Impregnation trickle

The trickle impregnation process is a related process to thermoset plastic casting, potting, and encapsulation where it also uses a low viscosity liquid reactive plastic to provide the trickle impregnation. As an example, the catalyzed plastic drips on to an electrical transformer coil. Capillary action draws the liquid into its openings at a rate slow enough to enable air to escape as it is displaced by the liquid. When fully impregnated, the part is exposed to heat to cure the plastic. 

For these studies the NiX precursor catalyst has been impregnated with molten lithium acetate. The catalyst displayed remarkably good selectivity to octenes. A typical set of results is shown in Fig. 18, where the reactant and product concentrations are given as a function of contact time, t. The results indicate that isomerization of 1-butene to an equilibrium mixture with 2-butenes (cis and trans) occurs rapidly, followed by the slower dimerization of butenes to octenes. The reaction was carried out under mixed phase conditions with the 1-butene reactant in the gas phase and the octene products in the liquid phase (trickle-bed reactor). Under the conditions the reaction rate was found to be mass-transfer controlled. 

The chemical resistance of an organic material depends to a very large extent on the molecular weight of the polymer concerned. When optimally cured, po-ly(ester-imide) wire enamels are resistant to the styrene used in impregnating and trickle resins. Optimum curing is dependent, when all the other parameters of the enameling machine are held constant, on the enameling speed of the wire. 

Ambulance men drilling in the standard British gas mask, the P Helmet , July 1916. The bag of flannel made the face sweat and the chemical which impregnated it then ran, stinging the eyes and trickling down the neck. In addition to the discomfort, the masks often leaked, the eyepieces cracked, and a lethal amount of carbon dioxide could build up inside the helmet. 

In Chapter 2 we discussed a number of studies with three-phase catalytic membrane reactors. In these reactors the catalyst is impregnated within the membrane, which serves as a contactor between the gas phase (B) and liquid phase reactants (A), and the catalyst that resides within the membrane pores. When gas/liquid reactions occur in conventional (packed, -trickle or fluidized-bed) multiphase catalytic reactors the solid catalyst is wetted by a liquid film as a result, the gas, before reaching the catalyst particle surface or pore, has to diffuse through the liquid layer, which acts as an additional mass transfer resistance between the gas and the solid. In the case of a catalytic membrane reactor, as shown schematically in Fig. 5.16, the active membrane pores are filled simultaneously with the liquid and gas reactants, ensuring an effective contact between the three phases (gas/ liquid, and catalyst). One of the earliest studies of this type of reactor was reported by Akyurtlu et al [5.58], who developed a semi-analytical model coupling analytical results with a numerical solution for this type of reactor. Harold and coworkers (Harold and Ng... 

NiX precursor catalyst impregnated with molten lithium acetate Trickle-bed reactor, reactant in gas phase and the products in the liquid phase Octenes 230 s OQ... 

The global glucose oxidation rate in a low mass velocity trickle bed was found by Tsukamoto, Morita and Okada [78] to be higher than for a liquid full reactor in which the liquid was presaturated with oxygen. The catalyst was an activated charcoal impregnated with immobilized enzymes. The charcoal was 0.055 and 0.011 cm in size. The reactor was 2.1 cm I.D. and 27 cm long. 

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