The chemistry of carbon dioxide

The chemistry of carbon dioxide with transition metal complexes is a field of research that has only recently received wide attention. One goal of research in this area is the development of efficient catalytic processes in which carbon dioxide is reduced by molecular hydrogen and/or incorporated into an organic molecule. Some examples of such desirable transformations... 

In recent years there has been a growing interest in the chemistry of carbon dioxide, stimulated by current anxieties about alternative petrochemical feedstocks. One aspect under active exploration involves carbon dioxide activation via coordination to a transition metal, and indeed transition metal ions do form C02 complexes.177 The number of simple and reasonably stable complexes is still relatively small and usually limited to low oxidation state metal ions. There are many systems where C02 is used as a reagent giving rise to systems which, while not true C02 complexes, may simplistically be viewed as the products of insertion into metal-ligand bonds, e.g. reaction (9), where if L = H, formates are produced if L = OH, carbonates or bicarbonates result L = NR2 yields dialkylcarbamates and if L = R, carboxylate products result. Much of this area has recently been reviewed and will not be considered further.149... 

Almost the entire amount of the carbon available on the earth surface exists in the form of carbonic acid (free or as calcium salts) and in fossil fuels obviously originated from living matter. It is well known that carbon dioxide is the necessary ingredient in the life cycle of animal and plants. Therefore, organic chemistry must be considered as strongly related to the chemistry of carbon dioxide and its derivatives. 

Our recent interest in the chemistry of carbon dioxide (9,12) has included investigations of the synthesis of alkyl formates utilizing CO2 as a source of chemical carbon (Equation 7) (47,48). 

In recent years, interest has intensified in the chemistry of carbon dioxide, stimulated by the current concern about alternate petrochemical feedstocks. One area under active exploration involves C02 activation via coordination to a transition metal complex.1 Several adducts of C02 have been claimed, and two monometallic complexes, with x-ray structures which have been published, are shown below schematically (1 and 2).2,3 We report here two examples of the preparation of 1 1 C02 adducts of a series of rhodium and iridium complexes and, relatedly, methods for preparing the 2 1 C02 lr complex 2. 

Black, Joseph (1728-99) British chemist and physician, born in France. He studied at Glasgow and Edinburgh, where his thesis (1754) contained the first accurate description of the chemistry of carbon dioxide. In 1757 he discovered latent heat, and was the first to distinguish between heat and temperature. 

The chemistry of carbon dioxide corrosion in the oil and gas industry is well-known and will not be discussed here. There are extensive research papers available on that subject [see, for example, Nesic (1995)]. The corrosion rate increases with carbon dioxide partial pressure, due to increased dissolution of the gas into the aque-... 

Hot potassium carbonate processes are intended for the removal of carbon dioxide, or the co-removal of hydrogen sulfide and carbon dioxide. As a result of the regeneration chemistry, these hot-pot processes are not suitable for the removal of hydrogen sulfide without significant carbon dioxide also in the untreated gas stream. 

The reactions and some physical phenomena occurring in the curing paint film have been modelled with special attention being paid to the formation of carbon dioxide (chemistry) and the transport of the carbon dioxide from the paint layer (physics). 

The model describes the kinetics of the chemistry in the paint layer and the transport of carbon dioxide from the paint (physics). 

The transformation of carbon dioxide into useful chemical derivatives is an attractive goal in chemistry. Electroreduction of Pd2(dppm)2Cl2 and Pd(dppm)Cl2 (dppm = bis(diphenylphosphino)-methane) in an aprotic medium under carbon dioxide produces Pd3 (//3-CO)(//-dppm)3.266... 

A full understanding will be needed of the complex chemistry by which the atmosphere and the earth interact, including the dependence of global climate on carbon dioxide concentrations in the atmosphere. Is there a way to deal with the carbon dioxide produced by burning coal and other hydrocarbon fuels so that it causes no problem Chemical scientists will need to investigate effective ways to trap C02 that would otherwise build up in the atmosphere. Alternatively, it will be necessary to find ways to reduce the generation of carbon dioxide. As human... 

The chemistry of carbon, and radiocarbon, in the atmosphere represents one of the most important areas of environmental research today. The primary practical reason for this is the increasing attention which must be paid to the critical balance between energy and the environment, especially from the viewpoint of man s perturbations of natural processes and his need to maintain control. Probably more than other species, carbonaceous molecules play a central role in this balance. Some of the deleterious effects of carbonaceous gases and particles in the atmosphere are set down in Table 3. The potential effects of increased local or global concentrations of these species on health and climate have led to renewed interest in the carbon cycle and the "C02 Problem". It should be evident from the table, however, that carbon dioxide is not the only problem. In fact, the so-called "trace gases and particles" in the atmosphere present an important challenge to our interpretation of the climatic effects of carbon dioxide, itself [20]. 

