| Zeolitic microporous materials are an important part of our everyday life. They are utilized in detergents to soften water through an ion exchange mechanism and as a catalyst to crack crude oil into more desirable fuel sources as well as for a variety of other purposes. Methods for creating new microporous materials, increasing yields and the purity and understanding the mechanisms by which they form are being studied. A low temperature growth of faujasitic zincophosphate (ZnPO-X) is reported here that implicates a preexisting structure of DABCO-phosphate when the templating agent DABCO and the phosphorus-containing source (H3PO4) are mixed prior to adding a zinc source. DABCO-phosphate crystals have been isolated and when they are utilized for zincophosphate growth, the reaction produces nearly pure ZnPO-X crystals. Hopeite, a condensed zincophosphate, is the preferential product when the reactant species are mixed in a different order that does not combine the DABCO and phosphate sources as a precursor. Also reported is a microwave irradiated reverse micellar growth of ZnPO-X. If a short microwave burst (1 minute at 150 W) is introduced during the nucleation stages of a 48-hour synthesis procedure, P6, an impurity, is the primary product. At later stages in the growth, after the initial 4-hour nucleation stage, competition between ZnPO-X and P6 leads to a mixed product. When the short microwave pulse is added to the reaction after complete crystallization, or after about 15 hours, ZnPO-X growth is promoted and increased yields are noted. A microwave irradiated reverse micellar gold nanoparticle growth by the reduction of HAuCl4 with hydrazine hydrate was studied as a model of microwave irradiated reverse micelle growth. |
