Potential of binary mixtures of sodium lauryl sulfoacetate (SLSA) and alkyl polyglucoside (APG10) as oil degreaser

Abstract The industry is challenged to replace toxic chemical-based surfactants with environmentally friendly and biodegradable surfactants. In this study, binary mixtures of sodium lauryl sulfoacetate (SLSA) and an alkyl polyglucoside (APG10) in various proportions were investigated for their effectiveness as degreasing agents. Efficacy was characterised using surface tension measurements, oil dispersion tests, emulsification, pH and cleaning efficacy in removing engine oil from a metal plate. The surface tension results for all solutions showed a critical micelle concentration of 1500 ppm. The dispersion tests (with oil:surfactant ratios of 1:2 and 1:3) showed that the oil was fully dispersed at an oil:surfactant ratio of 1:2 i.e., at a concentration of 2500 ppm SLSA and 2000 ppm of a binary solution with a volume ratio of SLSA:APG10 of 75:25. At a ratio of 1:3, the oil was fully dispersed with 2500 ppm of a binary solution with a ratio of SLSA:APG10 of 75:25. Overall, the solution with a volume ratio of SLSA:APG10 of 75:25 was the most favourable. The results also showed that a solution containing only SLSA had good potential as a degreaser, as it achieved a cleaning performance of 90% in removing oil from the metal plate despite low emulsification levels (E24) for both surfactants. In summary, a combination of these two green surfactants can be used effectively as a degreasing agent.