Abstract:
The present invention relates to a stable mixture comprising surface-modified particles obtained by reacting metal or semi-metal oxide particles with at least one compound selected from silicon-containing compounds which carry one, two or three alkoxy radicals, and at least one solvent, at least one surface-active substance or a mixture thereof, to the use of these particles in systems in which they are brought into contact with at least one solvent, the mass ratio of solvent to modified particle being greater than 500, and to the use of these particles in agglomeration-deagglomeration cycles.
Abstract:
The invention relates to a method for separating at least one first material from a mixture containing said at least one first material and at least one second material. Said method comprises the following steps: (A) a suspension of the mixture containing at least one first material and at least one second material and at least one magnetic particle is produced in a suitable suspending agent; (B) the pH of the suspension obtained in step (A) is adjusted to a value at which the at least one first material and the at least one magnetic particle have opposite surface charges such that the same agglomerate; (C) the agglomerate obtained in step (B) is separated by applying a magnetic field; and (D) the agglomerate separated in step (C) is split by adjusting the pH to a value at which the at least one first material and the at least one magnetic particle have identical surface charges in order to obtain the at least one first material.
Abstract:
The present invention relates to a method for producing a layer containing at least one semiconductive metal oxide on a substrate, comprising at least the steps of: (A) producing a solution containing at least one precursor compound of the at least one metal oxide selected from the group of carboxylates from monocarboxylic, dicarbonic, or polycarboxylic acids with at least three carbon atoms or derivatives of monocarboxylic, dicarbonic, or polycarboxylic acids, alcoholates, hydroxides, semicarbazides, carbamates, hydroxamates, isocyanates, amidins, amidrazones, carbamide derivatives, hydroxylamines, oximes, urethanes, ammonia, amines, phosphines, ammonium compounds, azides of the corresponding metal and compounds thereof, in at least one solvent; (B) application of the solvent of step (A) on the substrate; and (C) thermal treatment of the substrate of step (B) at a temperature of 20 to 200 degrees Celsius, in order to transfer the at least one precursor compound in at least one semiconductive metal oxide. In the event that in step (A), electrically neutral [(OH)x(NH3)yZn]z with x, y, and z independently from one another 0.01 to 10, is used as precursor compound, said precursor compound is obtained by conversion of zinc oxide or zinc hydroxide with ammonia; a substrate, which is coated with at least one semiconductive metal oxide, obtainable by said method; the application of said substrate in electronic components; and a method for producing electronically neutral [(OH)x(NH3)yZn]z with x, y, and z independently from one another 0.01 to 10, by conversion of zinc oxide and/or zinc hydroxide with ammonia.
Abstract:
The present invention relates to a method for the production of organosols containing at least one oxide and/or oxide hydrate of metals and/or semimetals, comprising the following steps: (a) providing an aqueous solution or dispersion of at least one starting compound containing at least one metal and/or semimetal M1, (b) bringing the aqueous solution or dispersion from step (a) in contact with at least one acidic substance, (c) extracting the aqueous solution or dispersion from step (b) using at least one organic solvent or dispersion medium (L) and (d) raising the pH of the organic phase from step (c) to at least 7. The present invention additionally relates to a method for producing particles from the organosols and to the use of the organosols for producing polymer compositions or polymer coatings.
Abstract:
The invention relates to metal-nanoparticles and to methods for the production thereof in which a metallic salt solution is reduced by means of a reducing agent in the presence of the derivatised polyethylenimines or polyvinylamines. Metal salt solutions of two or more different metals can be reduced at the same time or successively. The metallic nanoparticles are obtained from two or more different metals. Metals are preferably silver, palladium and platinum. Suitable reducing agents are, for example, formic acid, formaldehyde, diethanolamine, 5-pentenic acids and sodium borohydride. Silver can be used in the form of silver oxide and/or silver nitrate, palladium can be used in the form of alkali tetrachloropalladate or palladium(ll)nitrate and platinum can be used in the form of alkali tetrachloroplatinate or tetraamine platinum(ll)nitrate.
Abstract:
The invention relates to a method for removing at least one first substance from a mixture that contains the at least one first substance and at least one second substance. Said method comprises the following steps: (A) contacting the mixture containing at least one first substance and at least one second substance with at least one surface-active substance, optionally in the presence of at least one dispersant, the surface-active substance binding to the at least one first substance, (B) optionally adding at least one dispersant to the mixture obtained in step (A) to obtain a dispersion, (C) treating the dispersion obtained in step (A) or (B) with at least one hydrophobic magnetic particle so that the at least one first substance to which the at least one surface-active substance is bound and the at least one magnetic particle are added thereto, (D) removing the addition product obtained in step (C) from the mixture by applying a magnetic field, (E) breaking down the removed addition product obtained in step (D) to obtain the at least one first substance and the at least one magnetic particle as separate entities.
Abstract:
Se refiere a una mezcla estable que comprende particulas modificadas en superficie obtenidas por la reaccion de particulas de oxido metalico seleccionados del grupo que consiste en oxido de Mn, Fe, Co, Ni y Cu, combinaciones de estos y oxidos mixtos de estos metales con al menos un metal alcalinoterreo seleccionado del grupo que consiste en Mg, Ca, Sr y Ba; con al menos un compuesto de formula general I y/o IIa, donde: R1 es hidrogeno, alquilo C1-C30, entre otros; R2 es hidrogeno, alquilo C1-C30, entre otros; m es 0, 1, 2 o 3; n es 1, 2 o 3; un solvente tal como hidrocarburos aromaticos, alcoholes, eteres, entre otros; y al menos una sustancia tensioactiva tal como surfactantes no ionicos, anionicos, entre otros. Tambien se refiere a un proceso de preparacion. Dicha mezcla de particulas funcionalizadas hidrofobicas es estable en condiciones predominantes del metodo analitico o biologico del ciclo aglomeracion-desaglomeracion, siendo utiles en procesos de separacion, purificacion del agua, purificacion de tierra contaminada con metal pesado, entre otros.