Pt/PTA-MIL-101(Cr)的合成及其正庚烷异构催化性能

石油炼制与化工 ›› 2022, Vol. 53 ›› Issue (1): 68-75.

Pt/PTA-MIL-101(Cr)的合成及其正庚烷异构催化性能

刘荣江¹,马守涛^1,2,姜震¹,张微¹,崔艳红^1,3,刘金艳¹,所艳华¹,汪颖军¹

1. 东北石油大学化学化工学院
2. 中国石油石油化工研究院大庆化工研究中心
3. 黑龙江八一农垦大学测试中心农业农村部农产品及加工品质量监督检验测试中心（大庆）

收稿日期:2021-03-08 修回日期:2021-10-09 出版日期:2022-01-12 发布日期:2021-12-24
通讯作者: 张微 E-mail:99095871@qq.com
基金资助:
东北石油大学“国家基金培育”基金

SYNTHESIS OF Pt/PTA-MIL-101(Cr) AND ITS CATALYTIC PERFORMANCE FOR n-HEPTANE ISOMERIZATION

Received:2021-03-08 Revised:2021-10-09 Online:2022-01-12 Published:2021-12-24

摘要/Abstract

摘要： 使用磷钨酸(PTA)对金属有机骨架材料MIL-101(Cr)进行改性，制备了0.4%Pt/PTA-MIL-101(Cr)催化剂，并首次应用于正庚烷异构化反应。通过对样品进行一系列表征，得出以下结论：所合成的样品为介孔-微孔复合材料，具有正八面体结构，孔道结构规整有序，比表面积高；掺杂PTA后，未破坏MIL-101(Cr)的骨架结构和热稳定性；PTA在催化剂中仍可保持其Keggin结构，可为催化反应提供良好的酸性环境；Pt在MIL-101(Cr)中的分散度较高。通过正庚烷异构化反应对催化剂性能进行评价，得出在PTA掺杂量(w)为30%、反应温度为260 ℃时，催化剂的酸性位点与金属位点的匹配度最适宜催化庚烷异构化反应，此时催化剂上正庚烷转化率与异庚烷选择性分别可达69.1%和93.7%。

关键词: MIL-101(Cr), 磷钨酸, 铂, 正庚烷, 异构化

Abstract: The 0.4%Pt/PTA-MIL-101(Cr) metal-acid bifunctional catalysts with different doping amounts of PTA were prepared by modifying organometallic skeleton material MIL-101(CR) with phosphotungstic acid (PTA) and were first applied to n-heptane isomerization. The synthesized samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), N2 adsorption-desorption, thermal gravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR), X-ray fluorescence (XRF) and acid-base titration. The results show that the synthesized samples are mesoporous-microporous composite materials with typical octahedral structure, regular pore structure and high specific surface area; the framework and thermal stability of MIL-101(Cr) are not damaged; the Keggin structure of PTA can be maintained in the catalyst, which can provide a good acidic environment for the catalytic reaction and the higher dispersity of Pt in MIL-101(Cr). Through the evaluation of n-heptane isomerization performance of the catalyst, it was found that the best match between the acid sites and metal sites of the catalyst was the most suitable for catalyzing n-heptane isomerization, when the reaction temperature was 260 ℃ and the doping content of PTA was 30%, and the conversion of n-heptane and the selectivity of iso-heptane could reach 69.1% and 93.7%,respectively.

Key words: MIL-101(Cr), phosphotungstic acid, platinum, n-heptane, isomerization

刘荣江马守涛姜震张微崔艳红刘金艳所艳华汪颖军. Pt/PTA-MIL-101(Cr)的合成及其正庚烷异构催化性能[J]. 石油炼制与化工, 2022, 53(1): 68-75.

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