Aromatic Hydrocarbon Formation in HSAPO-18 Catalysts: Cage Topology and Acid Site Density
Aromatic Hydrocarbon Formation in HSAPO-18 Catalysts: Cage Topology and Acid Site Density
复制标题
DOI：
10.1021/la011556i
复制
发表时间：
2002-07
期刊：
影响因子：
3.9
通讯作者：
D. M. Marcus;Weiguo Song;and Ling L. Ng;J. F. Haw
中科院分区：
文献类型：
--
作者：
D. M. Marcus;Weiguo Song;and Ling L. Ng;J. F. Haw
制备了具有不同酸位点密度的硅铝磷酸盐HSAPO-18的两个样品，表征并与更广泛研究的替代催化剂HSAPO-34相比作为甲醇制烯烃催化剂进行了研究。特别地，我们使用温和的酸消化和GC-MS分析来分析在450 °C下甲醇转化期间作为失活的催化剂的笼中形成的芳烃。HSAPO-18和HSAPO-34之间最显著的差异是在前者失活期间芘的积累，而不是在后者中菲的积累。对每种类型的七个失活催化剂床的重复分析揭示了以下芘/菲比率：HSAPO-18，7.70 ± 4.96; HSAPO-34，0.414 ± 0.040（95%置信度）。我们把这归因于笼状拓扑结构的细微差异。具有最低酸位点密度的HSAPO-18催化剂也积累了可观量的具有1至4个甲基的芘。我们能够合成芘作为主要的...
Two samples of the silico-aluminophosphate HSAPO-18 with different acid site densities were prepared, characterized, and studied as methanol-to-olefin catalysts in comparison with the more widely studied alternate catalyst HSAPO-34. In particular, we used mild acid digestion and GC-MS analysis to profile the aromatic hydrocarbons forming in the cages as the catalysts deactivated during methanol conversion at 450 °C. The most notable difference between HSAPO-18 and HSAPO-34 was the accumulation of pyrene during the deactivation of the former as opposed to phenanthrene in the latter. Repetitive analyses of seven deactivated catalyst beds of each type revealed the following pyrene/phenanthrene ratios: HSAPO-18, 7.70 ± 4.96; HSAPO-34, 0.414 ± 0.040 (95% confidence). We attribute this to subtle differences in cage topology. The HSAPO-18 catalyst with the lowest acid site density also accumulated appreciable amounts of pyrenes with one to four methyl groups. We were able to synthesize pyrene as the predominant...