使用四乙基氢氧化铵作为有机模板剂和常规硅铝源直接合成SSZ-13沸石分子筛

使用四乙基氢氧化铵作为有机模板剂, 利用常规铝源和硅源而不需要高硅Y沸石作为起始原料, 同时加入适量的沸石晶种直接合成了SSZ-13沸石分子筛. 所合成的沸石产物结晶度好, 具有良好的水热稳定性, 并在氨选择性催化还原(NH₃-SCR)反应中显示出优异的催化性能, 为其在工业上广泛应用提供了可能.

Direct Synthesis of SSZ-13 Zeolite Using Tetraethylammonium Hydroxide as an Efficient Organic Template in the Presence of Conventional Aluminum and Silicon Sources†

High silica CHA zeolite(SSZ-13) has been commercially applied in selective catalytic reduction of NO_x with ammonia currently, but the use of costly organic templates of N,N,N-trimethyl-adamantammonium hydroxide(TMAdaOH) in the synthesis strongly limits its industrial application. To solve this problem, it is developed a synthetic route using relatively low-cost organic templates such as tetraethylammonium hydroxide(TEAOH), but in this case it is necessary to use costly high silica Y zeolite as a starting source. In this report, we for the first time show that SSZ-13 zeolite could be synthesized directly from conventional silicon and aluminum sources using TEAOH as an efficient organic template by carefully adjusting the starting gels in the presence of SSZ-13 seeds. The obtained aluminosilicate SSZ-13 product has good crystallinity, uniform crystals, and excellent hydrothermal stability. Furthermore, copper-exchanged SSZ-13 zeolite has excellent catalytic performance in NH₃-SCR reaction before and after hydrothermal treatment. The combination of good catalytic performance with low-cost synthesis offers a good opportunity for wide applications of this zeolite in the future.