The porosity, acidity and catalytic properties of zeolite Y desilicated in NaOH, tetrabutylammonium hydroxide (TBAOH) and NaOH/TBAOH mixture were investigated. The parent dealuminated zeolite Y of Si/Al = 31 contained very strongly acidic Si-OH-Al groups (more acidic than in other zeolites). These OH groups were also homogeneous. Desilication in NaOH solution extracted ca. 80% of Si but caused the amorphization of zeolite, loss of micropore system and of zeolitic acidity. On the other hand, TBAOH removed a small fraction of the Si, and preserved the crystallinity, porosity and acidity. Nevertheless, the NaOH/TBAOH treatment extracted about half of Si without a loss of crystallinity and zeolite microporosity. The mesopore volume and surface increased distinctly. Both concentration of Brønsted and Lewis acid sites also increased. Remarkably, the acid strength of the Si-OH-Al groups did not change upon desilication in the NaOH/TBAOH. The consequence of the enhanced mesoporosity, sites density, preservation of microporosity and very high acid strength was the catalytic activity in α-pinene isomerization that increased significantly.

研究了在NaOH，四丁基氢氧化铵（TBAOH）和NaOH / TBAOH混合物中脱硅的Y型沸石Y的孔隙率，酸度和催化性能。Si / Al = 31的母体脱铝沸石Y含有非常强酸性的Si-OH-Al基（比其他沸石酸性更高）。这些OH基团也是均质的。在NaOH溶液中脱硅萃取约。Si占80％，但引起沸石的非晶化，微孔系统的丧失和沸石酸度的降低。另一方面，TBAOH除去了一小部分硅，并保留了结晶度，孔隙率和酸度。然而，NaOH / TBAOH处理提取了约一半的Si，而没有结晶性和沸石微孔性的损失。中孔的体积和表面明显增加。布朗斯台德和路易斯酸位的浓度也都增加了。值得注意的是 Si-OH-Al基的酸强度在NaOH / TBAOH中发生脱硅反应后不变。介孔率，位点密度，微孔性的保持和极高的酸强度提高的结果是α-pine烯异构化的催化活性显着提高。