Oxygen theory combustion

The purpose of this chapter is to alert the interested reader to the potential effects on pollutant emissions by using oxygen-enhanced combustion (OEC). As will be shown, depending on the level of OEC used in a given combustion process, pollutant emissions may either increase or decrease. Specific examples for a given industry are discussed in the application chapters elsewhere in the book. This chapter will give some generalizations and discuss some of the theory that explains the tendencies. 

Materials other than hydrogen can serve as ionic energy carriers too—for example, carbon (as a carbonate ion) and oxides of various elements. In theory, any substance capable of chemical oxidation that can be supplied continuously (as a fluid) can be burned as the fuel at the anode of a fuel cell, Appleby and Foulkes explain. This overall reaction may be viewed as the cold combustion of hydrogen with oxygen —cold combustion... 

The great edifice of modern chemistry has arisen upon the twin foundation-stones of Lavoisier s Oxygen Theory of Combustion and Dalton s Atomic Theory of the constitution of matter. It is ollen overlooked that a period of some twenty years separated these two conceptions, It is true that with the acceptance of Lavoisier s views it could have been said that now sits expectation in the air but meanwhile the dormant science, awakening slowly from its age-long sleep, passed through a confused interregnum, coincident in world history with the rise to power of Napoleon Bonaparte and the consolidation of the former American colonics into a rapidly growing democratic republic. 

As in the solution of the problem of combustion, it was the study of gases that opened the way once again to a decisive advance. The twin foundation stones of Lavoisier s Oxygen Theory and Dalton s Atomic Theory, upon which modern chemistry rests, were both laid as a result of the study of gases. 

The work was of immense importance to the field, but let s note some interesting little flaws that prove that even Lavoisier was not infallible. First, he names vital air as oxygene, which means acid maker. This was reasonable to Lavoisier since combustion of carbon, sulfur, and phosphorus in pure oxygen each produced acids. His oxygen theory of acids was well accepted. This included... 

Determination of the water composition became a major advance of the oxygen theory. In 1781 H. Cavendish observed that inflammable air upon combustion is transformed almost completely (together with dephlogisticated air) into pure water. But he published his results only in 1784. Lavoisier knew about these experiments and, after repeating them, he concluded that water is not a simple substance but a mixture of inflammable and invigorating air. Since the conclusion was made in 1783, Lavoisier is held by many to be the first one to have established the composition of water. In reality, however, H. Cavendish was the first. Determination of the composition of water made it possible to get an insight into the nature of hydrogen. 

The view of the constitution of a gas or elastic fluid held by Lavoisier is like that subsequently adopted by Dalton (see p. 767). The elasticity is due to the tendency of the molecules to separate from one another , and there is some pressure even when they are very rarefied, hence this repulsion is exerted at very great distances. Parts of the memoir are reproduced in a report on the Nomenclature Chimique read by Lavoisier to the Academy on 27 June 1787. For his oxygen theory of acids he refers to the Opuscules (1774, ch. ix), and says of the caloric theory of combustion Rien n est suppose dans ces explications, tout est prouve, le poids et la mesure a la main. . . Quant a nous, qui nous sommes fait une loi de ne rien conclure au deli des faits , etc. etc. ... 

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