Details

Autor(en) / Beteiligte

• Kondratev, Stanislav O.
• Zaitsau, Dzmitry H.
• Vostrikov, Sergey V.
• Li, Shao
• Bösmann, Andreas
• Wasserscheid, Peter
• Müller, Karsten
• Verevkin, Sergey P.

Titel

Thermochemical properties of 6,7-benzindole and its perhydrogenated derivative: A model component for liquid organic hydrogen carriers

Ist Teil von

• Fuel (Guildford), 2022-09, Vol.324, p.124410, Article 124410

Ort / Verlag

Elsevier Ltd

Erscheinungsjahr

2022

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• [Display omitted] •6,7-benzindole has been evaluated thermodynamically as a LOHC model component.•Caloric data for the 6,7-benzindole and dodeca 6,7-benzindole are provided.•A lower heat of reaction than for homocyclic LOHCs is observed for dehydrogenation.•Efficient and dense storage of hydrogen can be realized using 6,7-benzindole. Liquid Organic Hydrogen Carriers are substances that store hydrogen by reversible hydrogenation of aromatic compounds. A major advantage is the fact that they enable the safe and dense storage of large amounts of hydrogen. Nitrogen-containing heterocycles, particularly with five-membered rings, have demonstrated the advantage of lower heats of reaction for dehydrogenation compared to homocyclic systems. In this work, 6,7-benzindole and its hydrogenated form, dodecahydro-6,7–benzindole, have been analyzed regarding their thermodynamic properties. The results have been obtained via high-precision combustion calorimetry and accompanied by quantum-chemical calculations to validate the results. The enthalpy of reaction for dehydrogenation has been determined as ΔrHmo(gas) = +348.9 ± 3.5 kJ·mol−1 in the gas phase and ΔrHmo(liq) = +325.7 ± 3.7 kJ·mol−1 in the liquid phase (ΔrHmo(gas) = +58.2 ± 0.6 kJ·molH2–1 and ΔrHmo(liq) = +54.3 ± 0.6 kJ·molH2–1, respectively). This reaction enthalpy is similar to values for other heterocyclic systems like indole and about 11 kJ·molH2–1 lower than that of homocyclic systems, such as perhydro dibenzyl toluene. As a consequence, it can be expected that the temperature needed thermodynamically to enable hydrogen release from dodecahydro-6,7–benzindole will be lower than for the dehydrogenation of perhydro dibenzyl toluene.