On the chemical reactions of carbon dioxide isoelectronic molecules CS2 and OCS with 1-butyl-3-methylimidazolium acetate

2013 ◽  
Vol 49 (94) ◽  
pp. 11083 ◽  
Author(s):  
M. Isabel Cabaço ◽  
Marcel Besnard ◽  
Fabián Vaca Chávez ◽  
Noël Pinaud ◽  
Pedro J. Sebastião ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Chemical Reactions ◽  
Isoelectronic Molecules

scholarly journals New means of hydrogen storage – the potentials of methanol as energy storage for excessive windpower in North Germany

2018 ◽  
Vol 70 ◽  
pp. 01004
Author(s):  
Johannes Gulden ◽  
Andreas Sklarow ◽  
Thomas Luschtinetz
Keyword(s):  
Carbon Dioxide ◽  
Energy Storage ◽  
Solar Energy ◽  
Hydrogen Storage ◽  
Chemical Reactions ◽  
Energy Production ◽  
Technological Development ◽  
Mild Conditions ◽  
Production And Consumption ◽  
North Germany

The aim of the presented project is the technological development of hydrogen storage in methanol. This technology enables the carbon dioxide-based chemical storage of renewable energies as well as a decentralized supply of energy and hydrogen. Additional advantages are the very good compatibility with the existing infrastructure for liquid energy storage as well as the temporal decoupling of energy production and consumption. The latter can be managed independently, thus taking into account the fluctuating nature of wind and solar energy. The centrepiece is the use of new catalysts and processes that enable the chemical reactions in the methanol cycle under mild conditions.

Integrating Catalytic Coal Gasifiers With Solid Oxide Fuel Cells

2010 ◽  
Author(s):  
Nicholas Siefert ◽  
Dushyant Shekhawat ◽  
Thomas Kalapos
Keyword(s):  
Carbon Dioxide ◽  
Fuel Cells ◽  
High Temperature ◽  
Solid Oxide Fuel Cells ◽  
Chemical Reactions ◽  
Steam Gasification ◽  
Solid Oxide ◽  
Oxide Fuel ◽  
Entrained Flow ◽  
Coal Gasifier

A review was conducted for coal gasification technologies that integrate with solid oxide fuel cells (SOFC) to achieve system efficiencies near 60% while capturing and sequestering >90% of the carbon dioxide [1–2]. The overall system efficiency can reach 60% when a) the coal gasifier produces a syngas with a methane composition of roughly 25% on a dry volume basis, b) the carbon dioxide is separated from the methane-rich synthesis gas, c) the methane-rich syngas is sent to a SOFC, and d) the off-gases from the SOFC are recycled back to coal gasifier. The thermodynamics of this process will be reviewed and compared to conventional processes in order to highlight where available work (i.e. exergy) is lost in entrained-flow, high-temperature gasification, and where exergy is lost in hydrogen oxidation within the SOFC. The main advantage of steam gasification of coal to methane and carbon dioxide is that the amount of exergy consumed in the gasifier is small compared to conventional, high-temperature, oxygen-blown gasifiers. However, the goal of limiting the amount of exergy destruction in the gasifier has the effect of limiting the rates of chemical reactions. Thus, one of the main advantages of steam gasification leads to one of its main problems: slow reaction kinetics. While conventional entrained-flow, high-temperature gasifiers consume a sizable portion of the available work in the coal oxidation, the consumed exergy speeds up the rates of reactions. And while the rates of steam gasification reactions can be increased through the use of catalysts, only a few catalysts can meet cost requirements because there is often significant deactivation due to chemical reactions between the inorganic species in the coal and the catalyst. Previous research into increasing the kinetics of steam gasification will be reviewed. The goal of this paper is to highlight both the challenges and advantages of integrating catalytic coal gasifiers with SOFCs.

Free-Radical Chemistry in Supercritical Carbon Dioxide

2004 ◽  
Author(s):  
J. M. Tanko
Keyword(s):  
Carbon Dioxide ◽  
Free Radical ◽  
Supercritical Carbon Dioxide ◽  
Green Chemistry ◽  
Chemical Reactions ◽  
Environmentally Benign ◽  
Supercritical State ◽  
Liquid Phases ◽  
Temperature And Pressure ◽  
Supercritical Carbon

During the 1990s, the chemical industry has focused on ways to reduce and prevent pollution caused by chemical synthesis and manufacturing. The goal of this approach is to modify existing reaction conditions and/or to develop new chemistries that do not require the use of toxic reagents or solvents, or that do not produce toxic by-products. The terms “environmentally benign synthesis and processing” and “green chemistry” have been coined to describe this approach where the environmental impact of a process is as important an issue as reaction yield, efficiency, or cost. Most chemical reactions require the use of a solvent that may serve several functions in a reaction: for example, ensuring homogeneity of the reactants, facilitating heat transfer, extraction of a product (or by-product), or product purification via chromatography. However, because the solvent is only indirectly involved in a reaction (i.e., it is not consumed), its disposal becomes an important issue. Thus, one obvious approach to “green chemistry” is to identify alternative solvents that are nontoxic and/or environmentally benign. Supercritical carbon dioxide (sc CO2) has been identified as a solvent that may be a viable alternative to solvents such as CCl4, benzene, and chloroflurocarbons (CFCs), which are either toxic or damaging to the environment. The critical state is achieved when a substance is taken above its critical temperature and pressure (Tc, Pc). Above this point on a phase diagram, the gas and liquid phases become indistinguishable. The physical properties of the supercritical state (e.g., density, viscosity, solubility parameter, etc.) are intermediate between those of a gas and a liquid, and vary considerably as a function of temperature and pressure. The interest in sc CO2 specifically is related to the fact that CO2 is nontoxic and naturally occurring. The critical parameters of CO2 are moderate (Tc = 31 °C, Pc = 74 bar), which means that the supercritical state can be achieved without a disproportionate expenditure of energy. For these two reasons, there is a great deal of interest in sc CO2 as a solvent for chemical reactions. This chapter reviews the literature pertaining to free-radical reactions in sc CO2 solvent.

Sign in / Sign up

Export Citation Format

Share Document