Surfactants engine oils

Two types of surfactants are used in engine oil applications. One is ashless dispersants, and the other is metallic detergents. Typical ashless dispersants, as described in Chapter 15 of Part D (Formulations) of the Handbook of Detergents [8], include succinimides, Mannich condensates, esters, phosphonates, functionalized ethylene-propylene copolymers, and others. Their molecular structures are shown in Figure 13.1. 

Many cracks were observed in HIPS alone for most chemicals tested. For some HIPS/SPS blends, no cracks were observed for some chemicals, although small amounts of cracks were observed in other chemicals. HIPS/SPS blends showed much better chemical resistance than HIPS alone. Thus, HIPS/SPS blends have the potential to be used in the applications where the blend is exposed to chemicals, such as, for example, surfactants, cosmetics, cooking oil, and engine oil. 

Polizelli M, Telis V, Amaral L and Feitosa E. 2006. Formation and characterization of soy bean oil/surfactant/ water microemulsions. Colloids and Surfaces A - Physicochemical and Engineering Aspects 230-236. 

Uses Surfactant intermediate, engine oil lubricant additive, viscosity and pour-point improver, plasticizer, epoxy, antifreeze lubricant, control for leather goods and corrosion inhibitor sizing agent in the alkaline production of paper Features Good thermal stability melt processable cost effective Properties Cl, amber liq, sp, gr, 0,955 vise, 250 cs b.p. 235 5 mm Hg flash pt. (PM-CC)195C... 

Uses Coemulsifler stabilizer detergent dispersant plasticizer and antlstatfor PVAc, food-contact applies. freeze/thaw stabilizer for latexes also for petrol, oils, agric., personal care prods. Intermediate for anionic surfactants corrosion Inhibitor for two-cycle engine oils pQQfurQS Ashloss... 

Uses Used in oil-sol. emulsifiers and detergents dispersant as chem. intermediate for mfg. of lubricants, antlstats, and other surfactants plasticizer and antlstat for PVAc freeze/thaw stabilizer for latex emulsions corrosion inhibitor for small motor engine oils food-pkg. adhesives, paper, polymers Features Alkali and acid stability... 

Alcohol sulfates were first obtained either by the reaction of olefins with sulfuric acid or by sulfation of alcohols produced by hydrogenolysis of oils and fats with sulfuric acid. With the advent of petrochemistry and the progress of chemistry and chemical engineering, alcohol sulfates and their derivatives have become one of the most important surfactants and are produced in large amounts using techniques different from those originally used. They are based on a wide range of alcohols and have found applications in almost all domestic and industrial sectors. 

Concerning the structure of dispersed CLAs, the model originally proposed by Sebba [57] of a spherical oil-core droplet surrounded by a thin aqueous film stabilized by the presence of three surfactant layers is, in our opinion, essentially correct. However, there is still little direct evidence for the microstructure of the surfactant interfaces. From an engineering point of view, however, there is now quantitative data on the stability of CLAs which, together with solute mass transfer kinetics, should enable the successful design and operation of a CLA extraction process. 

Older compilations about the state of the art can be found in several review articles [41 -47]. It is surprising that most work is carried out with the surfactant bis-ethylhexyl-sulfosuccinate (tradename AOT or Aerosol OT). The reasons seem to be the variability of the obtained reverse micelles (from very low up to high water concentrations) and the well-known phase behaviour of AOT with water and several oils [48,49]. AOT is approved for medical application, e.g. as an additive in suppositories, but not for food engineering. 

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