Powder chemical synthesis

Chemically Synthesized Powders. Chemical synthesis provides a means of produciag powders for manufacturiag advanced ceramics. Disadvantages of chemically synthesized raw materials are expense and difficulties ia scale-up and availabihty. Additionally, ultrafine particle-size powders produced by chemical synthesis pose some unresolved processiag problems ia the areas of handling and mixing. 

Soluble impurities can be extracted by washing with deionized or distilled water foUowed by filtration (1,12,26). Powders prepared by wet chemical synthesis are often washed and filtered for purification prior to use. The dewatering (qv) process can be enhanced by pressure filtration. Organic solvents can be used to remove water-insoluble impurities and wash-water sensitive materials. 

The estimated use pattern of ethyl ether during 1990 was as follows solvents and military production of smokeless powder, 35% chemical synthesis and solvent extraction, 35% diesel starting fluid, 30% (21). 

Intermetallics also represent an ideal system for study of shock-induced solid state chemical synthesis processes. The materials are technologically important such that a large body of literature on their properties is available. Aluminides are a well known class of intermetallics, and nickel aluminides are of particular interest. Reactants of nickel and aluminum give a mixture with powders of significantly different shock impedances, which should lead to large differential particle velocities at constant pressure. Such localized motion should act to mix the reactants. The mixture also involves a low shock viscosity, deformable material, aluminum, with a harder, high shock viscosity material, nickel, which will not flow as well as the aluminum. 

Uses. Solvent chemical synthesis manufacture of smokeless powders, artificial silk, and lacquers... 

Most modern materials are formed empirically by solid-state methods. These methods generally involve more processing activity than chemical synthesis (for example, sintering of ceramic powders, modifying concrete by polymers, thermomechanical processing of alloys, layering polymeric membranes for... 

X. Dong, C. Choi, B. Kim, Chemical synthesis of Co nanoparticles by chemical vapor condensation, Powder Technol. 113 (2002) 75-79. 

CHEMICAL SYNTHESIS OF MIXED OXIDE POWDERS FOR SOLID OXIDE FUEL CELL (SOFC) ELECTROLYTE AND ELECTRODES... 

Low temperature chemical synthesis of three different mixed oxides with four-cations, LSGM, LSCM, and LSFM was investigated to produce these mixed oxides as single phase, fine powders. 

Mehmet A. Gtilgtin, Oludele O. Popoola, Waltraud M. Kriven, Chemical synthesis and characterization of calcium aluminate powders , Journal of American Creamic Society 77[2], 531-539 (1994). 

Raw stock tin (powder of 10-40 pm particles with 99.5% of the main substance) butylbromide ("pure"). The radiation chemical synthesis of dibutyltindibromide is very sensitive towards impurities in parent reactants therefore, they should be thoroughly purified. Thus, before being sent into the reactor, tin powder is washed from organic impurities with acetone, treated with diluted hydrochloric acid to remove oxide film, washed with distilled water and dried. 

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