Brian N. Hansen

Deposition of palladium films by a novel supercritical fluid transport-chemical deposition process

Abstract Palladium was pyrolytically deposited by a supercritical fluid transport-chemical deposition method using the metal β-diketonate complex bis-(2,2,7-trimethyl-3,5-octanedionato)palladium(II). Deposition at a rate of 95 nm/min occurred at a substrate temperature of 740 °C. X-ray diffraction and electron microprobe analyses of the reflective films that were deposited on fused silica substrates showed that they contained polycrystalline palladium. The films were electrically conductive, but conductivity was substantially lower than that for bulk palladium. X-ray diffraction of the films deposited on (100) Si substrates showed that palladium silicide was formed.

Solubility of pure taxol in supercritical carbon dioxide

Abstract The solubility of taxol in supercritical carbon dioxide was measured using a high-pressure ultraviolet–visible-light-transmission static cell at pressures from 3000 psia to 7000 psia and temperatures 35°C to 45°C. The solubility of taxol increased by a factor of seven from 0.7×10 −7 to 5.0×10 −7 mole fraction from 3000 psia to 7000 psia. The experimental data were modeled using the Peng–Robinson equation of state and the Chrastil method. The Peng–Robinson equation of state method utilizing k 12 optimum did not provide an adequate fit. The Chrastil method provided a good fit with average absolute relative deviations of 4.6%, 3.6%, and 2.8% for 35°C, 40°C, and 45°C, respectively.

Solubility measurement by direct injection of supercritical-fluid solutions into a HPLC system

Abstract A new apparatus has been built for measuring solubility of solutes in supercritical fluids by direct injection of saturated supercritical-fluid solutions into a high-performance liquid chromatograph. To test the system, we measured the solubility of solid naphthalene in supercritical carbon dioxide at 55 °C for pressures between 6.58 and 10.23 MPa. The system was designed to operate at pressures and temperatures up to 34 MPa and 140 °C.

High‐pressure equilibrium cell for solubility measurements in supercritical fluids

This paper describes the design, construction, and operation of an ultraviolet‐visible light‐transmission cell for high‐pressure fluids. The cell can be operated at pressures as high as 70 MPa and at temperatures up to 100 °C. This instrument was specifically designed to measure the solubility of solutes in supercritical fluids. The cell has an internal saturator and fluid circulator that are easy to remove and clean. The solubility of ferrocene in supercritical carbon dioxide was measured in the high‐pressure cell described here. At 40 °C, the mole fraction of ferrocene in carbon dioxide increased from 0.00005 to 0.0015 as the solvent density was increased from 5 to 17 mol/L.