02213nas a2200241   4500008004100000022001400041245010500055210006900160260007300229300001000302490000800312520137700320653002001697653000801717653001301725653001501738653001101753100002201764700002001786700001801806700001801824856012901842       2013                        eng d  a1387-181100aCrystallization kinetics of Sn-MFI molecular sieve formation by dry gel cross mark conversion method0 aCrystallization kinetics of SnMFI molecular sieve formation by d  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcDEC  a73-800 v1823 a<p>The conversion of amorphous stannosilicate dry gel into crystalline molecular sieve with MFI structure (Sn-MFI) was achieved by dry gel conversion (DGC) method at 413, 443 and 473 K. For comparison purpose, Sn-MFI molecular sieve with similar SiO2/SnO2 mole ratio was also obtained by hydrothermal crystallization route. Crystallization curves were established by conducting time dependant studies on progressive crystallization processes for both the systems. The values of activation energy of nucleation (E-n), activation energy of crystallization (E-c), and their pre-exponential factors (InA(n), InA(c) respectively) were calculated from Arrhenius plots. Compared to the hydrothermal method, shorter induction period was observed when DGC method was employed. Both the E-n (49.70 kJ/mol) and E-c (52.82 kJ/mol) for DGC method were found to be lower than that of the E-n (55.70 kJ/mop and E-c (60.23 kJ/mol) for hydrothermal method. The kinetics parameters viz. K and q were derived from kinetic expressions and DGC method showed higher value of K and lower value of q compared to hydrothermal crystallization method at identical temperature. Various DGC method parameters such as water content at the bottom of autoclave and SiO2/SnO2 mole ratio have shown the influence on the kinetics of crystallization of Sn-MFI. (C) 2013 Elsevier Inc. All rights reserved.</p>10aCrystallization10aDGC10akinetics10aNucleation10aSn-MFI1 aNiphadkar, P., S.1 aTangale, N., P.1 aJoshi, P., N.1 aAwate, S., V.  uhttps://library.ncl.res.in/content/crystallization-kinetics-sn-mfi-molecular-sieve-formation-dry-gel-cross-mark-conversion-0