Water-Based Oil Spill Dispersants Based on Rosin Formaldehyde Resins

Abstract

Water-soluble surfactants based on rosin acids were synthesized from condensed rosin acid-formaldehyde. This was completed by esterification of series of rosin acid formaldehyde resins with poly(ethylene glycol) having different molecular weights to produce series of rosin esters. The structure of the produced resins was determined by infrared and ¹HNMR analysis. The molecular weight of the produced surfactants was determined by gel permeation chromatography (GPC) technique. The surface properties of the prepared surfactants were determined by measuring the surface tension at different temperatures. The surface tension, critical micelle concentration (CMC), and surface activities were determined at different temperatures. Surface parameters such as surface excess concentration (Γmax), the area per molecule at interface (A_min), and the effectiveness of surface tension reduction (πCMC) were determined from the adsorption isotherms of the prepared surfactants. Some thermodynamic data for the adsorption process were calculated and are discussed. The dispersion efficiency of the prepared surfactants as petroleum oil spill dispersants was determined and correlated with the surface activity, concentrations of the prepared surfactants and type of petroleum crude oil.

Keywords:

• Adsorption
• polyethylene glycol
• rosin derivatives
• surface activity
• thermo-dynamic parameters

Notes

^a Calculated from ¹HNMR analysis.

^b CMC × 10⁴in (mol dm⁻³).

^c γ_CMC in (mNm⁻¹).

SOR: Dispersant Oil Ratio (Dispersant dissolved in water, 40%).

A: The dispersant has very good dispersability.

B: The dispersant has good dispersability.

C: The dispersant has moderate dispersability.

D: The dispersant has bad dispersability.

E: The dispersant has very bad dispersability.