부산대학교 도서관

High pressure supercritical carbon dioxide efficiency in removing hydrocarbon machine coolants (production process contaminants) from metal coupons and component parts was evaluated. Solubility experiments were performed on Cimperial 1011, Cimperial 15, Gulfcut 11D machine coolants. Extraction experiments were conducted on machine coolant contaminated aluminum and 303 stainless steel coupons as well as detonator production components. The solubility/fractionation experiments were conducted in a screening supercritical carbon dioxide system. The solubilities of Cimperial 1011 and Cimperial 15 were measured at 50{degrees}C, 13.8 Mpa. The solubilities of Cimperial 1011 and Gulfcut 11D were also measured at 35{degrees}C, 13.8 Mpa. In addition, coolant fractions were collected for gas chromatography analysis. Extraction experiments were conducted in a supercritical carbon dioxide feasibility system, utilizing a 300 mL process vessel. Cleaning trials were conducted at 35{degrees}C, 13.8 Mpa with carbon dioxide contact times of 15--30 min. Residual machine coolant concentrations on coupons and components were determined by a hexane rinse/capillary gas chromatography analysis procedure. This study has demonstrated under the stated experimental conditions that high pressure supercritical carbon dioxide shows potential as a cleaning media for removing hydrocarbon machine coolants from metal substrates. The use of such a process is optimized in production cleaning applications would reduce plant waste streams significantly.