Fischer-tropsch synthesis in supercritical fluids. Quarterly technical progress report, October 1, 1994--December 21, 1994

Progress reports are presented for the following two tasks: (1) diffusion coefficients of F-T products in supercritical fluids; and (2) Fischer-Tropsch reaction related studies. The objectives for this quarter for task 1 were to measure molecular diffusion coefficients and effective diffusivities at the same conditions. The objectives for task 2 were to conduct two additional tests with the Ruhrchemie catalyst and a catalyst synthesized in our laboratory under supercritical conditions

Diffusion in Liquids

The recently developed Akgerman-Gainer equation to predict diffusion coefficients of gases in liquids employing significant liquid structure theory and absolute rate theory is modified and extended to estimate diffusivitles in liquid-liquid systems and compared with the Wilke-Chang equation. © 1976, American Chemical Society. All rights reserved

Styrene hydroformylation in supercritical carbon dioxide: Rate and selectivity control

Supercritical fluids have the unique characteristic of density-tuned physicochemical properties that can affect reaction rates and selectivities. We have studied homogeneously catalyzed styrene hydroformylation in supercritical carbon dioxide (scCO2) and have shown that the reaction rate and the regioselectivity can be varied by changes in pressure at constant temperature. This rate and selectivity change is explained in terms of the transition state theory. We have determined the partial molar volumes of the reaction products based on the Peng-Robinson equation of state for an infinite-dilution solution model, a real solution model, and a real solution model with regressed interaction coefficients. Then, the estimated partial molar volumes were used to predict the experimentally observed selectivity behavior. Through these simulations, an understanding of the reaction rate and selectivity control by adjustment of the pressure was developed.link_to_subscribed_fulltex

Fischer tropsch synthesis in supercritical fluids: Quarterly technical progress report, July 1, 1996-September 30, 1996

This report describes an equation for predicting diffusion coefficients in supercritical fluids and compares predictions therefrom with literature data. 56 refs., 10 figs., 3 tabs

Fischer Tropsch synthesis in supercritical fluids. Quarterly technical progress report, April 1, 1995--June 30, 1995

Our objective for this quarter was to study the effect of co-feeding a 1-olefin on the Ruhrchemie catalyst activity and selectivity, during-both conventional Fisher-Tropsch synthesis (FTS) and FTS under supercritical conditions. We used propane as the supercritical fluid and 1-dodecene (1-C{sub 12}H{sub 24}) in this test. Motivation for this study was the work of Fujimoto and co-workers who reported that suppression of methane and enhancement of high molecular weight hydrocarbons selectivities occurs with co-feeding of 1-olefins (1-heptene, 1-tetradecene, or 1-hexadecene) during FTS under supercritical conditions, but not during the conventional FTS (Co-La catalyst supported on silica in supercritical n-pentane).The diffusion coefficients of products in supercritical fluids is discussed

Solubility of disperse and mordant dyes in supercritical CO2

Waterless dyeing is the new approach in textile dyeing in order to reduce or eliminate effluent waste, and supercritical carbon dioxide is an alternative solvent being considered. The research focus has therefore been on determination of dyestuff solubilities in supercritical carbon dioxide. We have determined the solubilities of two disperse dyes (C. I. Disperse Yellow 7, C. I. Disperse Oranges 11) and three mordant dyes (C. I. Mordant Brown, C. I. Mordant Yellow 12, and C. I. Mordant Red 11) at 323-343 K and pressures in the range 132-195 bar. Mordant Brown had the highest solubility in the range (1.2-5.1) × 10-4 mole fraction whereas Mordant Yellow 12 had the lowest solubility in the range (1.7-5.1) × 10-7 mole fraction. The disperse dyes and Mordant Red had solubilities of the order 10-6 mole fraction. © 1999 American Chemical Society

Fischer Tropsch synthesis in supercritical fluids. Quarterly technical progress report, January 1, 1995--March 31, 1995

Our objectives for this quarter were: (1) to install and test the temperature probe and the flammable gas detector: (2) to conduct Fischer-Tropsch synthesis experiments at baseline conditions and at a high pressure in order to test the newly constructed fixed bed reactor assembly