Research Assistant Professor
Colorado State University
Dr. Blotevogel is a Research Assistant Professor in the Department of Civil & Environmental Engineering at Colorado State University (CSU). He holds a PhD in Environmental Chemistry from CSU and a Diploma in Environmental Engineering from the Technical University Berlin, and has worked three years as consultant for in situ groundwater remediation.
Dr. Blotevogel’s research interests revolve around the fate of new and emerging contaminants, conducting laboratory- and field-scale experiments to elucidate degradation in both natural and engineered systems. He has developed sustainable water treatment technologies, theoretical models for contaminant degradation pathways and kinetics, as well as various advanced analytical techniques with a focus on transformation products and complex mixtures. He is currently working on solutions for managing per- and polyfluoroalkyl substances (PFAS), 1,4-dioxane, pesticides, perchlorate, polar hydrocarbons, and oil & gas produced water.
Incineration of Perfluoroalkyl Carboxylic Acids: A Thermal Stability Ranking Among Common Organic Chemicals
Jens Blotevogel1, Robert Giraud2,3, Anthony K. Rappé4
1 Department of Civil and Environmental Engineering, Colorado State University, Fort Collins, CO 80523, USA
2 The Chemours Company, Wilmington, DE 19899, USA
3 Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, DE 19716, USA
4 Department of Chemistry, Colorado State University, Fort Collins, CO 80523, USA
Thermal treatment processes are currently the only option for the destruction of per- and polyfluoroalkyl substances (PFAS) in large waste streams. Due to the lack of robust data on thermal PFAS decomposition, concerns about the formation and emission of products of incomplete combustion (PICs) exist. To determine the required conditions for safe incineration, we performed uniquely accurate quantum chemical simulations to assess the thermal decomposition pathways and kinetics of perfluorooctanoic acid (PFOA) and its replacement hexafluoropropylene oxide dimer acid (HFPO-DA). Considering all relevant thermal decomposition mechanisms, we calculated temperatures at 2 second gas residence time indicative of 99.99% destruction and removal efficiency (DRE) for full-scale incineration. Our findings show that incineration of these two perfluoroalkyl carboxylic acids (PFCAs) requires substantially lower temperatures than several other organic compounds that are being incinerated on a regular basis. No increase in required incineration temperature was observed with decreasing length of the perfluoroalkyl chain, indicating a low potential for PIC accumulation under the right conditions. However, as some decomposition processes were found to be concentration-dependent, waste stream composition plays a key role in thermal decomposition rates. Collectively, our findings will provide critically missing information to ensure safe, cost-efficient, and complete destruction of PFCAs during thermal treatment.