کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
6453258 | 1418501 | 2017 | 9 صفحه PDF | دانلود رایگان |
- TPAOH VPT modification of structured ZSM-5/SiC foam catalysts.
- Effective conversion of aluminosilicate binder to zeolitic phase by TPAOH vapor.
- Enhanced catalytic performance of VPT modified ZSM-5/SiC foam catalyst in MTP reaction.
- Intrinsic properties of SiC foam are beneficial to MTP process.
Tetrapropylammonium hydroxide (TPAOH) was introduced in the vapor phase to perform the vapor-phase transport (VPT) modification of the structured ZSM-5 supported on SiC foam (ZSM-5/SiC foam) catalyst. An optimum precursor concentration of 0.5 M TPAOH could effectively convert the amorphous aluminosilicate binder to the zeolitic phase with improved intracrystal mesopores, nanosized crystals (ca. 100 nm), high concentration of acidity sites (83 mmol gâ1) as well as a high value of the relative acidity (0.7). Combined with the intrinsic property of macroscopic SiC foams such as the low pressure drop and the high thermal conductivity (14 W mâ1 Kâ1 at 773 K), TPAOH VPT modified ZSM-5/SiC foam catalyst demonstrated an excellent activity in the catalytic methanol-to-propylene (MTP) reaction, surpassing the state-of-the-art hierarchal ZSM-5 monolith catalyst. The catalyst showed an extended activity for ca. 970 h (>95% methanol conversion) with the high selectivity to the propylene (>45%). The coke formation was significantly retarded (ca. 2.1 Ã 10â2 wt.% hâ1) due to the enhanced transport phenomena within the developed structured catalyst.
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Journal: Applied Catalysis A: General - Volume 545, 5 September 2017, Pages 104-112