The decompositions of C302, CO, C02, CS2, COS, CSe2 and COSe are dealt with in this section. Apart from carbon suboxide, this is a group of stable, un-reactive compounds. Considerable emphasis has been placed on the investigation of the photolytic decompositions of some of these compounds which are thought to provide useful sources of atoms (C, O, S and Se) and free radicals (C20). The photochemistry of carbon dioxide has particular relevance to the chemistry of planetary atmospheres, although to date the mechanism of C02 photolysis remains obscure. 

Andrew Dickson (Chair) is an Associate Professor-in-Residence at the Scripps Institution of Oceanography. His research focuses on the analytical chemistry of carbon dioxide in sea water, biogeochemical cycles in the upper ocean, marine inorganic chemistry, and the thermodynamics of electrolyte solutions at high temperatures and pressures. His expertise lies in the quality control of oceanic carbon dioxide measurements and in the development of underway instrumentation for the study of upper ocean biogeochemistry. Dr. Dickson served on the NRC Committee on Oceanic Carbon. He is presently a member of the IOC C02 Advisory Panel and of the PICES Working Group 13 on C02 in the North Pacific. 

Probably an example and problems derived from the carbon dioxide-blood buffer system in humans should be in every physical chemistry course. What a rich, complex example this is from Henry s law for the solubility of carbon dioxide in water (blood) to buffer capacity, that is, the rate of change of the law of mass action with proton concentration. The example can be expanded to include nonideal solutions and activities. How many physical chemistry courses use this wonderful and terribly relevant to life example First-year medical students learn this material. 

Methane is the principal gas found with coal and oil deposits and is a major fuel and chemical used is the petrochemical industry. Slightly less than 20% of the worlds energy needs are supplied by natural gas. The United States get about 30% of its energy needs from natural gas. Methane can be synthesized industrially through several processes such as the Sabatier method, Fischer Tropsch process, and steam reforming. The Sabatier process, named for Frenchman Paul Sabatier (1854—1941), the 1912 Nobel Prize winner in chemistry from France, involves the reaction of carbon dioxide and hydrogen with a nickel or ruthenium metal catalyst C02 + 4H2 —> CH4 + 2H20. 

The present volume is a non-thematic issue and includes seven contributions. The first chapter byAndreja Bakac presents a detailed account of the activation of dioxygen by transition metal complexes and the important role of atom transfer and free radical chemistry in aqueous solution. The second contribution comes from Jose Olabe, an expert in the field of pentacyanoferrate complexes, in which he describes the redox reactivity of coordinated ligands in such complexes. The third chapter deals with the activation of carbon dioxide and carbonato complexes as models for carbonic anhydrase, and comes from Anadi Dash and collaborators. This is followed by a contribution from Sasha Ryabov on the transition metal chemistry of glucose oxidase, horseradish peroxidase and related enzymes. In chapter five Alexandra Masarwa and Dan Meyerstein present a detailed report on the properties of transition metal complexes containing metal-carbon bonds in aqueous solution. Ivana Ivanovic and Katarina Andjelkovic describe the importance of hepta-coordination in complexes of 3d transition metals in the subsequent contribution. The final chapter by Sally Brooker and co-workers is devoted to the application of lanthanide complexes as luminescent biolabels, an exciting new area of development. 

J. Black s investigation 3 of 1756 is the first contribution to the chemistry of the carbonates of ammonia, and he pointed out the chemical difference between the aqua ammonia and the solid carbonate of commerce. J. Priestley also, in 1774, dwelt on the same subject. T. Bergmann analysed the commercial carbonate in 1774 H. Davy emphasized the variable nature of the compounds of carbon dioxide and ammonia in 1799 while C. L. Berthollet (1806) and J. Dalton (1819) demonstrated that there are several different carbonates of ammonia. In his paper On the combinations of carbonic anhydride with ammonia and water (1870), E. Divers showed that there are at least three well-defined ammonium carbonates—the normal carbonate, the hydrocarbonate, and the sesquicarbonate. On the other hand, in his paper Ueber die Verbindungen des Ammoniaks mit der Kohlensaure (1839), H. Rose claimed to have shown that an indefinitely large number of these compounds can be prepared, and he described twelve of them. He said ... 

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