白庙子斜发沸石酸改性研究

Study on the Acidic Modification of the Baimiaozi Natural Clinoptilolite

用ＨＣｌ浸渍、ＮＨ４Ｃｌ浸煮改性白庙子斜发沸石，并采用化学分析、低温Ｎ２静态吸附、ＸＲＤ、ＦＴ－ＩＲ和ＴＧ－ＤＴＡ等手段对其表征。试验结果表明，上述改性引起晶胞体积收缩，热稳定性降低。ＮＨ４Ｃｌ浸煮骨架脱Ａｌ少，结晶度增高，微孔体积变大。ＨＣｌ浸渍骨架脱Ａｌ随酸度变化，结晶度降低，微孔体积减小。同时，配位Ｋ＋离子定位于平行ａ的八员环孔道中，比其他阳离子难脱除。Ｆｅ３＋以ＦｅＯ－４四面体参加到沸石骨架中。

Baimiaozi natural clinoptilolite was modified by treating with NH 4Cl heat immerson and HCl immerson.It was characterized by chemical analysis,XRD,IR,TG DTA and N 2 adsorption at 77K.It was found that the unit cell contracted and the thermal stability lowered after the modification.Treatment with NH 4Cl causes less framework dealumination,but enhances crystallinity and increases micropore volume.In the case of treatment with HCl,the framework dealumination changes with HCl concentration,with reduction in crystallinity and decrease in micropore volume.Meanwhile,K + ions of the coordinated framework of the zeolite are located in the 8 membered ring channels parallel to the axis,which are more difficult to remove than Ca 2+ ,Mg 2+ and Na + Fe 3+ ions in the clinoptilolite entered the zeolite framework in the form of FeO - 4 tetrahedra,the removal of which was more difficult than that of Al 3+ .