RECYCLING A PALYGORSKITE AND MONTMORILLONITE MEDIUM FOR THE PURPOSE OF REMOVAL OF CARBAMAZEPINE IN WATER RESOURCES

Pharmaceutical pollution in water resources is a major problem that has arisen from the inability of wastewater treatment plants to effectively remove pharmaceutical compounds. Trace amounts of pharmaceuticals derived from wastewater are believed to have negative impacts on human and ecological health, and studies have shown that many people and ecosystems are at risk for chronic low-level exposure. There are a variety of processes that are being studied to remove pharmaceuticals from wastewater that have a variety of advantages and disadvantages. This study focuses on adsorption by clay minerals as a low cost method to effectively remove the pharmaceutical carbamazepine. The minerals palygorskite and montmorillinite are ideal for this study owing to several properties and previous work has shown great potential for these minerals as reactive media for the removal of pharmaceuticals, including carbamazepine. One challenge in the implementation of these minerals is that large volumes of waste would be produced once the sorption sites are reacted and the media has reached the end of product life. In a previous investigation, a mixture of palygorskite and montmorillinite was heated to determine the effects of heat treatment on the clay and it was determined that there were no major mineralogical or structural changes due to heating that would prevent this material from being recycled. The possibility to recycle the palygorskite and montmorillonite medium by reheating and driving off adsorbed carbamazepine molecules to restore sorption sites was investigated. Batch sorption experiments were utilized to get an understanding of whether sorption sites are restored after heat treatment to allow material to be reused. The sorption capacity was measured after each recycling to determine if and how sorption capacity changed with use and will allow for a model of the performance life of the material to be created.