Emulsification with

At the refinery, before distillation, the salt content is often further reduced by a second emulsification with freshwater, followed by demulsification. Crude oils with high salt contents could lead to breakdowns and corrosion at the refinery. The object of using an emulsion breaker, or demulsifier, is to break the emulsion at the lowest possible concentration and, with little or no additional consumption of heat, to bring about a complete separation of the water and reduce the salt content to a minimum. 

Methods of fixing the volatile aroma and flavor compounds separately from the instant coffee powder have been developed. The volatile mixture can be mixed with aqueous gelatin or gum arabic and spray dried. The oily droplets of the flavor and aroma compounds are coated with gelatin or gum arabic in a dry lattice. This powder can be mixed in with instant coffee powder and is relatively stable in the presence of air. Emulsification with sugar is also a highly effective way of trapping and preserving coffee volatiles, but is of limited use for instant coffees. 

Paraffin hydrocarbons of molecular mass 300 to 700 (i.e. 20-50 carbon atoms) require emulsification with surfactants. They show good resistance to oxidation and yellowing. 

In our series, full retinal reapplication was achieved in 16 of 17 patients (95%). There was only one case of major emulsification immediately after surgery. This was consistent with Wolfs results [47], who reported no case of emulsification with Oxane Hd . Only once did we note silicone passage into the anterior chamber. Wolf reported the post-operative passage of heavy silicone oil (1.03 g/cm ) into the anterior chamber in two aphatic patients despite superior peripheral iridectomy. The incidence of post-operative glaucoma was lower in our series than that reported by Wolf [47] and other publications on standard silicone oil complications [16,17]. Heavy oil removal was uneventful in all patients in Wolfs series, who used 1.03 g/cm density silicone oil. Likewise, in all our patients operated on with the same density (1.03 g/cm ) heavy silicone oil (17 eyes), active extraction with the extraction module of the vitrectomy apparatus posed no problem. 

It is unique because of its powerful hydrogen bonding character and its distinct polarity. However, in fuel systems, these characteristics of water make it a source of a variety of problems. Corrosion of metal fuel system components, emulsification with fuel performance additives, and ice formation in fuel lines are some of the problems directly related to the presence of water in fuel. 

Fuel system corrosion inhibitors must have a low tendency toward emulsification with water and toward foam enhancement in turbulent systems. These properties are especially critical whenever inhibitors are used in jet fuel. The sensitivity of jet fuel pumping and injection systems requires that fuel be free of emulsions and foam. 

Emulsions are two-phase systems formed from oil and water by the dispersion of one liquid (the internal phase) into the other (the external phase) and stabilized by at least one surfactant. Microemulsion, contrary to submicron emulsion (SME) or nanoemulsion, is a term used for a thermodynamically stable system characterized by a droplet size in the low nanorange (generally less than 30 nm). Microemulsions are also two-phase systems prepared from water, oil, and surfactant, but a cosurfactant is usually needed. These systems are prepared by a spontaneous process of self-emulsification with no input of external energy. Microemulsions are better described by the bicontinuous model consisting of a system in which water and oil are separated by an interfacial layer with significantly increased interface area. Consequently, more surfactant is needed for the preparation of microemulsion (around 10% compared with 0.1% for emulsions). Therefore, the nonionic-surfactants are preferred over the more toxic ionic surfactants. Cosurfactants in microemulsions are required to achieve very low interfacial tensions that allow self-emulsification and thermodynamic stability. Moreover, cosurfactants are essential for lowering the rigidity and the viscosity of the interfacial film and are responsible for the optical transparency of microemulsions [136]. 

Referring to Table 4.8, there are differences between the two homogenizers and types of particle size analysis. However, an independent study (Gooch 2002) showed that emulsification with an APV Homogenizer (3,500 psig) produced an emulsion with a mean particle size of 0.688/1.128 pm (number/volume-weight geometric mean). 

