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采用四乙基氢氧化铵为模板剂，分别以铝酸钠和拟薄水铝石为铝源合成了β沸石，经硝酸铵溶液离子交换、柠檬酸处理及高温焙烧后制得Ｈβ沸石．采用ＮＨ３ＴＰＤ， 吡啶吸附态ＩＲ，２９Ｓｉ ＮＭＲ 及２７Ａｌ ＮＭＲ 技术研究了Ｈβ沸石的酸性位及脱铝与补铝过程． 结果表明，经柠檬酸处理后Ｈβ沸石酸强度减弱，总酸量增加，弱酸量增加的幅度大于强酸量增加的幅度，Ｂ酸量增加，Ｌ酸变化不明显． 柠檬酸处理具有脱铝与补铝的双重功能，脱铝可能主要发生在Ｓｉ（２Ａｌ） 位，补铝可能主要发生在Ｓｉ（０Ａｌ）Ｄ位．Ｈβ沸石的酸性及酸度与β沸石的合成条件、离子交换条件及酸处理条件密切相关，在一定的Ｓｉ／Ａｌ 比（１０～１５） 范围内， Ｈβ沸石的酸度决定于骨架硅的铝配位数及其分布．
With tetraethylammonium hydroxide as templating agent, β zeolite was synthesized by using sodium aluminate and pseudo-boehmite as aluminum source respectively, then Hβ zeolite was prepared by ammonium nitrate solution ion exchange, citric acid treatment and high temperature calcination. NH3 TPD, pyridine adsorption state IR, 29Si NMR and 27Al NMR techniques were used to study the acidic sites and the dealumination and aluminum removal processes of Hβ zeolites. The results showed that the acidity of Hβ zeolite was weakened and the total acidity increased after citric acid treatment. The amount of weak acid increased more than the amount of strong acid. The amount of B acid increased and the change of L acid was not obvious. The citric acid treatment has the dual functions of dealumination and aluminum addition. The dealumination may occur mainly at the Si (2Al) site and the supplementing aluminum may occur mainly at the Si (0Al) D site. The acidity and acidity of Hβ zeolite are closely related to the synthesis conditions, ion exchange conditions and acid treatment conditions of β zeolite. The acidity of Hβ zeolite depends on the aluminum coordination of the framework silicon at a certain Si / Al ratio (10-15) Number and distribution.