Application of Rhamnolipid in the Formulation of a Detergent

Biosurfactants are a group of surface active agents which are produced by a variety of microorganisms. These materials are safer than their synthetic counterparts regarding the environmental concerns. In this research the application of rhamnolipid (a biosurfactant produced by Pseudomonas aeruginosa) in the formulation of a washing powder was investigated. The biosurfactant was mixed with sodium tripolyphosphate as a builder and sodium sulfate as filler, and was applied to washing pieces of cotton clothes which were contaminated with known amounts of edible oil. The effects of pH and temperature of washing medium, washing time, the stirrer velocity of the washing system, and the weight percentage of rhamnolipid and builder on the washing efficiency of the formulation were examined. The results showed that the biosurfactant was effective in oil removal from the samples. The results moreover showed that the optimum pH was 7, and for the other parameters higher levels gave better results. The formulation presented in this study was also compared with some commercial powders for the removal of edible oil, chocolate, and albumen stains. The results showed that the formulation presented in this study was comparable to commercial powders in terms of the stain removal. Biodegradability tests were also performed on pure rhamnolipid and rhamnolipid in the formulation which confirmed good biodegradability of this biosurfactant.