MgCoAPO-5和MnCoAPO-5分子筛的合成、结构及其性能研究

以三乙醇胺作模板剂,用水热法合成了 MgCoAPO-5和 MnCoAPO-5分子筛。X 射线衍射、红外光谱和电子探针等研究结果及化学组成分析表明,Mg、Co,Mn、Co 同时进入 AlPO_4-5 分子筛骨架而未改变结构类型。同时对这两种分子筛的晶体形貌、吸附性能、热稳定性进行了研究,测定了 AlPO_4-5,MgCoAPO-5,MnCoAPO-5,HZSM-5对异丙苯裂解反应的催化活性,并用吡啶中毒法测定了它们的表面酸性,发现 AlPO_4-5对此反应无活性,而 MgCoAPO-5和 MnCo-APO-5有良好的活性,尤其是 MgCoAPO-5的催化活性接近于 HZSM-5。

Synthesis,Structure and Properties of MgCoAPO-5 and MnCoAPO-5 Molecular Sieves

Two novel kinds of crystalline microporous metal aluminophosphate molecular sieves,magnesium cobalt aluminophosphate(MgCoAPO-5)and manganese cobalt aluminophosphate(MnCoAPO-5),were synthesized by hydrothermal crystallization method.The results of X-ray diffraction,infrared spectra,electron probe energy dispersion analysis,and chemical composition of MgCoAPO-5 and MnCoAPO-5 indi- cated that Mg,Co or Mn,Co entered the framework of AlPO_4-5 molecular sieve without disrupting the microporous framework.Properties of MgCoAPO-5 and Mn- CoAPO-5 such as crystal morphology,thermal stability,adsorption properties, catalytic activity towards cumene cracking reaction,and surface acidity have been studied.The results show that MgCoAPO-5 and MnCoAPO-5 possess much higher acidity and catalytic activity than the unmodified AlPO_4-5.