Use of Alumina Support for the Separation of Ethoxylated Oligomer Surfactants According to the Length of the Ethyleneoxide Chain

Abstract

The theoretical plate number, capacity factor, peak assymetry and separation factor of an alumina high-performance liquid chromatographic column were determined using nonylphenyl ethylene oxide oligomers as solutes and eluents containing n-hexane, dichloromethane, dioxane, tetrahydrofuran, chloroform and ethyl acetate. The relationship between the chromatographic characteristics and physicochemical parameters of the stronger component in the eluent was calculated by multivariate mathematical-statistical methods. It has been established that each solvent influences differently the chromatographic characteristics. The best separation was achieved by using n-hexane - dichloro-methane eluent. Calculation proved that the dielectric constant, dipole moment and the bulkiness of the solvent molecule have the highest impact on the separation capacity of the alumina column.

Key Words:

• alumina HPLC column
• nonylphenyl ethylene oxide oligomers
• separation parameters