Cold Water Detergency of Triacylglycerol Semisolid Soils: The Effect of Salinity, Alcohol Type, and Surfactant Systems

Abstract

Cold water detergency of triacylglycerol semisolid soils is much more challenging than liquid vegetable oils due to poorer interaction between surfactants and semisolid soil. This research seeks to improve the removal efficiency of semisolid soils below their melting points using surfactant‐based formulations containing different alcohol additives. To this end, cold water detergency of solid coconut oil and solid palm kernel oil was investigated in various surfactant/alcohol systems, including single anionic extended surfactants, single nonionic alcohol ethoxylate surfactants, and a mixture of anionic surfactants. A series of alcohols (2‐butanol, 1‐hexanol, 1‐heptanol, 1‐octanol, 1‐nonanol, and 1‐decanol) were added to the surfactant formulations to investigate cold water detergency improvement. While cold water detergency using surfactants alone was poor, it was considerably improved when optimum salinity (S*) and 1‐heptanol, 1‐octanol, or 1‐nonanol were introduced to the studied surfactant formulations. The maximum detergency of solid coconut oil exceeded 90% removal in the 0.1 w/v% C14‐15‐8PO‐SO4Na/0.2 w/v% 1‐octanol/4 w/v% NaCl system (a final optimized surfactant system) at a washing temperature of 10°C versus 22.9 ± 2.2% in the surfactant alone (not at optimum salinity and no additive). Further analysis showed that improved cold water detergency using surfactant/intermediate‐chain alcohols/NaCl could be correlated with high wettability (low contact angle) as well as favorable surfactant system‐soil interaction as observed by lower interfacial tension values. In contrast, the improved cold water detergency was observed to be independent of dispersion stability. This work thus demonstrates that surfactant system design, including additives, can improve cold water detergency of semisolid soils and should be further explored in future research.

Effect of Surfactant Systems, Alcohol Types, and Salinity on Cold‐Water Detergency of Triacylglycerol Semisolid Soil. Part II

“…Chanwattanakit et al (2017) found that the cold-water detergency of methyl palmitate, the semisolid soil used in their study, was about 25% removal at 15 C and 30% removal at 20 C using 0.1 wt% C 12-13 -4PO-SO 4 Na at 5 wt% NaCl. Similarly, our previous work (Phaodee et al, 2019) reported that coldwater detergency of coconut oil was approximately 20% removal using 0.1 w/v% C 14-15 -8PO-SO 4 Na alone and 50% removal using C 14-15 -8PO-SO 4 Na at 8 w/v% NaCl (S*), which was found to demonstrate the lowest IFT. These prior results demonstrate that cold-water detergency of semisolid soils using a single surfactant alone is often inadequate.…”

“…For the 50% linearity surfactants, even though the minimum IFT was below <1 mN m −1 range (Fig. ), which has been shown to be a desired IFT range for detergency of various soils (Attaphong and Sabatini, ; Phaodee et al, ; Tongcumpou et al, ), the detergency performance was still much lower than for the branched C 14‐15 ‐8PO‐SO 4 Na surfactant. There is evidence that branched‐extended surfactant with the insertion of PO group showed lower IFT, thus better detergency (Fig.…”

“…The decreasing relative hydrophobicity of the oil with the presence of the lipophilic linker required lower S* to attain the optimum surfactant formulation, where minimum IFT and maximum solubilization were achieved (Acosta et al, 2003a;Graciaa et al, 1993;Sabatini et al, 2003;Salager et al, 1979;Salager et al, 2019). Evidence has shown that this behavior correlates with detergency of triacylglycerol semisolid soils as well (Mankowich, 1963;Phaodee et al, 2019).…”

Extended Surfactants Including an Alkoxylated Central Part Intermediate Producing a Gradual Polarity Transition—A Review of the Properties Used in Applications Such as Enhanced Oil Recovery and Polar Oil Solubilization in Microemulsions

“…It was thus a long time after Miñana introduction of such solubilization properties with natural oils that extended surfactants were studied as performant ingredients for ordinary or special detergency effects (Attaphong and Sabatini, 2017;Chanwattanakit et al, 2017;Phaodee et al, 2019;Smith and Hand, 2006a;Tanthakit et al, 2010).…”

Cleaning Ability of Mixed Solutions of Sulfonated Fatty Acid Methyl Esters

“…Indications that the soil detachment can depend on the surfactant alkyl chainlength (Gambogi et al, ; Lim et al, ; Siwayanan et al, ) and headgroup nature (Mahdi et al, ) have been found. The oil/water interfacial tension is also an important factor for oil drop detachment (Phaodee et al, ). Another governing factor is expected to be the surface energy of the solid substrate, which significantly depends on the surface type, treatment, aging, and so on.…”