(629a) New Structure of Matter for High Performance Heterogeneous Catalytic VOC Oxidation At Short Contact Time

Wahid, S., Auburn University

A new class of composite materials, microfibrous entrapped catalyst (MFEC); prepared by traditional low cost paper making technique, entrap small (150-230 μm dia.) catalyst particulates Pd/ γ-Al2O3 into sinter-locked networks of metal (e.g. Ni) microfibers (8 μm dia.). This MFEC has uniform structure with high and variable voidages. MFEC with pleated configuration (Pleat number 4) enhances significant improvement to the pressure drop reduction and higher catalyst utilization. Also small particle of MFEC improves interphase and intraparticle mass transfer rate.  Ensuring comfortable environment in aircraft cabin and similar air handling devices is an issue to be concerned. To provide controlled and improved air quality, VOC removal, by catalytic combustion is of strong interest. Catalytic oxidation of VOC (i.e. n-hexane model compound) was investigated at typical face velocities (ca. 10 to 30 m/s) resulting intrabed/intralayer residence times from 30-200 µsec. This research focuses on unique structures of matter which attain high levels of VOC removal Pleated MFECs (˜3.2 mm) containing Pd/ γ-Al2O3 are tested at operating conditions similar to those used in air beneficiation. A conversion comparison of n-hexane by noble metal (Pd) and transition metal (Mn, Co) has been made at various flow rates (10 to 30 m/s) and temperature (100 to 200°C). Reaction kinetics and pressure drop comparison for different fiber dimension have also been studied using the experimental findings.