Surface Modification Of Zeolite Sieves And Its Alkylation Reaction Property

The 2,6-dialkylnaphthalene(2,6-DAN) is used as a main intermediate of 2,6-naphthalene dicarboxylic acid(2,6-NDCA) synthesis in the manufacture of high performance polyester resins of polyethylene naphthalene polymer(PEN),because 2,6-NDCA is easily oxidized to PEN,which has excellent gas barrier property,thermal and chemical stability ,as well as mechanical properties that will lead to its widely applications in such industry as electronics component, instrument appearance, fiber, insulate materials, film, food and bottle packing, aviation and atomic energy material.At present,the main reason restricting PEN industry is that the cost of 2,6- DAN production is too high, so choose an reasonable synthesis craft of 2,6-DAN, lowering its production cost is to be of great importance.In this article impregnation and chemical liquid deposition (CLD)methods are employes as main methods for surface modification of HY and Hβ zeolites,which will be aimed to improve the activity and selectivities of naphthalene alky lation. Through investigation on naphthalene alkylation performance with zeolites modified in different conditions as catalyst,the rules that how surface modification affects catalyst properties can be obtained,that is, surface modification doesn't affect the framework and inner environments of zeolites ,but only reduces its pore-mouth diameter and covers its surface acidity.At the same time, NH₃- TPD, XRD, Py- IR, and XRF, N₂ adsorption isotherm technique were carried to characterize its surface acidity and crystal structures before and after modification ,further explaining its modifying mechanism.1.Through studying of reaction conditions such as temperature,time and material mol ratio which influence naphthalene alkylation,the optimal conditions...