A TiO2-coated rotating corrugated reactor is experimentally characterized and simulated for ultraviolet (UV)-based photo degradation of methylene blue (MB). Using degradation kinetics derived from flat-plate experiments and finite-element discrete-ordinate models simulating spatially and temporally varying radiation patterns from a UV-lamp array, the simulated reactor performance is experimentally validated and extended to explore the impact of geometry variations. Mass-transfer limitations between the corrugated surface and the reservoir bulk are identified as a determining factor in the degradation rate of MB. Optimization studies suggest minimizing the corrugation half-angle to improve reactor performance for a given area, increasing the number of corrugations rather than the corrugation depth subject to practical limitations arising from undesirable bubble formation at small aperture widths. Given the relevance of mass transfer to this system, future work is needed to elucidate the experimental impact of reservoir volume and geometry while validating the use of flat-plate correlations for mass transfer. (C) 2012 American Institute of Chemical Engineers AIChE J, 59: 560-570, 2013