The ZnO catalysts supported on Silicalite‐1 zeolites with different crystallite sizes (0.08, 0.35, 1 and 1.7 μm, respectively) and 5% Zn were synthesized via an incipient wetness method. The catalysts were characterized by XRD, N₂ adsorption, SEM, TEM‐EDX, DRIFT spectra and NH₃‐TPD, and their catalytic performance in isobutane dehydrogenation assisted by CO₂ was investigated. The catalytic activity is strongly dependent on the crystallite size of Silicalite‐1 support. The ZnO/S‐1‐0.35 catalyst with ca . 0.35 μm crystallite size displays the highest activity, affording an initial isobutane conversion of 51.0% and 74.5% isobutene selectivity. This can be attributed to a higher amount of acid sites present on this catalyst as well as the largest amount of nest silanols possessed by the S‐1‐0.35 support.

中文翻译：

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Silicalite-1负载的ZnO催化剂上CO2辅助的异丁烷脱氢：载体微晶尺寸的影响

通过初期润湿法合成了负载在具有不同微晶尺寸（分别为0.08、0.35、1和1.7μm）的Silicalite-1沸石上的ZnO催化剂和5％的Zn。通过XRD，N ₂吸附，SEM，TEM-EDX，DRIFT光谱和NH ₃ -TPD对催化剂进行了表征，并研究了它们在CO ₂辅助下对异丁烷脱氢的催化性能。催化活性在很大程度上取决于Silicalite-1载体的微晶尺寸。在ZnO / S-1-0.35催化剂与CA。0.35μm的微晶尺寸显示出最高的活性，初始异丁烷转化率为51.0％，异丁烯选择性为74.5％。这可以归因于该催化剂上存在的酸性位点数量更高，以及S-1-0.35载体拥有的最大嵌套硅醇含量。