Detergents base number

Table 2.2. Typical parameter values for calcium sulfonates, alkylphenyl sulfides and alkylsalicylates detergents with additional total base number (TBN, mgKOH/g oil) from calcium carbonate. Formation of hard-core reverse micelles (RMs) of calcium carbonate-sulfonate or alkylphenate and soft-core revere micelles (RMs) of calcium alkylsalicylate in oil formulations...

The oil analyses have shown that the TBN values of lubricating oils deplete completely while at the same time, the corrosion rate can be considerably reduced. The relationship between the solubilization of large quantities of acid, total base number (TBN), and total acid number (TAN) values with the rate of corrosion is still unresolved. TAN values are not a good prediction of corrosion, and the source of extra TBN is much more important in the neutralization of corrosive acids than the simple numerical value of TBN. The effect of hard-core RMs shows poor correlation between used oil sample TAN values and the potential for bearing corrosion (Denison, 1944 Kreuz, 1970). Where corrosion rates are reduced by treatment with hard-core reverse micelle detergent, and no significant reduction in TAN has occurred, corrosion protection must have occurred by a... 

The term hard-core RMs is used to describe dispersions containing an excess of colloidal carbonate over that required to neutralize the sulfonic acid. The excess is found in calcium carbonate trapped in a micellar structure. The total base number (TBN) of the additive so obtained is 368 mg KOH/g of oil. The crude additive consisted of 33 wt% CaC03 (Delfort et al., 1995 Giasson et al., 1992). Some typical results of the core particle with the overall diameter and the detergent layer thickness are shown in Table 3.6 (Marsh, 1987). 

The use of TBN alone in defining an overbased detergent is quite misleading. To properly define an overbased detergent, three parameters of the basic material must be determined. Base number, per se, does not specify the metal ratio, that is, the ratio of metal base to substrate, the amount of neutral detergent or soap or the molecular weight of the substrate used. 

Overbased calcium detergents, with base numbers ranging from 250 to 400, form the backbone of the majority of marine lubricants. Although their principal function... 

Traditionally, system oils were simply rust- and oxidation-inhibited mineral oils but the use of high sulphur residual fuels required the introduction of alkaline system oils to provide adequate corrosion protection. A typical system oil now has a BN (base number, see Section 13.8.2) of 5 and sufficient detergency to keep crankcases and piston cooling spaces clean. They are also used to lubricate turbo chargers, stern tubes, deck machinery, geared transmissions and other equipment. 

In diesel lubricants, alkaline reserve neutralizes various oxidation by-products of combustion. However, as the alkaline reserve is consumed, by-product generation increases. Note that overbased detergents do not completely neutralize weak acids and thus allow acidic by-products to increase without a commensurate loss of base number, BN [20]. Determining oil condition based on remaining alkaline reserve, BN, alone is not recommended. 

A.luminum Jilkyl Chain Growth. Ethyl, Chevron, and Mitsubishi Chemical manufacture higher, linear alpha olefins from ethylene via chain growth on triethyl aluminum (15). The linear products are then used as oxo feedstock for both plasticizer and detergent range alcohols and because the feedstocks are linear, the linearity of the alcohol product, which has an entirely odd number of carbons, is a function of the oxo process employed. Alcohols are manufactured from this type of olefin by Sterling, Exxon, ICI, BASE, Oxochemie, and Mitsubishi Chemical. 

A number of these stmctures are offered commercially by BASE Corporation under the trade name Tetronic polyols. The products are similar to oxygen block polymers. Although not strongly surface active per se, they are useful as detergents, emulsifiers, demulsifiers, defoamers, corrosion inhibitors, and lime-soap dispersants. They are reported to confer antistatic properties to textiles and synthetic fibers. 

Sodium dodecylbenzenesulfonate is undoubtedly the anionic surfactant used in the greatest amount because it is the basic component in almost all laundry and dishwashing detergents in powder and liquid forms. However, alcohol and alcohol ether sulfates are the more versatile anionic surfactants because their properties vary, with the alkyl chain, with the number of moles of ethylene oxide added to the base alcohol and with the cation. Consequently, alcohol and alcohol ether sulfates are used in almost all scientific, consumer, and industrial applications. 

While there was a growing number of non-soap detergents that either were already commercialized (as for use in laundry applications) or else had viable commercial potential, it was decided early on to limit the compositional search space to compositions using sodium acyl isethionates (SAI) as the primary surfactant. This decision was based on an early assessment of a prototype bar containing SAI which had been described in a 1952 French patent for which Unilever had acquired the rights [9], This prototype bar, with composition as described in Table 9.2-2, was referred to as the Monsavon bar. 

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