Fig. 51 Process equation in emulsification with jet emulsifier according to Fig. 50 from [75].The fitting line corresponds to the eq. (12.75).

When the minimum of y with respect to T is negative (Fig. 3), the interfacial tension is negative in the range of temperatures in which the curve y = y(T) intersects the abscissa. A negative y makes the water oil interface unstable to thermal and mechanical perturbations and a spontaneous emulsification with the formation of globules of oil in water and water in oil takes place. At low temperatures, because of coalescence, only a fraction of the globules of oil survive... 

Since lipases act on lipids at lipid-water interfaces, preparation of substrates in a suitable physical form for maximal lipase activity is very important. Preparation methods include emulsification with an emulsifying agent incorporation into a gel dissolution in a water-soluble organic solvent, such as 2-methoxyethanol or tetrahydrofuran, followed by addition to an aqueous reaction mixture sonication, with or without emulsifier and formation of a thin film or monolayer. 

For removal of insoluble and/or water-immiscible inorganics by emulsification with detergent solutions For removal of ester and amide-based organics and inorganic salts by chemical hydrolysis with alkaline solutions For removal of metal ions from solutions and surfaces by chelation or complexation reactions For wetting and dispersion of soils with surfactants, suspension of soil residues in order to prevent resedimentation and recontamination on metal surface For removal of surface contaminations, rust scale, mill scale, and other bound moieties (including surface layers of metal itself) by chemical dissolution with acids or alkaline deoxidation with or without the application of an electric current... 

Figure 7. Fat surface area of the protein-stabilized emulsions as a function of power consumption after emulsification with a valve homogenizer using 10 passes through the recirculating system ( ll,)...

Kelder, J.D.H., Janssen, J.J.M., and Boom, R.M. (2006). Membrane emulsification with vibrating membranes a numerical study, submitted. 

Emulsification with caustic is possible with oils that have a fairly high total acid number (TAN). Below about 1.5 mg KOH/gm oil, the oils either will not emulsify or will form water-in-oil emulsions. The rate of emulsification with caustic is much faster than emulsification with surfactant mixtures, which is a characteristic property for emulsions generated via the agent-in-oil procedure (1 ). 

Further research is needed on the influence of the viscosity of the continuous phase on US emulsification with a view to assess the significance of cavitation as a droplet disruption mechanism. 

Wieringa j., Kieft V., Emulsification with static mixers, Chem.-Ing. Tech. 68 (1996) 9, p. 137... 

Significant studies prove the interest in this kind of membrane. Among them we mention the work of Lambricht and Schubert [17] on emulsification with microchannels, and the study of Popat et al. [18] that proves that the bone cell response can be significantly improved using controlled nanoarchitecture (alumina membranes fabricated using a two-step anodization process and which present pore sizes of 30-80 nm). 

In order to continue the comparison of the aqueous sodium hydroxide dehydrochlorination with the aqueous sodium hydroxide/ sodium carbonate method the organic phase from the above reaction was removed and retreated with aqueous sodium hydroxide (a further 2 molar excess). Ultimately a 98% conversion to glycidyl 2-ethylhexanoate was achieved but by this time very extensive epichlorohydrin hydrolysis had occurred (56%). It was also found difficult to separate the organic phase from this reaction due to emulsification with the aqueous phase in order to carry out the final purification stage by distillation. 

As a new option, for the bioconversion of poorly soluble substrates the classical EMR-concept can be extended to an Emulsion Membrane Reactor , comprising a separate chamber for emulsification (with a hydrophilic ultrafiltration membrane), an EMR-Ioop with a normal ultrafiltration module, and a circulation pump. This approach has been successfully demonstrated for the enzymatic reduction of poorly soluble ketones [107]. Using this device, e.g., for the enantioselective reduction of 2-octanone to (S)-2-octanol (e.e. >99.5%) with a carbonyl reductase from Candida parapsilosis under NADH-regeneration with FDH/for-mate, the total turnover number was increased by a factor 9 as compared with the classical EMR. 

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