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Methyl Tertiary-Butyl Ether (MTBE) contamination of groundwater and surface waters has become a relevant environmental and public safety concern in recent years. This anthropogenic compound is now persistent at low concentrations in several valuable ground and surface water locations within the United States due largely to the widespread production of MTBE for use as a fuel oxygenate in conjunction with negligent underground storage practices during the 1980's and 1990's. Though there are several treatment strategies for the remediation of MTBE spill sites, the most efficient strategy may be adsorption of MTBE by a packed column of silicalite-1 adsorbent. Effective adaption of this technology requires cheap production of silicalite-1 sorbent packing particles on the order of 3 millimeters diameter. This work entails the development of a new synthesis process which results in sufficient in-situ crystallization of silicalite-1 aggregates within a 3 millimeter spherical amorphous silica gel source. The crystal aggregates sizes can be tuned from 5 to 70 µm, depending on synthesis parameters, and the finished silicalite-1 aggregate particle takes the shape of the amorphous gel source. These aggregate particles, when containing a small amorphous core, should be suitable for packed adsorption column applications. Multiple hydrothermal synthesis experiments were performed by batch methods featuring silica gel spheres as the sole silica source for the batch. Zeolite nucleation and crystal growth were demonstrated throughout the amorphous bead. Synthesis parameters were optimized both for short synthesis times, optimal mechanical properties, and cost effectiveness. The influence of product crystal size on particle hardness was also investigated. The packing production process is sufficiently ready for supporting pilot scale adsorption studies.

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Fluidised cracking catalysts, which contain a form of zeolite-Y as the main catalytically active component, are widply used commercially for the conversion of crude oil into more profitable product streams. During the cracking reaction, these catalysts are contaminated with vanadium which has a marked effect on the crystallinity of the zeolite-Y component and, as a consequence, activity and selectivity for hydrocarbon processing is degraded. The purpose of this work has been to carry out a detailed investigation, on the laboratory scale, of the effect of vanadium contaminatioil on both commercial and model rare earth ion-exchanged zeolite-Y catalysts. Vanadium contamination was achieved using a standard (Mitchell) method and catalysts were subject to treatment conditions similar to those found in the regenerator part of a fluidised catalytic cracking unit using a specially constructed furnace. Investigations of the solid state chemical reactions between vanadium and rare earth compounds, both in the presence and absence of silica and alumina support materials typical of those found in commercial catalysts, extend the study. Extensive use is made of magic-angle-spinning nuclear magnetic resonance spectroscopy (5 IV and 27AI), X-ray powder diffraction and surface area measurements for sample characterisation. The apparatus for surface area measurements was constructed during the course of the work. It is suggested that the reduction in crystallinity of rare earth ion-exchanged zeolite-Y in the presence of vanadium is associated with the removal of rare earth ions from the cage structure of the zeolite. The extent of this process depends upon the details of the treatment conditions and important factors are identified. The observation of the formation of LaV04 in a range of hydrothermally treated lanthanum ion-exchanged zeolite-Y samples supports the proposed model.