Refractive index of alcohol nonionics

Refractive index is a rapid and consistent method of analysis for alcohols and nonionics from normal alcohols and ethylene oxide. Correlations of refractive index with hydroxyl number of alcohols and nonionics are excellent and measurement error is considerably lower for refractive index. Refractive index affords a measurement of the amount of ethylene oxide in nonionics and can be used as a replacement for the 1% cloud point analysis. The ethylene oxide adduct distribution has no effect on refractive index. Specific adducts, a narrow range of adducts made by acid catalyzed ethoxylation and a broad range of adducts made by base catalyzed ethoxylation give the same refractive index value for any given ethylene oxide content. Applications for the refractive index method for the laboratory and plant are: alcohol blending control, calculation of ethylene oxide requirements for ethoxylation, nonionic control analysis, calculations of hydroxyl number for sulfations. Also, refractive index can help identify laboratory samples, indicate the 1% cloud point and predict the phase character of nonionics.