Solid Electrolyte Membrane Reactors

Abstract

IntroductionThe present chapter introduces a specifi c type of membrane reactor only briefl y mentioned in Chapter 1 . The solid electrolyte membrane reactor s ( SEMR ) -or electrochemical membrane reactors as they also are called -are equipped with ion -conducting membranes, which ideally are impermeable for non -charged reaction species. These reactors operate as electrochemical cells, in which the oxidation and reduction reactions are carried out separately on catalyst/electrodes layers located on the opposite sides of the electrolyte. The development of solid electrolyte membrane reactors has reached a semi -commercial stage in fuel cells, in which the maximal generation of electric energy by the total oxidation of hydrogen or hydrocarbon feeds is the primary goal of operation. Research on chemical reactor applications is strongly concentrated in the high -temperature range using either oxygen ion -or proton -conducting inorganic membranes. Some interesting examples were published recently, investigating proton -conducting polymeric membranes for the production of chemicals.This chapter gives a brief overview on the current status and future trends in the development and application of solid electrolyte reactors equipped with solid electrolyte ( SE ) materials used as membranes in these reactors. Initially the working principle of a solid electrolyte membrane reactor and material aspects are discussed. The second part of the chapter gives a detailed description of the special aspects concerning the modeling of solid electrolyte membrane reactors, as well as the application examples of maleic anhydride ( MA ) synthesis and oxidative dehydrogenation of ethane. Finally the chapter reviews recent papers concerning solid electrolyte membrane reactors applying:• high -temperature oxygen ion conductors, • high -temperature proton conductors, • low -temperature proton conductors.There are some recent review papers, especially written for high -temperature applications, which we would like to recommend to readers interested in more

Direct Conversion of Methane to C2Hydrocarbons in Solid-State Membrane Reactors at High Temperatures

“…The electrodes must be porous for the diffusion of the gas-phase reagents/products but also to have a connected structure for electrical conduction, while the electrolyte must be structurally dense and thin, allowing only ionic conduction. 105,118,145,150 The most used materials for an oxygen ion conductor (electrolyte) are yttria-stabilized zirconia (YSZ), followed by scandia-stabilized zirconia (ScSZ), gadolinium (or samarium)doped ceria (GDC or SDC), and perovskite materials such as lanthanum gallate doped with Sr/Mg (LSGM). These solid electrolytes are normally operated at high temperature, and their total conductivities are strongly dependent on the thermal conditions.…”

Assessment of the electrical properties and chemical stabilities of BaCe 0 . 9 Y 0 . 1 O 3 −δ and BaCe Graça1, Loureiro2, Holz3 et al. 2022Intl J of Energy Research4000View full textAdd to dashboardCite

“…In this respect, ECMRs are rapidly becoming an attractive alternative, compared to conventional separation processes, in various chemical applications, with the additional ability to induce electrochemical enhancements. [5][6][7][8][9][10][11][12][13][14][15] Proton ceramic materials are viable solutions to operate in ECMRs at low temperatures, due to their lower activation energy for ionic diffusion (E a = 0.3-0.6 eV), with respect to that of oxygen-ion conductors. 16,17 Of the potential ceramic proton conductors, materials with an ABO 3 perovskite structure have been shown to be the most viable compositions.…”

Electrochemical Membrane Reactor Modeling for Lignin Depolymerization

“…The electrochemical membrane reactor (EMR) is an attractive concept that can guide many sustainable processes to commercial applications. The most popular example is the membrane cell for chlor-alkali electrolysis process to produce sodium hydroxide, chlorine, and hydrogen from brine. , Another emerging application is the treatment of metal-contaminated wastewater through an EMR. , The wastewater from pulp and paper industry, which contains lignin, suspended and dissolved solids can be treated electrochemically via complete oxidation of the organics to CO 2 and water. Utilizing Ti/RuO 2 as an anode, the organic matter was reduced from 120 000 mg L –1 to 90 mg L –1 which matches the wastewater effluent requirements .…”