Cloud point test

Aniline and mixed aniline point (DIN 51 775 modified). It is similar to the cloud point test except that the solvent is aniline, a very polar liquid. The aniline point is defined as the temperature at which a mixture of equal parts of aniline and the resin show the beginning of phase separation (i.e. the onset of clouding). Phase separation for aromatic resins occurs between I5°C and below zero for resins with intermediate aromaticity, it lies between 30 and 50°C and for non-aromatic resins, it is 50 to 100°C. Sometimes the mixed aniline point is used. It is similar to the aniline point except that the solvent is a mixture of one part of aniline and one part of w-heptane. The problem of both procedures is that precipitation of resins can be produced before the cloud is generated. 

A more quantitative estimation of compatibility can be obtained with the solvent cloud point test. The solvent cloud point is based on the idea that resins will be compatible with elastomers of similar chemical nature. Thus aliphatic resins will be effective tackifiers for aliphatic elastomers, such as natural rubber, while aromatic solvents are needed for aromatic elastomers, such as SBR. Solvent cloud point tests are carried out in three solvent systems which represent aliphatic, aromatic, or polar systems [16j ... 

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. 

Boemer Number, Foreign Fats in Lard (Cb 5-40) estimates the presence of tallows and similar fats, based on differences in melting points of foreign glycerides and fatty acids as compared with pure pork fat. Cloud Point Test (Cc 6-25) determines the temperature at which a cloud first forms in cooling a sample of melted fat to the first stage of crystallization Cold Test (Cc 11-53) measures the relative resistance of a sample to crystallize at an established temperature in terms of time. The 5.5-hr test at 0°C is used as an index of stearin removal in the winterization of salad oils. 

In the simple cloud point test method (ASTM D-2500), the sample is first heated to a temperature above the expected cloud point and then cooled at a specified rate and examined periodically. The temperature at which haziness is first observed at the bottom of the test jar is recorded as the cloud point. 

The oil must pass the solid paraffin test at 0°C (this is essentially a cloud point test) by remaining clear at this temperature. This is established in the dewaxing step. 

Cloud Point Test (Cc 6-25) determines the temperature at which a cloud first forms in a sample of melted fat in the first stage of crystallization. 

Proceed as iit the cloud point test with the difference that the thermometer bulb is just completely immersed in the oil, instead of touching the bottom (Figure 4.3). 

Report the temperature recorded in 8.7 as the Cloud Point, Test Method D 2500. 

Ethoxylated materials exhibit water solubility which is lower, rather than higher, at higher temperature (43). This is the basis of the cloud point test, an identity check for nonionic surfactants which reflects the extent of ethoxylation (44). A solution of the surfactant is warmed until it becomes cloudy, and the temperature recorded. For a family of materials, cloud point is directly proportional to extent of ethoxylation. Usually, the cloud point is not much affected by concentration in the 1-10% range. Highly ethoxylated materials (EO > 75%) often do not have a cloud point below the boiling point of water, although there may be a measurable cloud point in 1 M sodium chloride solution. 

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). 

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. 

A melamine laminating resin used to saturate the print and overlay papers of a typical decorative laminate might contain two moles of formaldehyde for each mole of melamine. In order to inhibit crystallization of methylo1 melamines, the reaction is continued until about one-fourth of the reaction product has been converted to low molecular weight polymer. A simple deterrnination of free formaldehyde may be used to foUow the first stage of the reaction, and the build-up of polymer in the reaction mixture may be followed by cloud-point dilution or viscosity tests. 

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. 

Certain properties of a liquid fuel are measured routinely in a laboratory for characterization purposes. Besides density and viscosity, these properties include the pour point, the cloud point, and the flash point. Standard ASTM (American Society for Testing Materials) procedures are available for their determination. 

Cloud Point Measurements Cloud points were recorded by the visual observation of aqueous solutions containing 1% W/V surfactant. The measurement defines the temperature at which the system under test shows a characteristic transitional change from a clear solution to an opalescent or cloudy state. All cloud points were recorded in both ascending and descending temperature cycles to ensure data confidence. The influence of salt and/or oils on the cloud point were systematically evaluated. 

If shearing has destroyed the loosely formed wax lattice network of gelled crude oil so that the oil flows below its natural pour point, heating can restore the oil to its original pour point. By heating the crude oil to temperatures 20°F to 30°F (11.1 °C to 16.7°C) above the cloud point, waxes can be melted, solubilized and redistributed into the oil. When the pour point is then determined for this heated oil, the result obtained may be higher than the result obtained for the same oil which was not heated prior to pour point testing. All wax must be melted and solubilized into... 

The temperature at which a cloud is first observed at the bottom of the test jar is recorded as the cloud point. 

The simulated filter plugging point (SFPP) was developed in Europe as a supplement to the CFPP test. Work initiated in 1982 by the Coordinating European Council (CEC) demonstrated that the CFPP can become unreliable whenever the CFPP is lowered more than 50°F (10°C) below the cloud point of the fuel. The SFPP was developed to better predict the operability of fuel at temperatures >50 °F (>10°C) below the fuel cloud point. 

Place an aluminum disk into the cap of the bottom section of the test cylinder. Pour 40 mL of test fuel into the bottom section of the test cylinder. The fuel should be added at room temperature or at least 10°F (5.5°C) above the cloud point of the fuel. 

Cloud Point This is the temperature at which a cloud or haze of wax crystals appears when a fuel or lubricant is cooled under standard test conditions. 

The observation of CST with practical precision is usually very simple. The two liquids are placed in a test tube and are stirred with a thermometer while heating or cooling until the liquids just mix (while heating) or just cloud (on cooling). Determinations of the cloud point are usually more precise than determinations of the temperature of disappearance of two phases. There is very little risk of subcooling a liquid mixture below the CST, and having it remain homogeneous. When the upper layer becomes small before it disappears, more of the major component of the upper layer is added, and the observation is repeated until the interface disappears near the middle of the system. This is necessary in order to... 

The objective of this test was to assess the wax deposition tendency of Troll crude in a cool subsea flowline. The equipment consists of a thermostatted stirred vessel from which crude oil is circulated by a gear pump through a thermostatically controlled stainless steel capillary. Tne temperature in the vessel was maintained at 6S°C and the capillary tube was held at a constant temperature below the cloud point. 

Dne after another, the components Tests Viscosity (mPas) 330 Cloud point <-5C of B are added to A. 

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