Issue 5, 2022

Sequential separation-driven solar methane reforming for H2 derivation under mild conditions

Abstract

Steam methane reforming (SMR) is by far the dominant approach of hydrogen production, but its feasibility for producing low-carbon-footprint H2 has been constrained by high reaction temperatures (>800 °C), complexity of processes, and high energy penalties associated with H2 and CO2 separation. To address such key challenges, we propose a new principle of multi-product sequential separation and a new method of sequential separation-driven SMR for the first time. Target product species H2 and CO2 are sequentially separated, so that their partial pressures are maintained close to their maxima at thermodynamic equilibrium to effectively drive methane conversion to full completion theoretically. The new principle enables a remarkable decrease in the SMR temperature and a dramatic reduction in energy penalties of separation in theory and practice. The effectiveness of the new principle and method is demonstrated by a proof-of-concept reactor with a Pd–Ag membrane and alternating nickel catalyst/hydrotalcite sorbent combinations. High-purity H2 and CO2 are directly obtained with >99% conversion of methane and >99% yield and selectivity of H2 and CO2 under mild conditions of 400 °C and 1 bar. Fast and stable production of H2 and CO2 is demonstrated over 6000 cycles. The highly compact reactor and mild operating conditions further enable integration with a parabolic trough solar collector, by which mid-temperature solar thermochemical H2 production and CO2 capture are achieved. The solar-to-H2 efficiency is 3.4% with direct solar illumination. The efficiency can be enhanced to 46.5% or above with solar thermal energy storage and advances in mid-/low-temperature SMR catalysts and CO2 sorbents, and can be further enhanced to beyond 60% with low-energy-penalty separation technologies.

Graphical abstract: Sequential separation-driven solar methane reforming for H2 derivation under mild conditions

Supplementary files

Article information

Article type
Communication
Submitted
15 Dec 2021
Accepted
07 Mar 2022
First published
07 Mar 2022

Energy Environ. Sci., 2022,15, 1861-1871

Sequential separation-driven solar methane reforming for H2 derivation under mild conditions

Y. Ling, H. Wang, M. Liu, B. Wang, S. Li, X. Zhu, Y. Shi, H. Xia, K. Guo, Y. Hao and H. Jin, Energy Environ. Sci., 2022, 15, 1861 DOI: 10.1039/D1EE03870B

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements