterns;The framework vibration of micropore and mesopore could be found in FT-IR spectra;The proportion of template of CTAB is 5%in total weight of composites;There were more acid contents（4.176 mmol·g-1） and bronsted acids in H-MCM-22/MCM-41;Some characteristic of mesopore and micropore could be found in the N2 adsorption- desorption isotherms of MCM-22/MCM-41.The pore size distribution of micropore,The pore size distribution of mesopore and the hole wall were 2.2 nm,0.48 nm and 2.2 nm.The reaction performance of H-MCM-22/MCM-41 catalyst for the FCC gasoline fractions was investigated.The optimal conditions of H-MCM-22/MCM-41 was as follows,reaction temperature 400℃, reaction pressure 2 MPa,LHSV 3 h^-1;The reaction performances of H-MCM-22 and H-MCM-22/MCM-41 catalysts were compared.The results showed that after 2h reaction,the content of olefin in liquid product was dropped from 35.5%to 5.80%and aromatics are raised from 27.8%to 51.1%.And the activity and stability of H-MCM-22/MCM-41 catalyst for the aromatization were higher than H-MCM-22;The H-MCM-22/MCM-41 catalyst had good regeneration performance,and It was confirmed that the reaction of catalyst deactivation was coke deactivation;Compared with H-ZSM-5,H-Y,H-β,H-MCM-22,H- MCM-41 and H-MCM-22/MCM-41 composite of Mechanical mixture, the reaction performances of H-MCM-22/MCM-41 which was synthesised by nano- assemblling method were the highest in these zeolite composites.更多还原