Heavy paraffinic waxes

A set of kinetic parameters was produced using the experimental data obtained on K-hexadecane. The reaction rates of all the acyclic paraffins can therefore be calculated. This Section VI.C will compare the calculation results with the experimental data obtained on heavy feedstocks. The experiments conducted on heavy paraffinic waxes can be used to test the extrapolation capacities with respect to the number of carbon atoms (from nC 16 to C20- C33). 

On the other hand, intermediate paraffin distillates contain paraffin waxes and waxes intermediate in properties between paraffin and microwaxes. Thus, the solvent dewaxing process produces three different slack waxes depending on whether light, intermediate, or heavy paraffin distillate is processed. The slack wax from heavy paraffin distillate may be sold as dark raw wax, the wax from intermediate paraffin distillate as pale raw wax. The latter is treated with lye and clay to remove odor and improve color. 

One of the most important, and perhaps the best studied, applications of three-phase fluidization is for the hydrogenation of carbon monoxide by the Fischer-Tropsch (F-T) process in the liquid phase. In this process, synthesis gas of relatively low hydrogen to carbon monoxide ratio (0.6 0.7) is bubbled through a slurry of precipitated catalyst suspended in a heavy oil medium. The F-T synthesis forms saturated and unsaturated hydrocarbon compounds ranging from methane to high-melting paraffin waxes (MW > 20,000) via the following two-step reaction ... 

The paper used to form the tubes that contain the constituents of the various types of Dynamites are heavily impregnated with paraffin wax. After the tubes are filled and crimped, they are dipped into molten paraffin wax. This technique is used to seal the Dynamite sticks against moisture (Ref 20). Similarly a heavy coating of paraffin wax is used to protect commercial highway emergency flares from water and moisture... 

Barriers can conveniently be made of strips of plate glass, not less than 1 cm. wide and a few mm. thick, so as to be heavy. They must be coated, after cleaning, with a good hard paraffin wax. 

This method of producing wax fractions is much faster and more convenient than sweating and results in a much more complete separation of the various fractions. Furthermore, recrystallization can also be applied to the microcrystalline waxes obtained from intermediate and heavy paraffin distillates, which cannot be sweated. Indeed, the microcrystalline waxes have higher melting points and differ in their properties from the paraffin waxes obtained from light paraffin distillates, and thus, wax recrystallization has made new kinds of waxes available. 

The variety of substances used as additives in polymers is considerable. For example, the fillers may include china clay, various forms of calcium carbonate, talc, silicas (diatomaceous silica), silicates, carbon black, etc. The impact modifiers typically include other polymers. Plasticizers include certain polymers with low (oligomers), dialkyl phthalates, dialkyl sebacates, chlorinated paraffin waxes, liquid paraffinic fractions, oil extracts, etc. Heat stabilizers include heavy metals salts such as basic lead carbonate, basic lead sulfate, dibasic lead phosphite (also acting as a light stabilizer), dibasic lead phthalate, stearates, ricinoleates, palmitates and octanoates of cadmium and barium, epoxide resins and oils, amines, diphenylurea, 2-phenylindole, aminocrotonates. The antioxidants include tris-nonyl phenyl phosphite, 2,6-di-ferf-butyl-p-cresol (BHT), octadecyl-3,5-di-terf-butyl-4-hydroxyhydrocinnamate, etc. The UV stabilizers include modified benzophenones and benzotriazoles. Processing lubricants include calcium stearate, stearic acid, lead stearate, various wax derivatives, glyceryl esters and long-chain acids. Fire retardants include antimony oxide, some pyrophosphates, etc. 

It is evident that the above approach was followed to arrive at a high selectivity towards middle distillates, the prerequisite being a second stage which can convert the heavy wax fraction in the HPS effluent very selectively into middle distillates, the Heavy Paraffin Conversion (HPC) stage (see Fig. 2). In the HPC the waxy product of the HPS is hydro-isomerized and hydrocracked to give the maximum yield of middle distillates. 

Reid98 recently employed high pressures while attempting the oxidation of heavy hydrocarbons but does not give detailed data. Extensive investigations on the oxidation of paraffin wax under high pressures have been made by Fischer.90 This work showed iron and copper salts to be the best catalysts and yields as high as 74 per cent of fatty acids were obtained. 

The strongest films are formed under the most acidic conditions. Finally, the films least able to relax under reduced surface stress conditions were observed to form the most stable emulsions. They also found that components other than asphaltenes, such as alkanes (paraffin waxes), resins, and aged interfacially active components of relatively high H/C ratio (1 5), can also contribute to the stabilization of water-in-crude oil emulsions. They concluded that the state of solvation of asphaltenes in the oil phase plays an important role in their ability to stabilize emulsions, which may explain the indirect action of resins on emulsion stability. The temperature is also an important factor when it comes to the stability of crude oil emulsions, especially true when the wax content is relatively high. The most important factor influencing the water-in-crude oil emulsion stability at low temperature is the interaction at the water-oil interface between wax crystals and the heavy fractions of the crude. 

Waxes Waxes are an additional class of materials used to improve rubber ozone protection primarily under static conditions. Waxes used in elastomeric formulations fall into two categories microcrystalline and paraffin. Microcrystalline wax has a melting point in the range of 55-100 C and is extracted from residual heavy lube stock of refined petroleum. Paraffin wax has melting points in the range of 35-75°C and is obtained from the light lube distillate of crude oil. 

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