ABSORPTION OF GAS PHASE CONTAMINANT MIXTURES

将污染气体和蒸汽吸附到活性炭上是用于采样、室内空气清洁和呼吸保护的重要过程。 在使用这些应用的大多数环境中，气相污染物以低浓度存在，并且通常以混合物存在。 水蒸气在大多数环境中普遍存在，并且与气相污染物一起被吸附。 通常污染物本身代表气体、蒸气或两者的混合物。 当第二组分被共吸附时，吸附剂相对于气体或蒸汽的性能改变。 这一过程的程度尚未得到很好的记录或理解，特别是当混合物的成分以低浓度存在时。 拟议的研究将通过实验研究三种类型的活性炭的吸附能力的变化时，挑战与个别气体和蒸汽，以及低浓度的气相污染物的混合物。 在几乎所有情况下，第二种组分的存在都会降低碳的吸附能力，但本研究中会考虑一些值得注意的例外情况。 活性炭的吸附性能的变化将使用诸如吸附容量、吸附速率常数和吸附相的摩尔分数的参数来量化。 该研究还建议使用实验数据开发和验证简单，适用的模型，能够预测活性炭的性能，从单个组分的吸附数据的混合物的组分。 该项目的目标是：1）回顾文献中关于吸附研究和模型的信息，2）对选定的气相污染物混合物系统进行一系列吸附试验，以评估低浓度组分对吸附的影响，3）基于吸附性能与混合物中组分的各种参数之间的关系开发吸附模型。

Adsorption of contaminant gases and vapors onto activated carbon is an important process used for sampling, indoor air cleaning and respiratory protection. In most environments where these applications are used the gas phase contaminants are present in small concentrations and usually in mixtures. Water vapor is ubiquitous in most environments and is adsorbed together with the gas phase pollutant. Often the pollutant itself represents a mixture of gases, vapors, or both. The performance of the adsorbent respective to a gas or vapor is changed when a second component is co-adsorbed. The extent of this process is not yet well documented or understood, especially when the components of the mixture are present in low concentrations. The proposed research will experimentally investigate the changes in the adsorption capacity of three types of activated carbon when challenged with individual gases and vapors, and with low concentration gas phase contaminant mixtures. In almost all cases the presence of a second component will diminish the adsorption capacity of the carbons, with some notable exceptions which will be considered in this study. The changes in the adsorption performances of activated carbons will be quantified using parameters such as adsorption capacity, adsorption rate constant and mole fraction of the adsorbed phase. The research also proposes to use the experimental data in the development and validation of simple, applicable models able to predict the performance of the activated carbon for the components of a mixture from individual component adsorption data. The goals of the proposed project are to 1)review the literature for information on adsorption studies and models, 2)conduct a series of adsorption tests on selected gas phase contaminant mixture systems to assess the impact of low concentration components on the adsorption, 3)develop adsorption models based on the relationship between the adsorption performances and various parameters of the components in the mixture.