Catalytic Combustion of Waste Halogenated Solvents

一种新的制备方法被应用于稀薄气流中卤素氧化催化剂。该工艺用不锈钢筛生产高活性的氧化/还原催化剂，能抵抗反应产物HCl的侵蚀，表现出良好的稳定性和选择性。将发展对制备变量、初级反应动力学和潜在的失活限制的机械论见解。应阐明催化剂活性与表面形态变化之间的新关系，这些变化在电子探针和显微镜图像中明显。如果存在于地下水或空气中，氯化碳氢化合物(CHCs)会对健康造成严重威胁。焚烧可以将它们转化为HCl，然后在洗涤操作中将其中和。与这项技术相关的两个困难是：如果废气具有足够低的热值，则需要添加大量辅助燃料，以及可能产生不完全燃烧的令人不快的产品。催化氧化提供了从CHC到HCl+CO2的另一种途径，在保持催化剂活化温度并避免中毒的情况下，是稀烃混合物的理想选择。研究将集中在最后两个要求上。催化剂将通过欧姆加热来保持温度，并通过合理选择活性催化剂来避免中毒。

A novel preparation method has been adapted to a catalyst for oxidation of halogens in dilute air streams. This procedure produces a highly active oxidation/reduction catalyst from stainless steel screen, which is resistant to the attack by the reactor product, HCl, and exhibits good stability and selectivity. Mechanistic insights into the preparation variables, primary reaction kinetics, and potential deactivation limitations will be developed. New relationships should be elucidated between catalyst activity and surface morphology changes evident in electron microprobe and microscope patterns. Chlorinated hydrocarbons (CHCs) represent a serious health risk if present in groundwater or the air. Incineration can be used to convert them to HCl, which can then be neutralized in a scrubbing operation. Two difficulties are associated with this technology: the requirement of adding significant amounts of auxiliary fuel if the waste stream has a sufficiently low heating value, and the possibility of creating unsavory products of incomplete combustion. Catalytic oxidation provides an alternative route from CHC to HCl plus CO2, and is ideal for dilute hydrocarbon mixtures provided the catalyst activation temperature is maintained and poisoning can be avoided. Research will concentrate on these last two requirements. The temperature of the catalyst will be maintained by ohmic heating, and poisoning will be avoided by a judicious selection of the active catalytic agent.