摘要
新型高硅Y(NHSY)沸石的研究 Ⅰ.NHSY沸石的制备刘兴云,裴站芬,佘励勤,李宣文(北京大学化学系,北京100871)关键词NaY沸石,骨架改性,化学脱铝,NHSY沸石,草酸为了提高用于制备裂化催化剂的Y沸石的稳定性,必须对其骨架进行改性.实用的...
A new prosess for the modification of zeolite framework has been developed. The prosess consists of chemical dealumination and hydrothermal treatment of the zeolite, taking the chemical dealumination as the first step. It can be illustrated as follows:NaY zeolite has been treated by this prosess with new reagents (oxalic acid and/or ammonium oxalate). As the number of framework aluminum per unit cell in the zeolite decreases, the unit cell size reduces, the asymmetric and symmetric stretching bands shift to higher wavenumbers and the crystal collapse temperature increases. After each treatment step, the product shows tile characteristic infrared spectrum and special pore size distribution. NHSY zeolite prepared by the new process has good crystallinity and very developed secondary pores.
基金
国家自然科学基金
关键词
骨架改性
化学脱铝
NHSY沸石
NaY zeolite,framework modification,chemical dealumination,high-silica Y zeolite, oxalic acid