Title of Dissertation: HEAT TRANSFER AND MECHANICAL DESIGN ANALYSIS OF SUPERCRITICAL GAS COOLING PROCESS OF CO2 IN MICROCHANNELS Guohua Kuang, Doctor of Philosophy, 2006 Directed By: Professor Michael Ohadi, Department of Mechanical Engineering Professor Balakumar Balachandran (Co-Advisor), Department of Mechanical Engineering An extensive review of the literature indicates a lack of systematic...

The CO2-brine dissolution homogenizes the distribution of residual CO2 and reduces the leakage risk in the saline aquifer. As a key parameter to immobilize the free CO2, the dissolution rate of CO2-brine could be accelerated through mechanisms like diffusion and dispersion, which are affected by the subsurface condition, pore structure, and background hydrological flow. This study contributed t...

supercritical fluid extraction (scfe) is a soil remediation technology. at present, only a few companies are using from this method, all of which are technical based on conventional methods of extraction such as soilex solvent extraction. because of the hard enforcement of environmental conservation law, using green technology seems imperative. this paper endeavors to carry out the feasibility ...

The behavior of polymeric surfactant polyvinyl acetate (PVAC)-b-poly(1,1,2,2-tetrahydroperfluorooctyl acrylate) (PTAN) in supercritical carbon dioxide (CO2) was investigated using static and dynamic light scattering. We observed three regions on the phase diagram of the copolymer in supercritical CO2: (i) two-phase region at low CO2 density; (ii) solutions of spherical micelles at intermediate ...

The ring hydrogenation of benzoic acid to cyclohexanecarboxylic acid over charcoal-supported transition metal catalysts in supercritical CO2 medium has been studied in the present work. The cyclohexanecarboxylic acid can be produced efficiently in supercritical CO2 at the low reaction temperature of 323 K. The presence of CO2 increases the reaction rate and several parameters have been discussed.

dissolution pressure and nozzle temperature effects on particle size and distribution were investigated for ress (rapid expansion of supercritical solution) process. supercritical co2 was used as solvent and ibuprofen was applied as the model component in all runs. the resulting ibuprofen nano-particles (about 50 nm in optimized runs) were analyzed by sem and laser diffraction particle size ana...

BACKGROUND Caryocar brasiliense Camb (Pequi) is a typical Brazilian Cerrado fruit tree. Its fruit is used as a vitamin source for culinary purposes and as a source of oil for the manufacture of cosmetics. C. brasiliense supercritical CO2 extracts exhibit antimicrobial activity against the bacteria Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus and also possess antioxidant a...

Abstract: A thermodynamic consistency test developed for high pressure binary vapor-liquid mixtures is applied to mixtures containing a supercritical solvent and an ionic liquid. Several authors have reported vapor-liquid equilibrium data on the binary systems supercritical CO2 + 1-butyl-3-methyl imidazolium hexafluorophosphate {[bmim][PF6]}, supercritical CO2 + 1-butyl-3-methyl imidazolium nit...

BACKGROUND Waste animal fat is a promising feedstock to replace vegetable oil that widely used in commercial biodiesel process, however the high content of free fatty acid in waste fat makes it unfeasible to be processed with commercial base-catalytic process. Enzymatic process is preferable to convert waste fat into biodiesel since enzyme can catalyze both esterification of free fatty acid and...

a mathematical model is described and applied for adsorption process of ethyl acetate from supercritical co2 stream on activated carbon particles. this model has the ability of illustrating variation of effluent concentration towards different parameters such as flow rate, temperature and pressure. in this research, a vast area of operational conditions is experienced. mass transfer resistance ...