A novel hierarchical tungsten-substituted Silicalite-1 zeolite with the highly interconnected hollow structure (HWS-1) was synthesized for the first time by post-treating the purely microporous tungsten-substituted Silicalite-1 (WS-1) through simultaneous desilication and tungstation, in which a combination of sodium hydroxide and tetrapropyl ammonium hydroxide (TPAOH) was used to achieve a systematic balance between dissolution and recrystallization and further promote the synchronous tungstation with using sodium tungstate dihydrate as a tungsten source. Under an optimum addition ratio of NaOH/TPAOH, the resulted HWS-1 exhibited not only well retained microporosity and crystallinity but also obviously enlarged external surface area and mesopore volume in contrast to the parent WS-1. Furthermore, the effective tungstation also facilitated the substitution and increased the amount of coordinated W species in zeolite frameworks. The catalytic performance of HWS-1 was evaluated by the epoxidation of cyclohexene with using H₂O₂ as oxidant. Benefited by the highly interconnected hollow structure and more accessible active sites on the enlarged external surface, the HWS-1 catalyst revealed a higher catalytic activity with improved cyclohexene conversion than WS-1. Moreover, it was found that a significant positive effect on promoting epoxidation was achieved by tungsten-substituted Silicalite-1 (WS-1 and HWS-1) catalysts reflecting at a much higher selectivity of epoxide (>79%) in comparison with titanium-substituted Silicalite-1 (TS-1) (~50% selectivity of epoxide), due to their superior hydrophobicity and suitably weaker acidity, which further demonstrated the potential application of the developed hierarchical tungsten-substituted Silicalite-1 as a candidate catalyst for epoxidation and other selective oxidation reactions.

通过同时进行脱硅和钨丝化处理后，对纯微孔钨取代的Silicalite-1（WS-1）进行后处理，首次合成了具有高度互连的空心结构（HWS-1）的新型分级钨取代的Silicalite-1沸石。 ，其中使用氢氧化钠和氢氧化四丙铵（TPAOH）的组合来实现溶解和重结晶之间的系统平衡，并以二水合钨酸钠作为钨源进一步促进同步钨矿化。在最佳的NaOH / TPAOH加入比例下，与母体WS-1相比，所得HWS-1不仅具有良好的保留微孔性和结晶性，而且还具有明显增大的外表面积和中孔体积。此外，有效的钨极也促进了沸石骨架中的取代并增加了配位W物种的数量。HWS-1的环己烯环氧化反应用H来评价HWS-1的催化性能₂ O ₂作为氧化剂。得益于高度互连的中空结构和扩大的外表面上更易接近的活性位，HWS-1催化剂比WS-1具有更高的催化活性和改进的环己烯转化率。此外，发现用钨取代的Silicalite-1（WS-1和HWS-1）催化剂对促进环氧化具有显着的积极作用，与钛-钛相比，反映出更高的环氧选择性（> 79％）。取代的Silicalite-1（TS-1）（〜50％的环氧化物选择性），由于其优越的疏水性和适当的弱酸性，进一步证明了开发的分级钨取代的Silicalite-1作为环氧化候选催化剂的潜在应用和其他选择性氧化反应。