NOx storage and reduction (NSR) is a periodic catalytic process for converting NO and NO2 (NOx) to N2 in the exhaust of lean burn and diesel engines. The NOx removal process involves two stages on a bifunctional supported catalyst. The first stage involves storage of NOx on an alkali earth component (such as Ba, K) mediated by a precious metal (Pt, Rh). The second stage involves purging by a shorter exposure of rich pulse when an unacceptable amount of NOx is released. The rich pulse is created through intermittent rich operation of the engine, producing a mixture of H2, CO, and low molecular weight hydrocarbons. The objective of this experimental study is to elucidate the steady-state and dynamic features of NSR on model Pt/Ba/Al2O3 monolithic catalysts in terms of NOx conversion, selectivity, and productivity. To meet this objectives a bench-scale monolith reactor is used to evaluate NOx storage and reduction, using H2 and CO as reductants in the temperature range of 25-550oC. In-depth steady-state and cycling experiments are carried out to evaluate the light-off and NOx conversion and product distribution as a function of the reductant, storage and regeneration timing, feed temperature and composition. The effectiveness of H2 and CO reductants are evaluated under steady state and cycling conditions. We compare the efficiency of the different reductants to achieve a prescribed NOx conversion. Particular attention is focused on the production of ammonia, a problematic byproduct during NSR. Pre-aged Pt/BaO/Al2O3 catalyst is compared to a BaO/Al2O3 and Pt/Al2O3 catalysts to elucidate the roles of the precious metal and storage functions. Steady state experiments are carried out for several of the underlying chemistries to shed light on the product distributions as a function of operating conditions. The steady state reaction between NO and H2 produces a complex mixture of N2O, NH3, and N2 which is a function of the catalyst temperature and feed concentration. NOx conversion is complete at temperatures exceeding 100 oC for both lean and rich feeds. Under lean conditions the NOx conversion exhibits a sharp maximum after H2 oxidation ignition. NH3 is an important product in O2 deficient conditions, while N2 and N2O are the main products at higher O2 concentrations. NH3 oxidation lights off at 150 oC, producing a mixture of N2, NO, and N2O, which is important since the beginning of the lean wave during cycling, contacts the end of the rich phase, where NH3 is the main nitrogen containing species. Multiple steady states are observed when the feed O2 concentration exceeds a critical value. The NOx conversion achieves a maximum value within the region of multiplicity. H2, CO and H2/CO mixtures are compared in terms of multiplicity features and the NOx conversion. These data are used to help interpret the cycling experiments. Cycling experiments show a maximum in reductant efficiency in the H2 experiments occurs when the stoichiometric number during the rich cycle is equal to 0.95. The maximum NOx conversion and N2 selectivity approach 90% and 85%, respectively, which is achieved in a temperature window of 300oC to 360oC on the aged Pt/BaO catalyst. NH3 is formed during the latter part of the rich cycle once the oxygen is depleted, while N2O is produced at the onset of the rich pulse. The time-averaged NH3 production decreases with increasing average monolith temperature. The experiments run also reveal the effects of the pulse composition and timing on NH3 production. Finally, the existence of multiple cyclic states is explored for different operating conditions.