Sulphonated Methyl Ester a promising surfactant for detergency in hard water conditions
We report results on the physical phase behavior of sulphonated methyl esters in different water hardness conditions. We also compare its foam performance against a number of other surfactants in correlation with their Kraftt points at different levels of water hardness. Whilst SME is slightly behind in terms of solubility in deionized water it gains ground as the level of water hardness goes up and is significantly better when certain mixtures are used. The best results are observed at 1:1 ratio for Kraftt point as well as for foam performance. The results suggests potential applications for this relatively new palm oil derived surfactants, namely in regions with high levels of water hardness.
Sulphonated methyl esters (SME) have been identified quite some years back as a green alternative to the current surfactant leader of the Home Care market - the linear sodium alkyl benzene sulphonate (LAS), as well as alpha olefin sulphonates (AOS), primary alcohol sulphate (PAS) and alcohol ethoxylated sulphate (AES) which are predominantly petrol derived (1, 6). With the increased awareness of leading Fast Moving Consumer Goods (FMCG) companies with regard to preserving the scarce planet resources for the future generations, i.e. doing business in a sustainable manner, the demand for renewable and highly performing substitutions of the current petrol based surfactants has never been stronger. The sulphonated methyl esters are also non-toxic, very mild and easily bio-degradable (7, 10). One drawback in the last couple of years has been the drop in the crude oil price, due to a complex set of reasons, which had a negative impact on the penetration of SME in the Home Care market. Irrespective of the cost advantage the LAS might have at the moment, the surfactants for detergency are also selected and graded on their performance in, sometimes, challengin ...