Carbon dioxide uses for

Solid carbon dioxide is shown in Figure 11.1. It has an interesting property at normal pressures it passes directly to the gaseous state without first melting to the liquid. This property, together with the fact that this change occurs at -78°C, makes solid carbon dioxide useful for keeping materials very cold. Because solid CO2 cools other objects and does not leave a liquid residue, it is called dry ice. 

Carbon dioxide used in carbonated beverages must be food-grade and must meet the Compressed Gas Association commodity specifications for carbon dioxide. In addition, carbon dioxide is tested for purity, taste, and odor before being used in the production of beverages. 

The use of carbon dioxide gas for shielded arc welding with semiautomatic microwire welding equipment has led to welding speeds up to 10 times those obtainable within conventional equipment. No cleaning or wire bmshing of the welds is required (45) (see Welding). 

Figure 12-14J. Compressibility chart for low-pressure carbon dioxide. (Used by permission Form 3519 D (1981), 1960. Ingersoll-Rand Company. All rights reserved.)...

Purple sulfur bacteria fix carbon dioxide using the Calvin-Benson cycle, but green sulfur bacteria use a completely different pathway, the reverse tricarboxylic acid cycle. Other photosynthetic bacteria use still different pathways for CO2 fixation (Perry and Staley, 1997). 

They do differ in one respect from their filamentous siblings in that they are able to metabolise certain carbohydrates (sugars) by a process known as fermentation. During this, of course, they produce alcohol and gas (carbon dioxide) and for that reason they are used in brewing, bread making and other useful processes. 

Carbon Dioxide Separation for Fuel Reforming Carbon dioxide separation reforming in the above mentioned is one of useful methodologies for efficient hydrogen production [29]. Calcium oxide (CaO) carbonation can absorb CO2 from the reformed gas and fix it. 

UTI A process for making urea from ammonia and carbon dioxide, using heat-recycle. Invented in 1970 by I. Mavrovic in New York. 

A unique methodology for the generation of nanoporous thin films using supercritical carbon dioxide (SCCO2) for potential nanolithographic applications was introduced in 2004 by Li et al. [53]. In this work, thin films of PS-poly(perfluorooctylethyl methacrylate) [PFMA] were spin-cast onto sili-... 

This type of system may be used for the extinguishment of surface fires in flammable liquids, gases, and solids where the hazard is not enclosed. Examples of hazards that may be successfully protected by local application systems include dip tanks, quench tanks, and spray booths. Since local application systems do not utilize enclosures to maintain design concentrations, two methods for determining the quantity of carbon dioxide required for extinguishment are used. These are ... 

Carbon and oxygen isotope compositions of sixteen marbles from epidote amphibolites of the Sambagawa metamorphic belt and of three diamondbearing marbles from the Kumdy-Kol area of Kokchetav Massif were measured. Powdered calcite from the marbles was decomposed by 100 percent phosphoric acid at 60°C to obtain carbon dioxide gas for isotopic analyses. Isotopic measurements were carried out using a triple-collector mass spectrometer (Finnigan MAT Delta E). All data are given in terms of a conventional expression in... 

The most desirable choice, of course, would be water, since it has essentially no harmful effects on humans or the environment. The problem is that most organic substances do not dissolve in water. One of the most exciting alternatives with promise for use in organic syntheses, however, is another widely available and environmentally benign compound, carbon dioxide. The carbon dioxide used in organic reactions exists in a phase not generally familiar to most people, the supercritical phase. 

M. M. Hal man n, Chemical Fixation of Carbon Dioxide Methods for Recycling C02 into Useful Products, CRC Press, Boca Raton, FL, 1993. 

Appendix A has no chart for K-values of carbon dioxide. At low concentrations of carbon dioxide use... 

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