Simultaneous Production of Hydrogen and Synthesis Gas by Combining Water Splitting with Partial Oxidation of Methane in a Hollow‐Fiber Membrane Reactor

Abstract

Hydrogen is gaining more and more attention because it is regarded as an important future fuel. Today, hydrogen is mainly produced from nonrenewable natural gas and petroleum. With concerns over worldwide energy demands and global climate change, alternative sources must be found. Obviously, water is recommended as the ideal source for the generation of large amounts of hydrogen.[1] In addition to electrolysis, recently several new processes, such as photovoltaic-photoelectrochemical water splitting [2][3][4] and one-step or multistep thermochemical water splitting [5,6] based on focused solar [7][8][9] or nuclear [10] heat, have been developed. Although water dissociation into oxygen and hydrogen is conceptually simple [Eq. (1)], efficient hydrogen productionfrom water remains difficult as a result of the low equilibrium constant of K p % 2 10 À8 at the relatively high temperature of 950 8C.

Nitrogen Production by Efficiently Removing Oxygen From Air Using a Perovskite Hollow-Fiber Membrane With Porous Catalytic Layer

“…When temperature reached 900°C, nitrogen purity of 98.9% and methane conversion of 78% was obtained. Based on Wagner equation (Jiang et al, 2008; Chen et al, 2014), oxygen permeation rate is promoted by increasing operation temperature. Thus, more oxygen ( J O 2 increased from 2.6 to 4.8 cm 3 min −1 cm −2 , as shown in Figure 5B) was removed from core side to shell side and consumed by methane oxidation there.…”

A review on solar thermal syngas production via redox pair-based water/carbon dioxide splitting thermochemical cycles

“…This idea was proposed almost simultaneously and independently by a Greek research group employing ironate compositions of the type La 1 À x Sr x M y Fe 1 À y O 3 À δ (M ¼Ni, Co, Cu, Cr [155,156]) and a German group employing compositions of the type Ba 1 À x Sr x Co y Fe 1 À y O 3 À δ (BSCF/BSFZ, respectively) [157,158]. This concept is based again on continuously extracting oxygen from the reaction products at high temperatures by MIEC membranes with high oxygen permeability -such as dense perovskite membranes -that can act as oxygen transfer materials when a difference in oxygen concentration is established along their sides.…”

Hydrogen production via thermochemical water splitting

“…Interestingly, although perovskites are also nonstoichiometric compounds and can operate in a reaction pair scheme similar to that of Eqns (11.1) and (11.2) above, they were not employed at first in such a thermal reductionewater-splitting scheme. Instead, a chemical reduction was employed in combination with a mixed oxygen-ion and electron-conducting (MIEC) membrane reactor concept proposed almost simultaneously and independently by one Greek group and one German research group (Jiang, Wang, Werth, Schiestel, & Caro, 2008). This concept is based on continuously extracting oxygen from the reaction products and thus shifting the equilibrium of the TR reaction.…”

“…The high Figure 11.5 Schematics of the membrane reactor operating principle for simultaneous production of hydrogen and syngas. Adapted from Jiang et al (2008).…”