The Separation of Mixtures of Fatty Acid Derivatives by Continuous Chromatographic Refining

Abstract

A review is given of the factors affecting the performance and
the scale up of chromatographic columns. The industrial separation
of fatty acid derivatives and the application of G.L.C. as a possible
separation method for fatty acids are also reviewed.

The design and construction of a sequential continuous 5
chromatographic refiner (SCCR-2) for high temperature (up to 210°C)
preparative scale G.L.C. separation is described. Counter-current
operation was simulated by sequencing a system of inlet and outlet
port functions around twelve fixed, 2.21 an diameter and 61 cm long
stainless steel columns.

The separation capabilities of the SCCR-2 unit have been
investigated using mixtures of different fatty acid esters. The
feed mixtures selected had separation factors in the range of 1.44-
2.8 and required equipment operation in the range of 105-210°C, while
using OV-275 (a cynosilicone liquid phase) on Chromosorb P, as
chromatographic packing material.

Fatty acid derivatives; ethyl caprylate/ethyl caprate (separation
factor (S.F.) 1.9, 105°C), ethyl caprate/ethyl laurate (S.F. 1.44,
160°C), ethyl laurate/methyl myristate (S.F. 1.54, 185°C) and methyl
myristate/methyl stearate (S.F. 2.8, 206°C) were separated on the SCCR-2
unit. Purities of greater than 99% have been achieved for both product
streams at feed rates of up to 80 an’ h ~ and at an operating,
temperature of 105°C. Lower throughputs; 50, 25 and 20 am"H ~ at
operating temperatures 160, 185 and 205°C respectively were used to
retain the purity in excess of 98.0% for both products.

The experimental results of the separation of binary mixtures at
different temperatures have been compared with the results of a plate
model computation procedure. Results achieved from the theoretical
study indicated partial agreement with the experimental findings.

Date of Award	1980
Original language	English