AAAR 34th Annual Conference
October 12 - October 16, 2015
Hyatt Regency
Minneapolis, Minnesota, USA
Abstract View
Optimizing Design for Oxidative Flow Tube Reactors
DHRUV MITROO, Yujian Sun, Boung Wook Lee, Andrew Lambe, William Brune, Brent Williams, Washington University in St. Louis
Abstract Number: 524 Working Group: Instrumentation and Methods
Abstract Oxidative flow reactors (OFRs) have gained popularity in recent years as a laboratory means of studying secondary organic aerosol (SOA) formation, and the oxidation of primary aerosols during heterogeneous reactions with ozone or OH radicals. These reactors are designed for a high degree of conversion of starting material in a short residence time, while avoiding significant wall losses. Can we do a better job of operating OFRs to allow for the highest and most uniform exposure possible, based on kinetic properties of starting material such as reaction rate constants?
Here, we look at geometry configurations and operating conditions such as flowrate and wall temperature for compounds of different reactivity to OH to determine if there is an optimal residence time distribution (RTD) for the study of these compounds with the Potential Aerosol Mass (PAM) reactor, an OFR. If the RTDs are compared to the characteristic reaction time (e.g., short reaction time for terpenes vs. long reaction time for primary soot particles with OH), a different flowrate or different wall temperature may be chosen, as well as different inlet configurations (e.g., presence of an inlet sparger or short honeycomb segment for flow dispersion and stabilization). For heterogeneous reacting systems, such properties maybe of importance since the process may be either reaction or transport limited. A common limitation of OFRs, whilst studying heterogeneous chemistry, is that the short physical residence time does not allow the study of mass-transfer effects to reactive uptake. With an appropriate design and full characterization, we can suggest appropriate operation parameters (e.g., flowrates and wall temperatures) to the community to study SOA formation vs. heterogeneous chemistry in OFRs.