Hayasaka Kazuaki, Liang Duoduo, Huybrechts Ward, De Waele Bart R, Houthoofd Kristof J, Eloy Pierre, Gaigneaux Eric M, van Tendeloo Gustaaf, Thybaut Joris W, Marin Guy B, Denayer Joeri F M, Baron Gino V, Jacobs Pierre A, Kirschhock Christine E A, Martens Johan A
Centre for Surface Chemistry and Catalysis, Catholic University of Leuven, Kasteelpark Arenberg 23, B-3001 Leuven, Belgium.
Chemistry. 2007;13(36):10070-7. doi: 10.1002/chem.200700967.
An ZSM-22 aluminosilicate zeolite was synthesized using the hydrothermal gel method at 150 degrees C. Products obtained after different synthesis times were characterized using various techniques and catalytic testing. Massive formation of ZSM-22 nanocrystals occurs after only a short synthesis time, appearing as isolated rods with a cross section of 12+/-4 nm. Nanorods have aluminum enriched at their external surface. Later in the crystallization process nanorods align and fuse sideways, whereby the external surface is systematically converted into an internal micropore surface. The formation of aluminum bearing micropores by the joining of nanorod surfaces is responsible for the enhanced catalytic activity. For this, the zeolite synthesis of nanoscale crystallites is ineffective for enhancing catalytic activity.
采用水热凝胶法在150℃合成了ZSM - 22铝硅酸盐沸石。对不同合成时间后获得的产物进行了各种技术表征和催化测试。仅经过较短的合成时间就会大量形成ZSM - 22纳米晶体，呈现为横截面为12±4nm的孤立棒状。纳米棒的外表面富含铝。在结晶过程后期，纳米棒会排列并侧向融合，从而使外表面系统地转化为内部微孔表面。纳米棒表面结合形成含铝微孔是催化活性增强的原因。为此，纳米级微晶的沸石合成对于增强催化活性是无效的。
