Vinitha Weerasooriya

Optimum Microemulsions Formulated with Propoxylated Guerbet Alcohol and Propoxylated Tridecyl Alcohol Sodium Sulfates

Abstract This is a study of die phase behavior of Propoxylated Guerbet alcohol sodium sulfates C14EX(PO) and C16EX(PO) and Propoxylated tridecyl alcohol sodium sulfates C13(PO) using oil phase composition, water salinity and composition, temperature and propylene oxide number, PON, as variables, show the ability of these surfactants to generate optimum middle phase microemulsions. Optima were found for a wide range of system conditions, e.g. 2% to 16% electrolyte (including Ca++), 30° C to 80°C and octane to hexadecane for the oil phase.

Microemulsion Formation with Chlorinated Hydrocarbons of Differing Polarity

Winsor Type I, Type II, and Type III (middle phase) microemulsions have been produced for water and CCl 4 , water and trichloroethylene (TCE), and water and 1,2-dichlorobenzene (DCB) with anionic surfactants and appropriate electrolytes. Attempts at producing classical phase behavior with several more polar chlorinated hydrocarbons were unsuccessful. These results are compared to those obtained previously with PCE. All studies were done at 25 o C. The erperimental data presented are electrolyte concentration and solubilization parameter for optimum formulations and salinity window for the Type III phase region

TEMPERATURE INSENSITIVE MICROEMULSION PHASE BEHAVIOR WITH NON-IONIC SURFACTANTS

Abstract Non-ionic surfactants with ethylene oxide (EO) head groups become less soluble in water and wourld partition into an oil phase, if present, as system temperatures are raised. Sucrose and glucose based surfactants have the opposite behavior with temperature. This study reports on the ability to make temperature insensitive formulations by using combinations of the above classes of non-ionic surfactants when they are combined in the appropriate mole ratio.

MINIMIZING COSOLVENT REQUIREMENTS FOR MICROEMULSION FORMED WITH BINARY SURFACTANT MIXTURES

ABSTRACT The role of alcohols in microemulsion formation is primarily two-fold. They function as cosolvents by modifying surfactant partitioning between the aqueous and oleic phases and they function as cosurfactants stabilizing microemulsion to the exclusion of unbounaed structures such as liquid crystals, gels or precipitates. Given the freedom of choice among surfactants and their mixtures, the former role of the alcohol can easily be obviated. However, the latter requirement is more fundamental and not so easily removed. This study provides guidance in the purposeful construction of mixtures of synthetic surfactants which can minimize or eliminate alcohol requirements, depending on temperature and salinity. The approach Involves mixing straight tailed (high solubilization parameter) species with mid-chain branched (low cosolvent requirement) species in a spectrum of mole ratios and identifying the minimum alcohol concentration for stable microemulsion. A number of acceptable systems were found.

Synthesis and Performance of Linear Monoisomeric Ethylene Oxide Sulfonate Surfactants

ABSTRACT Reaction of sodium bromoethanesulfonate with sodium alkoxides of several linear alcohols produced linear ethylene oxide sulfonates in good yields These sulfonates were constructed with hydrophobe tails of eighteen and twenty carbons and precisely one, two and three moles of ethylene oxide. All species could be made to produce Winsor III systems with suitable aIkane oil phases and the appropriate salt and coaolvent concentrations.

Surfactant systems for soil and aquifer remediation of JP4 jet fuel

The technology developed for surfactant enhanced oil recovery and toxic spill remediation has been applied to the clean-up of JP4 jet fuel spills on air bases. The EACN for JP4 was determined via previously established mathematical formulae and confirmed experimentally. The physical characteristics of several surfactant systems are described within.