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Uses Of Carbon Dioxide As a Supercritical Fluid Essay

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Below is an essay on "Uses Of Carbon Dioxide As a Supercritical Fluid" from Anti Essays, your source for research papers, essays, and term paper examples.

First of all, what is a supercritical fluid? A supercritical fluid is any substance at a temperature and pressure above its critical point, where distinct liquid and gas phases do not exist.It has both the gaseous property of being able to penetrate anything, and the liquid property of being able to dissolve materials into their components. Close to the critical point, small changes in pressure or temperature result in large changes in density, allowing many properties of a supercritical fluid to be "fine-tuned". This high density is associated with the ability of some supercritical fluids to dissolve large nonvolatile molecules.  
Carbon dioxide is in its supercritical fluid state when both the temperature and pressure equal or exceed the critical point of 31°C and 73 atm. In its supercritical state, CO2 provides the ideal conditions for extracting compounds with a high degree of recovery in a short period of time. Near liquid densities increase the probability of interactions between the carbon dioxide and the substrate, similar to a liquid solvent. The gas-like diffusivities of supercritical fluids are typically one to two orders of magnitude greater than liquids, allowing for exceptional mass transfer properties. Moreover, near zero surface tension as well as low viscosities similar to gases, allow supercritical fluids to easily penetrate a microporous matrix material to extract desired compounds. The synergistic combination of density, viscosity, surface tension, diffusivity, and pressure and temperature dependence, allow supercritical fluids to have exceptional extraction capabilities. Many corporations utilize supercritical carbon dioxide to saturate the polymer with solvent (CO2). Upon depressurization and heating the CO2rapidly expands, causing voids within the polymer matrix, i.e., creating a foam.
Carbon dioxide is by far the most commonly used supercritical fluid used in supercritical fluid extraction. The unique solvent properties of supercritical...

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"Uses Of Carbon Dioxide As a Supercritical Fluid". Anti Essays. 17 Dec. 2018

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Uses Of Carbon Dioxide As a Supercritical Fluid. Anti Essays. Retrieved December 17, 2018, from the World Wide Web: http://parimatchstavki7.com/free-essays/Uses-Of-Carbon-Dioxide-As-A-187711.html