Experimental
Catalytic activity experiments were conducted using 70–100 mesh powdered catalysts in 4-mm-diameter packed
beds, typically 5- to 10-mm in height, housed in an isothermal tube furnace. Reactant gases were supplied with
electronic mass flow controllers. The product stream passes through multiple ice bath condensers and then to an online gas chromatograph (GC) that monitors carbon dioxide, carbon monoxide, hydrogen, methane, and nitrogen (sometimes used as a diluent). Thermocouples positioned above and/or below the catalytic bed allow for
temperature monitoring. Residence times down to about 5-ms are achievable in these systems. All experiments
were conducted at atmospheric pressure. For each experiment, catalysts are reduced in 10- to 20-vol% hydrogen in nitrogen for 1 to 2 hours, depending on the composition. After reducing, the catalyst is heated to reaction temperatures under nitrogen flow followed by introduction of reactant gases. At each temperature, the product stream composition is allowed to reach a steady state value before continuing on to a different temperature. In this way, activity graphs showing conversion and product selectivites are generated as a function of temperature and/or residence time.
Experimental
Catalytic activity experiments were conducted using 70–100 mesh powdered catalysts in 4-mm-diameter packed
beds, typically 5- to 10-mm in height, housed in an isothermal tube furnace. Reactant gases were supplied with
electronic mass flow controllers. The product stream passes through multiple ice bath condensers and then to an online gas chromatograph (GC) that monitors carbon dioxide, carbon monoxide, hydrogen, methane, and nitrogen (sometimes used as a diluent). Thermocouples positioned above and/or below the catalytic bed allow for
temperature monitoring. Residence times down to about 5-ms are achievable in these systems. All experiments
were conducted at atmospheric pressure. For each experiment, catalysts are reduced in 10- to 20-vol% hydrogen in nitrogen for 1 to 2 hours, depending on the composition. After reducing, the catalyst is heated to reaction temperatures under nitrogen flow followed by introduction of reactant gases. At each temperature, the product stream composition is allowed to reach a steady state value before continuing on to a different temperature. In this way, activity graphs showing conversion and product selectivites are generated as a function of temperature and/or residence time.
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