(13) PFSA membranes do not function over 100 ☌ because they need condensed water within the membrane to mediate proton conduction.

Palladium membranes require temperatures over 350 ☌ for hydrogen separation, and they cannot be used for compression.ĮHPs were originally developed by General Electric (14) with the emergence of perfluorosulfonic acid (PFSA) membranes, such as Nafion, and have been used for hydrogen compression and reuse in various industrial settings. Adsorption processes do not operate continuously because they saturate and require regeneration. (12) Electrochemical hydrogen pumps (EHPs) (13) featuring proton-selective polymer electrolyte membranes (PEMs) represent an alternative separation platform that can simultaneously separate and compress hydrogen continuously. The hydrogen used in these processes often requires separation from syngas.Ĭonventional hydrogen separations encompass several different methods (8) such as cryogenic cooling, (9) thermal metal hydride adsorption, (10) pressure swing adsorption, (11) and palladium membranes. It is important to note that numerous chemical processes (7) use hydrogen from SMR, e.g., ammonia production for fertilizers by the Haber–Bosch process, desulfurization in petrochemical processes, metal refining, chemical hydrogenation, and semiconductor manufacturing. (6) The SMR process uses natural gas as a feedstock and generates syngas, a mixture that primarily consists of hydrogen, carbon monoxide (CO), and some carbon dioxide (CO 2). Over 90% of hydrogen used in the United States is derived from steam methane reforming (SMR). As renewables displace natural gas as an energy source, there is still significant value in harnessing natural gas as a source of carbon and hydrogen for chemical manufacturing (e.g., surfactants and plastics) and the production of fuels. Meeting the ambitious goal of a 50% reduction in GHG emissions by 2030, as outlined by the Biden Administration, (3) or the 2016 Paris Agreement (4) to limit global temperature increases below 2 ☌ requires the continued adoption of renewable energy sources, such as solar, nuclear, and wind the proliferation of energy storage technologies, such as batteries and the implementation of blue, green, and pink hydrogen as energy vectors and chemical feedstocks in the global economy. (2) However, natural gas combustion still yields CO 2, a greenhouse gas (GHG) and a large contributor to climate disruption. (1) The 32% reduction in CO 2 emissions from the electric power sector in the United States since 2005 is largely attributed to natural gas supplanting coal for burning in thermal electric plants, as it is cheaper and a cleaner fuel. Natural gas prices over the past 15 years have experienced a precipitous drop due to innovations made in fracking technology and the extraction of this resource from shale layers.

Finally, the EHP with the said materials displayed a small performance loss of 12 μV h –1 for purifying hydrogen from syngas for 100 h at 200 ☌. The ability to operate the EHP at an elevated temperature allowed the EHP to purify hydrogen from gas feeds with large CO contents at 1 A cm –2. The ion-pair HT-PEM and phosphonic acid ionomer binder enabled the EHP to be operated in the temperature range from 160 to 220 ☌. In this work, a high-temperature PEM (HT-PEM) EHP purified hydrogen to 99.3%, with greater than 85% hydrogen recovery for feed mixtures containing 25–40% CO. Electrochemical hydrogen pumps (EHPs) featuring proton-selective polymer electrolyte membranes (PEMs) represent an alternative separation platform with fewer unit operations because they can simultaneously separate and compress hydrogen continuously.

The purified hydrogen is then fed to a compressor to deliver hydrogen at high pressures. Conventional hydrogen separations from reformed hydrocarbons often deploy a water gas shift (WGS) reactor to convert CO to CO 2, followed by adsorption processes to achieve pure hydrogen.

Pem ram pressure 100