氧化物对Hβ沸石催化行为的影响

Study on Catalytic Behavior of Hβ Zeolite Modified by Oxides

用ＸＲＤ、ＸＰＳ、ＮＨ＿３－ＴＰＤ、ＦＴ－ＩＲ及化学吸附等手段研究了负载Ｂ＿２Ｏ＿３、Ｆｅ＿２Ｏ＿３等氧化物对Ｈβ沸石表面酸性和丙烯醚化反应性能的影响．结果表明：负载的Ｂ＿２Ｏ＿３、Ｆｅ＿２Ｏ＿３与Ｈβ－Ａｌ＿２Ｏ＿３沸石间有较强的相互作用，Ｂ和Ｆｅ的化学环境有明显改变；氧化物调变了Ｈβ－Ａｌ＿２Ｏ＿３沸石的酸性，使总酸量增加，强酸中心强度下降，Ｌ酸中心比例提高；氧化物使丙烯醚化反应活性增强，抑制了异丙醇脱水反应；丙烯转化率与催化剂表面Ｌ酸量存在很好的对应关系。

The effect of B_2O_3 and Fe_2O_3 on the surface acidity and propylene etherificationwith isopropanol to isopropyl ether has been investigated by XRD, XPS ,NH_3-TPD, FT-IRand chemisorption.These impregnated oxides played a great role in modifying the total sur-face acid amount and distribution of acid strength.The stronger interaction between oxidesand Hβ-Al_2O_3 enhanced the L acid amount.Meanwhile,the performance of propylene etheri-fication was obviously improved.A good relationship between propylene conversion and sur-face L acid amount was detected.