A Computational Study on the Decomposition of Formic Acid Catalyzed by (H2O)x, x = 0−3: Comparison of the Gas-Phase and Aqueous-Phase Results

Chen, Hsin‐Tsung; Chang, Jee-Gong; Chen, Hui-Lung

doi:10.1021/jp801247d

Cited by 36 publications

(25 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Keywords: biomass • formic acid • high temperature and pressure water • reactor wall • reduction the dehydration reactions. The literature provides many studies on this topic, [20][21][22][23][24][25] taking into account the possible effects of density, surface-catalyzed reactions, and ionic or radical mechanisms. However, although all of the experimental results have confirmed that the decarboxylation is the main reaction path under supercritical or near-supercritical conditions, several inconsistencies regarding the mechanism of formic acid decomposition in the presence of water have not been fully resolved.…”

Section: Introductionmentioning

confidence: 99%

The Role of the Reactor Wall in Hydrothermal Biomass Conversions

Fábos

Yuen

Masters

et al. 2012

Chemistry An Asian Journal

View full text Add to dashboard Cite

The processing of renewable feedstocks to platform chemicals and, to a lesser degree, fuels is a key part of sustainable development. In particular, the combination of lignocellulosic biomass with hydrothermal upgrading (HTU), using high temperature and pressure water (HTPW), is experiencing a renaissance. One of the many steps in this complicated process is the in-situ hydrogenation of intermediate compounds. As formic acid and related low-molecular-weight oxygenates are among the species generated, it is conceivable that they act as a hydrogen source. Such hydrogenations have been suggested to be catalyzed by water, by bases like NaOH, and/or to involve "reactive/nascent hydrogen". To achieve the temperatures and pressures required for HTU, it is necessary to conduct the reactions in high-pressure vessels. Metals are typical components of their walls and/or internal fittings. Here, using cyclohexanone as a model compound for more complex biomass-derived molecules, iron in the wall of high-pressure stainless steel reactors is shown to be responsible for the hydrogenation of ketones with low-molecular-weight oxygenates acting as a hydrogen source in combination with water.

show abstract

Section: Introductionmentioning

confidence: 99%

The Role of the Reactor Wall in Hydrothermal Biomass Conversions

Fábos

Yuen

Masters

et al. 2012

Chemistry An Asian Journal

View full text Add to dashboard Cite

show abstract

“…The role of hydrogen bonded molecular complexes on the kinetics and dynamics of gas-phase free radical reactions has been the focus of interest of both experimental and theoretical investigations, [1][2][3][4][5][6], and several articles have been published involving possible one-molecule catalysis in reactions of OH radicals with organic volatile compounds [7][8][9].…”

Section: Introductionmentioning

confidence: 99%

Single water-molecule catalysis in the glyoxal + OH reaction under tropospheric conditions: Fact or fiction? A quantum chemistry and pseudo-second order computational kinetic study

Iuga

Álvarez-Idaboy

Vivier–Bunge

2010

Chemical Physics Letters

View full text Add to dashboard Cite

“…64 (formamide and HCN formation) and in ref. 65 (HCOOH formation). The transition states and barrier heights in the latter works are quite similar to our results at T = 650 K, considering the different treatment of temperature (approximations based on harmonic vibrations in the literature versus moleculardynamics in our case) and the different quantum-mechanical approximations [B3LYP, G2M, MP2, and CCSD(T) in the literature versus density functional theory-Perdew-Burke-Ernzerhof (DFT-PBE) in our case].…”

Section: Resultsmentioning

confidence: 99%

Formation of nucleobases in a Miller–Urey reducing atmosphere

Ferus

Pietrucci

Saitta

et al. 2017

Proc. Natl. Acad. Sci. U.S.A.

128

126

View full text Add to dashboard Cite

The Miller-Urey experiments pioneered modern research on the molecular origins of life, but their actual relevance in this field was later questioned because the gas mixture used in their research is considered too reducing with respect to the most accepted hypotheses for the conditions on primordial Earth. In particular, the production of only amino acids has been taken as evidence of the limited relevance of the results. Here, we report an experimental work, combined with state-of-the-art computational methods, in which both electric discharge and laser-driven plasma impact simulations were carried out in a reducing atmosphere containing NH 3 + CO. We show that RNA nucleobases are synthesized in these experiments, strongly supporting the possibility of the emergence of biologically relevant molecules in a reducing atmosphere. The reconstructed synthetic pathways indicate that small radicals and formamide play a crucial role, in agreement with a number of recent experimental and theoretical results. The following explorations showed that a broad array of amino acids could be synthesized, but there was no evidence that all of the fundamental molecules of the RNA genetic code could be produced alongside others in this type of experiment (2-5). Additionally, the significant persistence of reducing atmospheres in a geological timescale has been seriously debated (6). Finally, many scientists have claimed that this experiment is not related to early-Earth conditions and does not provide fundamental building blocks (i.e., nucleobases) important for the evolution of early life possibly based on RNA (7-13). In 2001, Saladino, Di Mauro, and coworkers (14) proposed that the parent molecule for the one-pot synthesis of nucleobases is formamide (15-23). Their team, together with other authors, demonstrated the formation of (not only) fundamental nucleobases for the origin of RNA in experiments involving the heating of formamide in presence of manifold catalysts (17,(24)(25)(26), upon UV irradiation (27), proton (28) and heavy-particle radiation (29), exposition to shock waves (18), etc. Recently, Hörst et al. (30) also referred to a positive result on qualitative detection of RNA nucleobases and manifold amino acids from tholines created in a N 2 , CH 4 , CO mixture. Their experiment simulated the atmosphere of Titan upon electric discharge. Such experimental results as well as theoretical expectations (31) show that reduced, relatively reactive atmospheres are likely to be more efficient for the synthesis of biomolecules (32). However, it should be noted that several papers report also the formation of biomolecules under neutral (N 2 , CO 2 , H 2 O) conditions (33-35). In our study, we found an interconnection between the original ideas of the pioneering Miller-Urey studies devoted to prebiotic synthesis in a reducing atmosphere and recent results identifying the chemistry of formamide as a source for the synthesis of nucleobases. In addition to traditional hydrogen cyanide (HCN)-based or reducing atmosphere-based concept...

show abstract

A Computational Study on the Decomposition of Formic Acid Catalyzed by (H₂O)_x, x = 0−3: Comparison of the Gas-Phase and Aqueous-Phase Results

Cited by 36 publications

References 32 publications

The Role of the Reactor Wall in Hydrothermal Biomass Conversions

The Role of the Reactor Wall in Hydrothermal Biomass Conversions

Single water-molecule catalysis in the glyoxal + OH reaction under tropospheric conditions: Fact or fiction? A quantum chemistry and pseudo-second order computational kinetic study

Formation of nucleobases in a Miller–Urey reducing atmosphere

Contact Info

Product

Resources

About