Synthesis of high alumina ZSM -5 molecular sieve with ethylene diamine as template

Catalysis Division, National Chemical Laboratory, Pune-411 008, Maharashtra, India

E-mail : venkat@cata.ncl.res.in Fax : 91-20-25893761

Manuscript received 15 February 2005, revised 14 November 2005, accepted 6 April 2006

Attempts were made to investigate compositional constraints in the synthesis of pentasil molecular sieves, Including aluminosilicate zeolites usiug ethylene diamine (C₂DN) template, from the gel composition 1.85Na₂O : aAl₂O₃:15.2SiO₂: 592H₂O :19.7C₂DN in the temperature 177 ºC for ten days. When \(a\) = 0.25 the product was ZSM-5 and then \(a\) =1 the product was ZSM-35 and in hctm:eu compositions tile mixture of two were obtained. Reduce the time or crystallization time to 5 days give mmncrystalllne material. XRD and Ff ·IR spectra in framework region of ZSM-5 synthesized using ethylene diamlne template and without template are having similar pattern, however the intensity varies. Scanning electron microscopic picture of the both are varies. The structural stability or the uolite ZSM-5 synthesized using no template was also found to be lower as compared with that for the ZSM-5 synthesized using ethylene diamine template. These differences may result from the occluded excess sodium.