Patent ID: 8936710
Filing Date: 2015-01-20
Classification: C01F,C25C

Abstract:
1. A method for preparing a low-molecular-ratio cryolite for aluminium electrolytic industry, which consists of potassium cryolite and sodium cryolite with a mole ratio of 1:1˜1:3, wherein the molecular formula of the potassium cryolite is mKF.AIF 3 , m=1˜1.5; the molecular formula of the sodium cryolite is nNaF.AIF 3 , n=1˜1.5, the method including the following steps: A) putting aluminium into a reactor, injecting an inert gas to the reactor after vacuumizing, heating the reactor to a temperature of between 700 and 850 DEG C, adding potassium fluotitanate or a mixture of potassium fluotitanate and potassium fluoborate in the reactor and stirring for 4 to 6 hours, pumping the superstratum melt liquid to obtain potassium cryolite; B) putting aluminium into another reactor, injecting an inert gas to the reactor after vacuumizing, heating the reactor to a temperature of between 700 and 850 DEG C., adding sodium fluotitanate or, alternatively, sodium fluoborate two in the reactor and stirring for 4 to 6 hours, pumping the superstratum melt liquid to obtain sodium cryolite; and C) mixing the obtained potassium cryolite with the obtained sodium cryolite in a mole ratio of 1:1˜1:3.