Tuning of acidity in CeY catalytic cracking catalysts by controlling the migration of Ce in the ion exchange step through valence changes
Tuning of acidity in CeY catalytic cracking catalysts by controlling the migration of Ce in the ion exchange step through valence changes
复制标题
通过价态变化控制离子交换步骤中 Ce 的迁移来调节 CeY 催化裂化催化剂的酸度
DOI：
10.1016/j.jcat.2015.06.012
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发表时间：
2015-09
影响因子：
7.3
通讯作者：
Shen, Baojian
中科院分区：
文献类型：
--
作者：
Liu, Honghai;Pang, Xinmei;Gao, Xionghou;Shen, Baojian
为了阐明铈-NaY（Ce-NaY）离子交换过程中铈阳离子的迁移过程和由此产生的化学多样性，采用三种煅烧气氛（N2气氛、O2氧化、N2气氛后O2氧化）来研究可变价态（III至IV）对离子迁移、热稳定性和催化活性的影响。结果表明，在氮气保护下，大量Ce-（III）离子进入方钠石笼中，提高了Ce-NaY的热稳定性。在O2-氧化下，大部分Ce-（III）转化为Ce-（IV）并保留在超笼内。Ce-（IV）促进了水的极化，并在红外光谱中在3582 cm− 1处显示出独特的羟基。Ce离子交换的超稳Y沸石（CeUSYO 2）由于Ce离子的位置而表现出最高量的布朗斯台德酸。与CeUSYN 2相比，CeUSYO 2具有较高的布氏酸性，从而提高了减压柴油催化裂化的轻油选择性。
To elucidate the migration process of cerium-cations and the resulting chemical diversification in cerium-NaY (Ce-NaY) ion-exchange processes, three calcination atmospheres (N2-atmosphere, O2-oxidation, N2-atmosphere followed by O2-oxidation) were adopted to study the influence of variable valence (III to IV) on ion migration, thermal stability, and catalytic activity. The results indicated that under N2-protection, significant amounts of Ce-(III) ions moved into the sodalite cage and increased the thermal stability of Ce-NaY. Under O2-oxidation, most Ce-(III) were converted to Ce-(IV) and remained inside the supercage. Ce-(IV) promoted water polarization and exhibited a unique hydroxyl group at 3582 cm−1in the infrared spectra. Ce ion-exchanged ultrastable Y zeolite (CeUSYO2) exhibited the highest amount of Brønsted acid due to the location of the Ce ions. Compared to CeUSYN2, CeUSYO2increased light oil selectivity in vacuum gas oil catalytic cracking due to its higher Brønsted acidity.
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影响因子：
4.3
作者：
Buurmans, Inge L. C.;Ruiz-Martinez, Javier;Weckhuysen, Bert M.
通讯作者：
Weckhuysen, Bert M.
影响因子：
7.3
作者：
L. A. Pine;P. Maher;W. A. Wachter
通讯作者：
L. A. Pine;P. Maher;W. A. Wachter
DOI：
10.1016/0927-6513(94)00061-y
发表时间：
1995
期刊：
Microporous Materials
影响因子：
--
作者：
M. Hunger;G. Engelhardt;J. Weitkamp
通讯作者：
M. Hunger;G. Engelhardt;J. Weitkamp
影响因子：
5.2
作者：
Guintar Luciano Baugis;H. Brito;W. D. Oliveira;F. Castro;E. Sousa-Aguiar
通讯作者：
Guintar Luciano Baugis;H. Brito;W. D. Oliveira;F. Castro;E. Sousa-Aguiar
DOI：
10.1021/j100858a046
发表时间：
1968-11
期刊：
The Journal of Physical Chemistry
影响因子：
--
作者：
J. W. Ward
通讯作者：
J. W. Ward