摘要:
This invention relates to a partially dehydrated hydrotalcite obtained by heat-treating a hydrotalcite under a specific condition so that its weight is reduced by 1.5 to 5%, which is capable of imparting improved thermoresistance to a synthetic resin.
摘要:
The invention relates to a method for producing a complex fluoroaluminate, wherein the fluoroaluminate is obtained by spray drying a suspension containing the fluoroaluminate, to the fluoroaluminate produced according to this method and to the use of said fluoroaluminate. The invention also relates to the utilization of spray drying for controlling the macroscopic structure of a fluoroaluminate and the utilization of a polyalkyleneglycol for identical purposes.
摘要:
Verfahren zur Herstellung von kristallinem Kryolith eines moleren Na:Al-Verhältnisaes von 2.9:1 bis 3,0:1 durch Reaktion wäßriger Lösungen von Alumirdumfluorid mit der stöchiometrischen oder überatöchiometrischen Menge Natriumfluorid in wäßriger Lösung unter Erhitzen in Anwesenheit von Kryolith-Impfkristellen. Das Natriumfluorid wird in Mengen von 3,0 bis 3,6 Mol Na pro Mol Al angewendet, die AIFrKonzentrationen betragen zwischen 15 bis 250 g l, die NaF-Konzentrationen 30 bis 42 g /l, die Reaktionstemperaturen zwischen 85-100°C, die Reaktionszeit 0,5 bis 3 Stunden und die pH-Werte im Reaktionsgemisch zwischen 5 und 8. Erhalten wird ein Endprodukt mit Haftwassergehalten von etwa 6% und darunter.
摘要:
A method for preparing zirconium boride and synchronously preparing a cryolite is provided which inc ludes the following step s: Step A: placing aluminum in a reactor , heating the reactor to 700-850 degrees cent igrade, and adding the mixture of fluorozirconate and fluoborate; and Step B: stirring the reactants for 4-6 hours and extracting the upper molten liquid to obt ain a cryolite, wherein the lower subst ance is zirconium boride. The disclosure has the following beneficial ef fects: the new zirconium boride preparation method provided herein is simple in preparation flow and the device used, short in prep aration pe riod and high in reaction ef ficiency, the prepared zirconium boride with m any contact angles has a large specific surface area and contains a controllable amount of aluminum.