The "ship-in-bottle" catalyst NH^W-NaY was synthesized under microwave radiation and characterized by FTIR, XRD and low temperature N2 adsorption-desorption. HPW-NaY was produced from NR4PW-NaY by the in situ reaction of NE4PW with nitrogen oxides (NOx). FTIR and in situ pyridine adsorption IR confirmed that HPW-NaY with encaged HPW was prepared successfully for the first time. The NOx adsorption-desorption on HPW-NaY was investigated, and the results showed that 2.38 mgNOx· g-1 was adsorbed at 170 ℃, and the adsorbed NOX could be desorbed under cooling in wet air. After NOx desorption, the HPW-NaY could be reused without regeneration. Finally, temperature-programmed desorption coupled with mass spectroscopy (TPD-MS) was carried out on HPW-NaY filled with NO, to probe into its ability to catalyze NOx decomposition. O2 formation was observed, which lags a little behind the appearance of N2O and N2 on HPW-NaY. The NOx conversion is 61% with N2 selectivity of 75%, which is higher than that on pure HPW.%采用原位合成的方法,在微波辐射条件下制备了样品NH4PW-NaY,并通过FTIR、XRD、低温氮吸附-脱附等手段确认了该样品为磷钨酸铵(NH4PW)存在于NaY沸石超笼中的“瓶中船”型催化剂.通过NH4PW与NOx反应生成磷钨酸(HPW)的方式将NH4PW-NaY转化为HPW-NaY,并通过红外及红外吡啶吸附等表征手段证实了NaY沸石超笼中只含有磷钨酸的“瓶中船”型催化剂HPW-NaY被首次制备.随后研究了该催化剂对NOx的吸附-脱附性能,结果表明,在吸附温度为170℃时,HPW-NaY对浓度为1 696 mg·m-3的NOx吸附容量为2.38 mgNO·gcat-1,在通水蒸汽条件下,催化剂温度降至100℃时所吸附的NOx发生脱附,脱附后的催化剂可重复使用.最后通过程序升温脱附-质谱(TPD-MS)研究了HPW-NaY对NOx的催化分解性能,结果发现NOx在以NaY沸石为载体的HPW上的分解过程中有O2产生,且氧的产生滞后于N2O及N2,HPW-NaY催化分解NOx的转化率及N2选择性分别为61％与75％,均高于单纯HPW催化剂.
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