Lloyd E. Weeks

A new titrimetric analysis for ethylene oxide condensates

Summary and ConclusionsA critical review of the literature was made in search of suitable methods for analyzing ethylene oxide condensates. These studies led to the development of a rapid empirical titrimetric method for measuring nonionic hydrophobicity based on a water titration of a condensate dissolved in dimethylformamide (DMF) and benzene. The end-point is identified by a definite solution turbidity. Calibration curves were prepared from known condensates.This method should be useful for analysis of adducts in plant quality control and also for nonionics with known hydrophobes. Ether type adducts can not. (Ethylene oxide in esters can be calculated from their saponification values.) Examples of adducts which can be identified by the titrimetric method are those based on fatty alcohols and alkylphenols. Proprietary nonionics analyzed by the DMF method had ethylene oxide values in agreement with those claimed by the manufacturers. DMF data also compare favorably with that by hydriodic acid cleavage.

Analysis of surfactant mixtures

SummaryA scheme has been presented for the separation of active ingredients from built detergent compositions and subsequent analysis of active components. Active components investigated are those commonly encountered in practice. Data obtained are in good agreement with expected values. The main difficulty encountered was the characterization of a fatty alcohol-EO sulfate which gave higher than expected values for its analyzed content. It was also difficult completely to characterize this fatty alcohol-EO sulfate.

Rapid method for determination of unsulfonated oils

A primary limitation to alkylbenzene sulfonation processes has been the lack of a rapid method to sense the quality of sulfonation. This is especially true for a process using sulfur trioxide where both the level of sulfonating agent and time are critical: too little reagent results in high oils; too much reagent degrades product color; and a delay in the process also degrades color. Although steam distillation of oils from the neutralized sulfonate can be conducted in about one and one-half hours for commercial dodecylbenzene derivatives, far greater time is required for higher molecular weight homologs. Extraction of oils requires about one hour and more operator time than distillation.The use of ethylene glycol as the principal carrier solvent, along with a small amount of water, provides oil values within 10 min distillation time. It is also applicable to longer chain alkylbenzene. sulfonates besides those from dodecylbenzene. Subsequently, extracted oils are high, ca. 90%, in sulfone content. Glycol distilled oils plus subsequently extracted oils (sulfones) are slightly greater than oils obtained exclusively by extraction. It has been realized that some of the more volatile oils are lost during the usual extraction procedure.The glycol oils distillation method has been successfully used in plants for alkylbenzene sulfonic acid quality control.

A dynamic foam test for evaluation of hand dishwashing compositions

SummaryA dynamic foam test for evaluation of hand-dish-washing compositions has been developed which gives good correlation with semipractical plate washing tests. Properties measured in the dynamic tests are foam build-up index, foaming capacity, and stability of foam to soil.