摘要:
A fuel cell includes an anode, a cathode, and an ion conducting membrane interposed between the anode and cathode. The ion conducting membrane includes a base layer that has an ion conducting polymer and additive layer that has a metal supported on an oxide support, the oxide support scavenging hydroxyl radicals formed during fuel cell operation.
摘要:
A unitized electrode assembly for a fuel cell comprising an electrolyte membrane, a subgasket, and a sealing bead disposed therebetween is disclosed. The sealing bead adapted to fill a tenting region formed between the membrane and the subgasket to maximize an operating life of the electrolyte membrane by militating against wear of membrane expansion during use of the fuel cell.
摘要:
A stand-alone fuel processor (10) for producing hydrogen from a hydrocarbon fuel for a fuel cell engine in a vehicle. The fuel processor (10) includes a primary reactor (14) that dissociates hydrogen and other by-products from the hydrocarbon fuel as a reformate gas. The reformate gas is applied to a WGS reactor (48) to convert carbon monoxide and water to hydrogen and carbon dioxide. The WGS reactor (14) may include an adsorbent for adsorbing carbon monoxide. The reformate gas from the WGS reactor (48) is then sent to a rapid-cycle PSA device (12) for adsorbing the undesirable by-products in the gas and generates a stream of pure hydrogen. A liquid water separator (70) separates water from the reformate gas before it is applied to the PSA device (12). The PSA device (12) uses a portion of the separated hydrogen as a desorbing gas to purify the adsorbent in the PSA device (12). The by-products of the reformate gas can be used as a fuel in a combustor (30) that generates heat for the primary reactor (14).
摘要:
Carbon dioxide is removed from gas streams comprised predominantly of gases that are less strongly adsorbed than is carbon dioxide by passing the gas stream through a bed of type X zeolite having a silicon to aluminum atomic ratio not greater than about 1.15 and at least 75% of the exchangeable cations of which are potassium ions, thereby adsorbing the carbon dioxide from the gas stream. The process is particularly advantageous when applied to the removal of low levels of carbon dioxide from gas streams at temperatures of about 0 to 80° C.
摘要:
A unitized electrode assembly for a fuel cell comprising an electrolyte membrane, a subgasket, and a sealing bead disposed therebetween is disclosed. The sealing bead adapted to fill a tenting region formed between the membrane and the subgasket to maximize an operating life of the electrolyte membrane by militating against wear of membrane expansion during use of the fuel cell.
摘要:
A fuel processor system contains an autothermal reactor (ATR) that produces a hydrogen-rich first gas stream containing carbon monoxide. Downstream of the ATR, a pressure swing adsorber produces a second hydrogen-rich gas stream containing 5 ppm carbon monoxide or more. Downstream of the PSA, there is a methanation reactor sized to reduce the CO level of the second stream below 5 ppm. A method of operating of proton exchange membrane fuel cell stack involves cooling the methanator output and feeding it into the stack as an anode fuel.
摘要:
A PSA unit for purifying hydrogen in a fuel processor system. The PSA unit employs rotary valves that cycle the pressurization of vessels, including an adsorbent, between a high pressure state and a low pressure state. The purified hydrogen is released from the vessels through a purified gas output port when the vessels are in the high pressure state and the impurities are released through an exhaust port when the vessels are in the low pressure state. The PSA unit also employs a mass flow control device and a pressure sensor in the purified gas output port. A controller receives a pressure signal from the pressure sensor, and controls the flow through the mass flow control device and the speed of the rotary valves so that the proper pressure is maintained at the hydrogen output port.
摘要:
An apparatus removes CO from a hydrogen-rich gas stream in a hydrogen fuel cell system. CO fouls costly catalytic particles in the membrane electrode assemblies. Both a catalyst adapted to perform a water gas shift reaction, and a carbon dioxide adsorbent are disposed in a rotating pressure swing adsorber housing. The adsorption of carbon dioxide shifts equilibrium toward carbon monoxide consumption. A second adsorbent may be disposed in the housing for adsorbing carbon monoxide at low temperatures, and is adapted to desorb carbon monoxide at high temperatures. The present invention advantageously eliminates a unit operation from a space-constrained fuel cell vehicle by combining the WGS catalyst and a CO2 adsorbent in a single reactor/housing. The apparatus further eliminates the use of a PROX reactor, by providing an apparatus which incorporates CO2 adsorption and consequent carbon monoxide consumption in the place of the PROX reactor.
摘要:
A method for removing sulfur-containing species from a liquid hydrocarbon fuel and capturing a portion of vaporized sulfur-free fuel to be processed into hydrogen for use in a fuel cell engine. Sulfur is removed by heating the fuel under pressure to keep the fuel in the liquid phase, and passing it over a sulfur trap that contains an adsorbent bed that adsorbs the sulfur-containing species in the fuel. The sulfur-free fuel is depressurized to a two-phase hydrocarbon mixture. The vapor/liquid mixture is separated, and the liquid portion is sent to a fuel processor system. The vapor portion is sent to a vapor canister where it is adsorbed on an activated carbon adsorbent. The adsorbed hydrocarbon vapors are desorbed from the vapor trap by purging it with air when the fuel cell engine is first started up.
摘要:
Substantially all of the carbon dioxide is removed from a gas containing up to about 1% by volume carbon dioxide by subjecting the gas to a pressure swing adsorption process using a two layer adsorption system, wherein the first layer contains activated alumina and the second layer is a zeolite or a combination of zeolites having a silicon to aluminum atomic ratio of at least 1.5. The process is particularly suitable for removing substantially all carbon dioxide and water vapor contained in air prior to subjecting the air to cryogenic distillation.