MODIFIED CLAYS FOR SORPTION AND CATALYTIC DEGRADATION OF VOCS

蒙皂石粘土的独特性质在设计中很重要 有效的吸附剂和催化剂是(1)高比表面积(2)高 阳离子交换容量(3)粘土小片的膨胀特性 (4)高表面酸性和高活性。这样的特性使得这些 材料具有内在的活性，并允许极大的合成多功能性 生产出具有特定解毒性能的结构。我们的目标 就是开发一种可用于处理液体废物的新型材料 其中污染物首先固定在粘土材料上，并且 然后通过在粘土表面的催化作用进行解毒。以粘土为基础的 为此目的而开发的材料有(1)过渡金属 饱和粘土(2)有机金属粘土(3)柱状粘土和(4) 剥离的粘土。另一个目标是开发和使用有机- 粘土作为粘土屏障的组成部分(例如，膨润土浆墙)以 完善垃圾处理库围堵特性。 金属粘土是一种用途广泛的催化剂，可用于生成活性物质。 有机毒物的自由基阳离子，如三氯乙烯、苯、二恶英和 酚类。这些活性自由基物种是各种 潜在的反应，以形成毒性较低的产品。重要反应，如 因为已经实现了聚合和脱氯。有机阳离子 也可以放置在蒙脱石粘土的表面以赋予疏水性 吸附痕量有机污染物的重要性质 含水的溪流。所需的吸附和催化性能可以是 通过使用有机阳离子和金属阳离子的混合物进行组合。有柱子的和 剥离粘土是微孔到大孔的衍生物，由 天然粘土与强健的聚氧离子的反应。相对的 这些粘土的大孔径使它们成为大型 氯代烃。此外，金属催化剂还可以引入到 它们的结构有助于吸附的分子随后的氧化 毒药。

The unique properties of smectite clays that are important in designing effective adsorbents and catalysts are (1) high surface area (2) high cation exchange capacity (3) swelling properties of the clay platelets and (4) high surface acidity and reactivity. Such properties make these materials inherently reactive and allows tremendous synthetic versatility to produce structures have specific properties for detoxication. Our goal is to develop a new class of materials useful for treating liquid wastes in which the contaminant is first immobilized on the clay material and then detoxified via catalysis on the clay surface. The clay-based materials being developed for this purpose are (1) transition metal saturated clays (2) organo-metal-clays (3) piliared clays and (4) delaminated clays. An additional objective is to develop and use organo- clays as components of clay barriers (e.g., bentonite slurry walls) to improve the containment characteristics of waste disposal reservoirs. Metal clays are versatile catalysts which can be used to form reactive radical cations of organic toxicants such as TCE, benzene, dioxins and phenols. These reactive radical species are subject of a variety of potential reactions to form less toxic products. Important reactions such as polymerization and dechlorination have been achieved. Organic cations can also be placed on the surface of smectite clays to impart hydrophobic properties important for adsorption of trace organic contaminants from aqueous streams. The desired sorptive and catalytic properties can be combined by using a mixture of organic and metallic cations. Pillared and delaminated clays are microporous to macroporous derivatives formed by the reaction of natural clays with robust polyoxocations. The relatively large pore sizes of these clays make them ideal adsorbents for large chlorinated hydrocarbons. Also, metal catalysts can be introduced into their structures to facilitate subsequent oxidation of the adsorbed toxicant.