Experimental Equilibrium Constants for the Isomeric Hexanes

Abstract

In the course of the development of the naphtha isomerization process1•2 the equilibrium constants for the isomeric hexanes were determined. Although the equilibrium constants for butanes and pentanes3•4 have been repeatedly investigated, few experimental data have appeared for the hexanes.Two papers5•6 have appeared on the direct experimental determination of the equilibrium constants for the hexanes but they were limited to 25 and 80°, respectively. The hexane equilibria were calculated over a wide range of temperatures from the precise measurements of the heats of combustion and best available entropy data.7 In the present investigation the hexane equilibria were studied directly over the temperature range 21 to 204°and side reactions were reduced to a minimum by the use of hydrogen and cyclic decomposition inhibitors. The experiments were carried out on a fraction of Mid-Continent light naphtha containing both Cfi and Ce hydrocarbons.Packing gland (see detail)(1) B.

Applying Nonlinear Regression to Kinetics of Hexane Isomerization

“…It was found that the" experimentally determined equilibrium values differed from those calculated from the data of Rossini (72); the concentration of 2,2dimethylbutane at equilibrium being lower than the calculated equilibrium value. This observation has also been noted by other investigators (7,77,74). The experimentally determined equilibrium values used in these studies are given in Table IV.…”

Extraction of Sulfur Compounds with Hydrogen Fluoride

“…carbon steel bomb equipped with, a mechanical stirrer operating at 1725 r.p.m. (4). After settling, the hydrogen fluoride extract layer was separated from the supernatant hydrocarbon layer by withdrawal through a valve at the bottom of the reactor.…”

New Data for Estimating Hexane Isomer Equilibrium

“…Work on the direct determination of equilibrium composition (3,4) in the 100°to 400°F. range has shown that the calculated equilibria do not correspond to the observed composition.…”