Lower cloud point

Lower cloud point in the diesel fuel. Isoparaffins in the light cycle oil boiling range improve the cloud point. 

The cloud point test is one of the most commonly used methods to evaluate the low-temperature characteristics of distillate fuel. The cloud point temperature identifies the point when wax begins to form into crystals large enough to become visible in the fuel. At this temperature, wax can settle from fuel, deposit onto fuel filters, and interfere with the flow of fuel through small tubes and pipes. During cold weather months, distillate fuels with lower cloud point values are refined and blended to minimize the low-temperature problems associated with wax. 

LCP lower cloud point LNP hquefied natural petroleum... 

Mixtures of Brij 96 and Brij 92 in water, in which the latter was solubilized by the former up to 157o, gave lower cloud points and higher... 

Oxyethylated FAME exhibits the surface-active and nsage properties similar to typical nonionic surfactants, including oxyethylated alcohols [25,49-64]. It is obvious that there are some differences, connected with the somewhat different structure, that is, the presence of a terminal methyl group. As a result, oxyethylated FAME show lower foaming ability, lower clouding points, and different tendency for gelation. 

Detergent, foaming and suspending agent. Produces rich foam. Primary surfactant in rug shampoos, upholstery shampoos and spot removers. Good viscosity response to additions of salt and alkanolamides. Exhibits lower cloud point (lower solidification point) than SLS, permitting easier handling in colder weather. SULFOCHEM SLN ... 

A hydrotrope, a solubilizer used to lower cloud point and viscosity. Especially good for dry compounding. 

Surfactant with increased solubility and lower cloud point viscosity stabilizer in natural soap systems. 

The material prepared from the lower-molecular-weight fraction is commercially referred to as dodecylbenzene and the higher, as tridecylbenzene. The so-called tridecyl material is actually a mixture of mostly C12 and C14 isomers the exact mixture depends on the manufacturer. The tridecylbenzene sulfonate, in general, shows better detergent properties and better foaming in soft water, whereas dodecylbenzene sulfonate has a lower cloud point and better viscosity behavior in liquid formulations. 

At lower temperatures, the crystals increase in size, and form networks that trap the liquid and hinder its ability to flow. The pour point is attained which can, depending on the diesel fuel, vary between -15 and -30°C. This characteristic (NF T 60-105) is determined, like the cloud point, with a very rudimentary device (maintaining a test tube in the horizontal position without apparent movement of the diesel fuel inside). 

The nature of these paraffins and their concentration in diesel fuel affect the three temperatures that characterize the cold behavior. The cloud point is the temperature at which crystals of paraffins appear when the temperature is lowered. The cold filter pluming point is defined as the temperature under which a suspension no ionger flows through a standard filter. Finally, the pour point is the temperature below which the diesel fuel no longer flows by simple gravity in a standard tube. These three temperatures are defined by regulations and the refiner has three types of additives to improve the quality of the diesel fuel of winter. 

Some additives have the ability to lower the pour point without lowering the cloud point. A number of laboratory scale flow tests have been developed to provide a better prediction of cold temperature operability. They include the cold filter plugging point (CFPP), used primarily in Europe, and the low temperature flow test (LTFT), used primarily in the United States. Both tests measure flow through filter materials under controlled conditions of temperature, pressure, etc, and are better predictors of cold temperature performance than either cloud or pour point for addithed fuels. 

Cloud point. Measures the solubility/compatibility of a resin with solvents. The value reported is the temperature at which a specific mixture of a resin and a solvent or solvents blend gives a cloudy appearance, having been cooled from a temperature at which the mixture was clear. Commonly, a test tube of a given diameter is used and the temperature is noted when the lower end of the thermometer, placed at the bottom of the tube, disappears. Resins with cloud points below 0°C are commonly regarded as soluble and cloud points greater than 10°C indicate poor solubility/compatibility. White spirit with various aromatic contents is a widely used solvent in the determination of cloud point, but other solvents or solvents mixtures are also used. 

The critical point (Ij of the two-phase region encountered at reduced temperatures is called an upper critical solution temperature (UCST), and that of the two-phase region found at elevated temperatures is called, perversely, a lower critical solution temperature (LCST). Figure 2 is drawn assuming that the polymer in solution is monodisperse. However, if the polymer in solution is polydisperse, generally similar, but more vaguely defined, regions of phase separation occur. These are known as "cloud-point" curves. The term "cloud point" results from the visual observation of phase separation - a cloudiness in the mixture. 

The principle of this process relies on the fact that at temperatures lower than the cloud point, the catalyst remains in the aqueous phase. On heating to temperatures above the cloud point, however, the catalyst is transferred into the organic phase. Thus, the catalyst and the substrate are in the same phase and the homogeneously catalyzed reaction can proceed. As soon as the reaction is completed and the system is cooled to a temperature below the cloud point, the catalyst returns to the aqueous phase and can be recycled. 

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