02121nas a2200241   4500008004100000022001400041245009900055210006900154260007300223300001200296490000700308520126100315653002101576653002501597653002701622653001101649653001301660653002501673100002301698700001501721700001801736856012501754       2006                        eng d  a0167-577X00aHydrothermal synthesis of MCM-41 using differently manufactured amorphous dioxosilicon sources0 aHydrothermal synthesis of MCM41 using differently manufactured a  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcAPR  a957-9610 v603 a<p>The influence of differently manufactured amorphous dioxosilicon sources such as fumed silica (FS), spray dried precipitated silica (PSI) and flash dried precipitated silica (PS,) on the course of structural development and properties of hydrothermally prepared siliceous MCM-41 phases have been investigated. Powder XRD, N-2 adsorption/desorption and scanning electron microscopy techniques were used for sample characterization. On the basis of results obtained from time dependent study on the progressive development of MCM-41 mesophases, the reactivity trend of dioxosilicon sources observed was as: FS &gt; PS1 &gt; PS2. MCM-41 synthesized using least expensive PS2 having less surface area has exhibited thicker pore walls but poor orderness, while MCM-41 prepared from expensive FS having high surface area has thinner pore walls and was well ordered. The extent of contraction caused by calcination, magnitude of the wall thickness and structural stability were found to be dependent on manufacturing process of dioxosilicon sources. The noticeable morphological differences were also observed by variations in the type of dioxosilicon sources used in the hydrothermal synthesis MCM-41 materials. (c) 2005 Elsevier B.V. All rights reserved.</p>10aCharacterization10adioxosilicon sources10aHydrothermal synthesis10aMCM-4110aporosity10aStructural stability1 aGaydhankar, T., R.1 aSamuel, V.1 aJoshi, P., N.  uhttps://library.ncl.res.in/content/hydrothermal-synthesis-mcm-41-using-differently-manufactured-amorphous-dioxosilicon-0