Continuous‐throughput rectification of organic liquid mixtures with thermal‐diffusion columns

Abstract

= rate of energy transfer to propellant surface, cal./sec. sq. cm. = gas constant, cal./g. mole OK. = linear burning rate, cm./sec.; ro = burning rate at zero gas velocity = temperature of primary reaction (propellant surface temperature during burning, O K . ) = initial temperature of propellant, OK. = temperature of core gas during burning, O K .= mole fraction A in gas phase = pressure coefficient in empirical burning rate, Equation ( 2 ) = frequency factor in Arrhenius' representation of chemical rate equation = density of solid propellant, g./ cc. Subscripts A, B, D = components in the primary g = core gas i = gas-solid interface surface reaction Experiments were carried out with cylindrical thermal-diffusion columns in which the separation chambers were sufficiently narrow so that curvature effects might be ignored. For both open and closed operation, results were obtained for the two binary systems benzene-carbon tetrachloride and n-heptane-benzene as well as the ternary mixture n-heptane-methylcyclohexane-toluene. For the binary systems, correlations are given in terms of dimensionless combinations which arise when the equations of conservation are placed in dimensionless form. The thermal-diffusion coefficients used in the correlations are literature values determined in steady-state-cell (no convection) measurements.

The effect of column length on separation in thermogravitational thermal diffusion columns

“…In most cases samples were withdrawn from the extreme sample taps only. In Run 5L data were obtained not only at the end taps (7-11) but also at the pair (8)(9)(10). Runs 1OL and 12L represent similar data for a longer column.…”

“…(2-10) (9)(10)(11) AT, "C. The transient data were analyzed in a manner described previously (15). This method of analysis yields a value of ( t / t ) for each transient data point, and these values are listed in Table 1.…”

Thermal diffusion of liquids in columns

“…Several studies have been made of the application of the theory to columns containing liquids. Jones and Furry ( 7 ) presented a thorough review of the subject in 1946; Powers (8,9 ) reviewed the field to 1954; Longmire (10) recently extended the review to 1957. Recent papers concerned with the application of the theory to reservoir-less columns containing liquids are discussed below.…”

“…Longmire (10) investigated the effects of w, AT, and feed concentration on the steady state batch separation and these variables plus feed rate in continuous flow of benzene-carbon tetrachloride, n-heptane-benzene, and one ternary system in annular columns. His conditions of operation were unique in that he frequently approached complete separation.…”

A Comparative Study of Continuous Liquid Thermal Diffusion Systems

“…Parallel-plate, center-feed units have been studied extensively by several investigators {15, 16). Other publications discuss concentric-tube center-feed column operation (/, 8, [11][12][13][14]. The mixed-end feed and the transverse-flow systems have been described recently {3, 4, 5, 7, 9, 10).…”