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Autothermal reforming of methane was investigated in a Reverse Flow Reactor with commercial Rh/Al 2 O 3 catalyst in pellets. The process was carried out in a catalytic fixed bed reactor and switching of feed flow direction was obtained through four electrovalves synchronized in pair. Temperature profile of the catalyst bed was measured by fast IR thermography and product composition was measured with a continuous gas analyzer. Reactor performance and catalyst temperature profile are presented as a function of feed direction switching period, water to methane inlet ratio and total inlet flow rate. Results are compared to steady state operation.

This work presents a simulative energy efficiency analysis performed on fuel processor – PEMFC systems, considering methane as fuel and steam reforming or autothermal reforming as processes to produce hydrogen. Computation of energy efficiency takes into account the power required by the auxiliary units, coupling of the fuel processor with the fuel cell as well as heat recovery and integration. Two system configurations were simulated and compared: an innovative configuration, based on an integrated membrane reactor directly coupled with the fuel cell, and a conventional configuration, based on a classic reforming reactor followed by a conventional CO clean-up section, constituted by water gas shift and preferential CO oxidation reactors. Reforming temperature, plant pressure, steam to methane and oxygen to methane inlet ratios were considered as process parameters. The effect of the addition of steam as sweep gas is also presented and discussed.

In this work we report a simulative energy efficiency analysis performed on innovative fuel processor – PEM fuel cell systems in which hydrogen is produced via methane autothermal reforming, separated with a membrane unit coupled with a water gas shift reactor and then converted into electric energy by means of the PEM fuel cell. Two basic configurations are investigated: one with the membrane unit placed downstream the water gas shift reactor and the other with the membrane unit embedded into the water gas shift reactor. The results are discussed and compared with the case of a fuel processor constituted by an autothermal reforming reactor followed by two water gas shift reactors and a preferential CO-oxidation reactor. Pressure, steam to methane and oxygen to methane inlet ratios are explored as operation variables. The effect of addition of steam as sweep gas into the permeate side of the membrane is also presented and discussed.

Catalytic autothermal reforming of methane was studied over a commercial rhodium catalyst as a function of feed flow rate, feed composition and oven temperature. The process is carried out in a catalytic fixed bed reactor inserted in a tubular oven. Temperature profile of the catalyst bed was measured by IR thermography and product composition was measured with a continuous gas analyzer. The effect of water addition at fixed flow rate on catalyst temperature profile was investigated in two ways. In one case, upon water addition, an equivalent amount of nitrogen was removed from the feed in order to keep oxygen and methane concentrations constant. With this protocol nitrogen to oxygen ratio varies as a function of amount of water in the feed. In the other case, upon water addition, nitrogen, oxygen and methane were all reduced to keep total flow rate constant, thus keeping both oxygen to methane and nitrogen to oxygen ratios constant. The effect of water addition on product composition was investigated as a function of reactor thermal level, regulated by acting on oven temperature.

Catalytic autothermal reforming of methane was studied over a commercial nickel catalyst as a function of feed flow rate, feed composition and oven temperature. Temperature profile of the catalyst bed was measured by IR thermography and product composition was measured with a continuous gas analyzer. The effect of water addition on product composition and catalyst temperature profile was investigated in two different ways: by keeping oven temperature constant and by adjusting oven temperature in order to achieve the same maximum temperature in the catalyst bed. Temperature distribution in the catalyst was measured and, for each operating condition, the fraction of catalyst above a limiting value for deactivation and below a limiting value for coke formation was quantified. These information were coupled with data of methane conversion and hydrogen production, to identify a region of favourable reactor operating conditions, in the plane AIR/CH4–H2O/CH4.