Synthesis of hydrophobic nanosized hierarchical titanosilicate-1 zeolites by an alkali-etching protocol and their enhanced performance in catalytic oxidative desulphurization of fuels
Synthesis of hydrophobic nanosized hierarchical titanosilicate-1 zeolites by an alkali-etching protocol and their enhanced performance in catalytic oxidative desulphurization of fuels
复制标题
碱蚀法合成疏水性纳米多级钛硅酸 1 型沸石及其在燃料催化氧化脱硫中的增强性能
DOI：
10.1016/j.apcata.2021.118466
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发表时间：
2022-01-25
影响因子：
5.5
通讯作者：
Hua, Zile
中科院分区：
文献类型：
--
作者：
Li, Linghao;Wang, Wei;Hua, Zile
采用水蒸汽辅助干凝胶转化法合成微孔TS-1分子筛，再经碱蚀处理形成中孔，通过简单的两步反应合成了不同Ti掺杂量的纳米级Ti-Si-1分子筛（nanoTS-1_D）。XRD、N2吸附等温线、DLS、UV-Vis、SEM、TEM和水滴接触角等表征结果表明，合成的纳米TS-1_D材料不仅具有丰富的晶内介孔和高比表面积，而且保持了微孔TS-1分子筛固有的表面疏水性。因此，它们在大体积环己烯/环辛烯环氧化和苯酚羟基化探针反应中表现出预期的上级催化性能，与微孔TS-1和无定形TiMCM-41介孔对应物形成对比。在燃料氧化脱硫中，它们对噻吩及其大体积衍生物的脱除率为100%，并具有良好的回收性能。此外，一个新的钛掺杂剂定向碱蚀刻机制已被提出来说明高比表面积nanoTS-1_D的合成。
Nanosized hierarchical titanosilicate-1 zeolites (nanoTS-1_D) with variable Ti doping content were synthesized by a simple and sequent two-step procedure consisting of microporous TS-1 nanocrystal synthesis through steamassisted dry-gel conversion and post alkali-etching treatment for mesopore formation. Comprehensive characterizations, e.g. XRD, N2 sorption isotherms, DLS, UV-Vis, SEM, TEM and water-droplet contact angle, indicated that the resultant nanoTS-1_D materials not only possess abundant intracrystal mesopores and high surface area, but importantly maintain the intrinsic surface hydrophobicity as those of microporous TS-1 zeolites. Consequently, they showed the expected superior catalytic performance in both bulky cyclohexene/cyclooctene epoxidation and phenol hydroxylation probe reactions, contrast to the microporous TS-1 and amorphous TiMCM-41 mesoporous counterparts. In the oxidative desulfurization of fuels, they exhibited 100% removal ability for thiophene and its bulky derivatives and excellent recyclability. In addition, a new Ti-dopant directed alkali-etching mechanism has been proposed to illustrate the synthesis of high-specific-surface-area nanoTS-1_D.