Main group catalysis for H ₂ purification based on liquid organic hydrogen carriers

Abstract

Molecular hydrogen (H 2 ) is one of the most important energy carriers. In the midterm future, a huge amount of H 2 will be produced from a variety of hydrocarbon sources through conversion and removal of contaminants such as CO and CO 2 . However, bypassing these purification processes is desirable, given their energy consumption and environmental impact, which ultimately increases the cost of H 2 . Here, we demonstrate a strategy to separate H 2 from a gaseous mixture of H 2 /CO/CO 2 /CH 4 that can include an excess of CO and CO 2 relative to H 2 and simultaneously store it in N-heterocyclic compounds that act as liquid organic hydrogen carriers (LOHCs), which can be applied to produce H 2 by subsequent dehydrogenation. Our results demonstrate that LOHCs can potentially be used for H 2 purification from CO- and CO 2 -rich crude H 2 in addition to their well-established use in H 2 storage.

Remote Back Strain: A Strategy for Modulating the Reactivity of Triarylboranes

“…Finally, we applied B 2 to the catalytic hydrogenation of Qin using a gaseous mixture of H2/CO/CO2 (1/1/1 molar ratio), a model of the crude H2 that is produced from a variety of carbonbased resources such as natural gas and biomass (Scheme 3B). 8,21 H4-Qin was obtained in >99% yield, demonstrating that Qin can be potentially used as an organic material that simultaneously separates and stores H2 directly from crude gaseous H2. This study proposes a strategy of modulating the 'remote' back strain of triarylboranes to finely tune their Lewis acidity by varying the size and shape of their aryl meta-substituents.…”

“…We have recently investigated the hydrogenation of 2methylquinoline using a gaseous mixture of H2/CO/CO2 and Mahiro Sakuraba a Taichi Morishita a Taiki Hashimoto a Sensuke Ogoshi* a Yoichi Hoshimoto* a,b Synlett Letter / Cluster / New Tools Template for SYNLETT Thieme demonstrated that the catalyst turnover number (TON) increases significantly when the meta-substituent R in B(2,6-Cl2-C6H3)(2,6-F2-3,5-R2-C6H)2 was changed from F (TON 1000) to Cl (TON 1400) and finally to Br (TON 1520). 8 Given their nearly identical energy levels of the p orbitals on each boron center, we speculated that the size and shape of the meta-substituents (R in Figure 2) could have a substantial impact on the Lewis acidity and reactivity of BAr3 (or BAr2Ar′) via control of the 'remote' back strain. Herein, we report the synthesis of novel homoleptic boranes B(2,6-F2-3,5-R2-C6H)3 (B 1 : R = trimethylsilyl, TMS; B 2 : R = allyl) to evaluate the impact of the remote back strain on the global and effective Lewis acidity by comparison with B 3 (R = H) (Figure 2).…”

Recent Advances in Catalysis Using Organoborane-Mediated Hydride Abstraction

“…Ogoshi, Hoshimoto and coworkers reported organoboranecatalyzed dehydrogenation applied to the purification of molecular hydrogen (Scheme 15). 30 Scheme 15 Borane-mediated hydride abstraction for the interconversion of liquid organic hydrogen carriers.…”

Assembly Engineering of Rh Atoms on CoAl-Layered Double Hydroxide Nanosheets for Boosting Alkaline Water Splitting

“…1,2 Hydrogen, as a clean and renewable energy, is considered as a promising candidate for fossil fuels, thanks to its high energy density and zero CO 2 emissions. 3,4 Until now, there are various methods to produce hydrogen energy, including natural gas reformation, 5 coal gasification, 6 and water splitting. 7 Among these, water splitting using electrochemical technology is regarded as the greenest, most simple, and efficient approach to generate hydrogen.…”

“…The increasing consumption of fossil fuels and deterioration of environment have compelled researchers to explore sustainable, green, and environmentally friendly energy sources to replace fossil fuels. , Hydrogen, as a clean and renewable energy, is considered as a promising candidate for fossil fuels, thanks to its high energy density and zero CO 2 emissions. , Until now, there are various methods to produce hydrogen energy, including natural gas reformation, coal gasification, and water splitting . Among these, water splitting using electrochemical technology is regarded as the greenest, most simple, and efficient approach to generate hydrogen. − Nowadays, Pt/C is regarded as a benchmark catalyst for hydrogen evolution reaction (HER), while IrO x /RuO x are the benchmarks of oxygen evolution reaction (OER).…”