| ZSM-5 zeolite is a kind of mesothyrid zeolite, and its aperture is only about 0.6nm.Though it can be used in different catalytic reactions(catalytic cracking, molecular rearrangement, intermolecular coupling, carbon-carbon bond formation, isomerization etc), when the reactant or the product molecule's size dimension is greater than the aperture of the molecular sieve, the catalytic reaction will be limited. Therefore, to exploit ultramicro ZSM-5 zeolite, and use the double pore space(internal pore and intergranular pore) to meet the general and even the macromolecule catalytic reactions.Generally, the synthesis of ZSM-5 zeolite need some organic amines as templating agents. The organic amines are expensive and poisonous, they are harmful to researchers, so they are gradually replaced by inorganic ammonia in the process of synthesizing ZSM-5 zeolite. In the experiment, the conventional hydro-thermal synthesis method is adopted to synthesize ultramicro ZSM-5 zeolite. By using a series of chemical agents, they are Na2SiO3·9H2O, Al2(SO4)3·18H2O, concentrated H2SO4, NH3·H2O and ammonia respectively. By choosing different experiment conditions, such as temperature, time and the ratio of SiO2 to Al2O3. The samples are characterized by the methods of XRD, SEM, IR, TG-DTA, Laser size distribution and adsorption mass mensuration. Meanwhile, the samples are compared with those synthesized using ethylenediamine(EDA) as templating agents,. At last, the adsorption results are fitted by using mathematical mode.The experimental results show that the optimal synthesis conditions are: NH3-H2O as templating agents, crystallization temperature is 120℃, crystallization time is 8 days and the reactant ratio is 60SiO2:Al2O3:1800H2O:23NH3. SEM results indicate that the samples are crystal products and the granularities are small. The maximal adsorption mass to benzene and NH4+ are 739.2 mg/g and 33.2mg/g respectively. The fitting results reveal that the adsorption...
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