Inorganic synthesis precipitation

Figure 1. Schematic illustration of hollow polyelectrolyte capsule formation (a-c) followed by the selective inorganic synthesis inside (d-e). a-b layer-by-layer precipitation of poly(styrene sulfonate), poly(allylamine hydrochloride) monolayers b-c dissolution of template core c-d loading of polyelectrolyte capsules with corresponding anions d-e precipitation of inorganic material from... 

Figure 2 Evolution of the neutron scattering intensities with time. Only spherical micelles of P123 block copolymer are present in the synthesis mixture within the first few minutes of the reaction (300 s), during the hydrolysis of the silica precursor. Then, hybrid organic-inorganic cylindrical micelles are detected (300-1400 s). The SBA-15 hexagonal phase is formed when the precipitation occurs, after 1400 s.

Alkali ions (salts) influence the formation of the precursor gel for most of the synthetic zeolites (3,34,39,40). Na+ ions were shown to enhance in various ways the nucleation process (structure-directing role) (40-42), the subsequent precipitation and crystallization of the zeolite (salting-out effect) (JO and the final size and morphology of the crystallites (34,43). Informations on the various roles played by the inorganic (alkali) cations in synthesis of ZSM-5, such as reported in some recent publications (7,8,10,14,17,29,30,44,45) remain fragmentary, sometines contradictory and essentially qualitative. 

Pigment synthesis follows the typical route to azo pigment lakes the aniline derivative or the aniline sulfonic acid is diazotized with sodium nitrite in an acidic medium (hydrochloric acid), followed by coupling on the Naphthol AS derivative, which is initially dissolved in an alkaline solution and then precipitated by adding inorganic or acetic acid. If a Naphthol AS sulfonic acid is used as a coupling component, it must be neutralized with alkali for dissolution and coupled directly. 

Chapter 11 - In work the synthesis technology of zinccontaining polymer - inorganic composite on the basis of products of secondary raw material processing at joint precipitating with carbamide and formaldehyde (ZnCFO) is described. 

The most important applications of hydrogen sulfide involve the production of sodium sulfide and other inorganic sulfides. Hydrogen sulfide obtained as a by-product often is converted into sulfuric acid. It also is used in organic synthesis to make thiols or mercaptans. Other applications are in metallurgy for extracting nickel, copper, and cobalt as sulfides from their minerals and in classical qualitative analytical methods for precipitation of many metals (see Reactions). It also is used in producing heavy water for nuclear reactors. 

The entire spectrum of tools in synthetic inorganic chemistry, including high temperature methods, precipitation, solvothermal synthesis, sol-gel chemistry, chemical vapor deposition (CVD), and soft matter techniques adopted in part from organo-metallic chemistry, have been applied to synthesize the active mass of catalysts. Table 4.2.1 summarizes basic techniques. The preparation methods differ whether... 

The primary thrust of the material in this chapter will be to indicate to researchers not already familiar with the details of superacid chemistry that, for the synthesis of many inorganic fluorides and other compounds containing fluorine, a favourable reaction medium can frequently be found by careful selection of an appropriate superacid, by deliberate control of the acidity or basicity of that medium and by use of suitable redox and other reactants and precipitants. 

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