Abstract:
The present invention concerns a method for processing titanomagnetite ore materials, said method comprising the steps of: - reacting a titanomagnetite raw material with a fluorinating agent to obtain a fluorinated product, - heat treating said fluorinated product to obtain a sublimate product containing ammonium fluorotitanate compound(s), ammonium fluorosilicate compound(s) and the excess of the fluorinating agent, and a first solid residue, - cooling down said sublimate product to a first de-sublimation temperature to obtain a first de-sublimated product containing ammonium fluorotitanate compound(s) and a first gaseous residue, - cooling down said first gaseous residue to a second de-sublimation temperature lower than said first de-sublimation temperature to obtain a second de-sublimated product containing ammonium fluorosilicate compound(s), and a second gaseous residue.
Abstract:
The present disclosure relates to a vapor phase process for producing a substantially anatase-free titanium dioxide pigment comprising reacting a vaporous titanium dioxide precursor and an oxygen containing gas in a reactor; and introducing a mixture of liquid silicon halide and liquid titanium dioxide precursor into the reactor at a point downstream of the addition of the vaporous titanium dioxide precursor, and the oxygen containing gas, and at a process temperature of about 1200 °C to about 1600 °C to produce titanium dioxide particles that are substantially encapsulated in silicon dioxide.
Abstract:
Die Erfindung betrifft die Herstellung von Titandioxid durch Oxidation von Titantetrachlorid in einem mehrstufigen Verfahren, wobei in der ersten Stufe flüssiges Titantetrachlorid und in einer zweiten Stufe gasförmiges Titantetrachlorid eingesetzt wird. In der ersten Stufe beträgt das Molverhältnis O 2 : TiCl 4 mehr als 1. Die in der ersten Stufe eingesetzte Menge flüssigen Titantetrachlorids beträgt vorzugsweise nicht mehr als 20% der Gesamtmenge. Das erfindungsgemäße Verfahren ist energieeffizient und führt zu geringeren Titandioxidpartikelgrößen.
Abstract:
The disclosure provides a process for recycling ore in the chloride process, without the build-up of silica-containing gangue in the chlorination reactor.
Abstract:
Die Erfindung betrifft die Herstellung von Titandioxid durch Oxidation von Titantetrachlorid in einem mehrstufigen Verfahren, wobei sowohl Sauerstoff wie Titantetrachlorid in mehreren Stufen dosiert werden. In der ersten Stufe wird gasförmiges TiCI 4 in einen vorerhitzten sauerstoffhaltigen Gasstrom stöchiometrisch oder überstöchiometrisch eingeleitet, um eine TiO 2 enthaltende Gassuspension zu erzeugen. In der zweiten oder weiteren Stufen wird flüssiges TiCI 4 und sauerstoffhaltiges Gas in die TiO 2 enthaltende Gassuspension eingeleitet, um weiteres TiO 2 zu erzeugen. In einer Ausführung der Erfindung werden in der zweiten oder weiteren Stufen TiCI 4 und sauerstoffhaltiges Gas mit einer Temperatur unter etwa 50 °C zugegeben. Die Erfindung ermöglicht gegenüber bekannten Verfahren aus dem Stand der Technik deutliche Energieeinsparungen.
Abstract:
In order to provide nanoscale metal oxide fine particles having an excellent dispersibility in an organic solvent, metal oxide fine particles are obtained by heating and reacting metal halide and metal alkoxide in the presence of phosphine oxide. The heating is performed by microwave irradiation.
Abstract:
La présente invention vise la synthèse de nanoparticules par pyrolyse laser. A cet effet, un précurseur interagit avec un faisceau laser (LAS) dans un réacteur de pyrolyse (REAC) pour produire des nanoparticules (nP). Caractérisé en ce que le précurseur est d' abord en phase liquide et est ensuite porté en phase vapeur, et en ce que le débit du précurseur est contrôlé en phase liquide.
Abstract:
The disclosure relates to a process for making titanium dioxide, comprising: reacting titanium tetrachloride with oxygen by contacting the titanium tetrachloride with the oxygen in a vapor phase reactor under mixing conditions and at an elevated temperature to form a gaseous product stream containing titanium dioxide; separating the titanium dioxide from the gaseous product stream to form a process stream; analyzing the process stream to detect a concentration of titanium tetrachloride in the process stream; comparing the concentration of titanium tetrachloride detected in the process stream to an aim point concentration; and modifying the oxidation conditions to restore or maintain the concentration of titanium tetrachloride in the process stream at the aim point. In one embodiment, the process further comprises contacting the gaseous product stream with silicon tetrachloride under mixing conditions and at an elevated temperature to at least partially encapsulate the titanium dioxide with a silicon-containing compound and separating the at least partially encapsulated titanium dioxide from the gaseous product stream and analyzing the process stream to detect a concentration silicon tetrachloride for comparison to a silicon tetrachloride aim point concentration so that the conditions for silicon tetrachloride contacting can be modified to restore or maintain the concentration of silicon tetrachloride in the process stream.
Abstract:
The invention is a method for producing a metal oxide catalyst useful for purifying exhaust gases and waste gases from combustion processes. The method comprises reacting a titanium dioxide precursor, a vanadium oxide precursor, and a tungsten oxide precursor in the presence of oxygen at a temperature of at least 1000°C.