74results about How to "Lower the electrolysis temperature" patented technology

The invention provides an aluminum-lithium-samarium alloy and a fused salt electrolysis preparation method thereof. The aluminum-lithium-samarium alloy is prepared by the following steps of: heating LiCl and KCl serving as an electrolyte system to 630 DEG C for fusion in an electrolytic furnace; uniformly mixing Sm2O3 powder and AlCl3 and tabletting the mixture, adding the mixture into fused saltin the form of grains to ensure that the mass ratio of the AlCl3, LiCl to KCl is 6.2-11.0 percent to 44.5-46.9 percent to 44.5-46.9 percent, wherein the amount of the added Sm2O3 is 1 percent of the weight of the electrolytic fused salt; and taking metal molybdenum as a cathode and graphite as an anode and performing electrolysis for 2 to 6 hours to deposit the Al-Li-Sm alloy close to the cathodeof the fused salt electrolysis cell, wherein the electrolysis temperature is between 630 and 720 DEG C, the cathode current density is 6.4A / cm<2> and the anode current density is 0.5A / cm<2>. By completely using metal compounds as raw materials and adding aluminum chloride, the chlorination of samarium oxide is realized and the aluminum-lithium-samarium alloys of different components are obtained by controlling the conditions such as the proportion of the electrolytes, the electrolysis time, the temperature, the current density and the like. The alloy and the method have the advantages of simple whole process, low requirements on equipment, low energy consumption and low pollution.

The invention provides a method for preparing intermetallic aluminum-erbium or aluminum-lithium-erbium alloy by fused salt electrolysis, which is implemented in a way that: in an electrolytic furnace, metallic aluminum is use as a cathode, a graphite rod is used as an anode, and Ag / AgCl is used as a reference electrode; a mixture, which comprises 48.9 wt% of KCl, 48.9% of LiCl and 2.20% of ErCl3,is used as an electrolyte system; electrolysis is carried out at 520 DEG C; and by controlling the cathode potential at -1.4--2.1V, erbium precipitates on the solid-state aluminum cathode and diffuses to the inside of the aluminum cathode to form the aluminum-erbium alloy containing Al3Er, Al2Er and Al2Er3, or aluminum-lithium-erbium alloy containing Al-Li and Al3Er. By controlling the cathode potential, the formed strengthened phase Al3Er has high melting point and stable heat resistance, and can obviously enhance the strength of the aluminum-erbium or aluminum-lithium-erbium alloy. The invention overcomes the actual state that the composition of the aluminum-erbium or aluminum-lithium-erbium alloy prepared by the fused salt electrolysis process can not be controlled.

The invention discloses a preparation method of a praseodymium-iron alloy. The preparation method comprises the following steps: in equipment for electrolyzing a praseodymium-iron intermediate alloy, under a fluoride molten salt electrolyte system of praseodymium fluoride and lithium fluoride, direct current is introduced to electrolyze praseodymium oxide serving as an electrolysis raw material to obtain the praseodymium-iron intermediate alloy; and the praseodymium-iron intermediate alloy and iron serve as raw materials, the praseodymium-iron alloy is prepared through a melting and blending method, and the melting and blending process is carried out under the vacuum condition. According to the preparation method of the praseodymium-iron alloy, the praseodymium-iron alloy obtained after the praseodymium-iron intermediate alloy obtained through molten salt electrolysis is subjected to vacuum melting and blending is accurate in component control, due to the fact that melting is conducted under vacuum, the burning loss of rare earth is small, the yield is high, the praseodymium-iron alloy is uniform in component, small in segregation and low in impurity content, and when the praseodymium-iron alloy is applied to rare earth steel, the yield of rare earth is high, and the effect is remarkable.

Belonging to the technical field of aluminium electrolysis, the invention specifically relates to a method for improving an alumina dissolution rate in an aluminium electrolysis process. The key points lie in that, fluorinated alumina, high igloss alumina or additive-containing alumina is added into an electrolyzer as an electrolysis raw material, and hydrogen fluoride, water vapour or carbon dioxide that are escaped from an alumina dissolution process can play a stirring role, so that the dissolution rate of alumina in the electrolyzer can be greatly enhanced. With extremely simple process and low cost, the method provided in the invention can effectively improve the dissolution rate of alumina, enhance the current efficiency of the electrolysis process and reduce the electrolysis temperature, thus reducing industry energy consumption and saving energy sources, as well as being able to be widely promoted and applied in industrial production.

The invention relates to a low-temperature aluminum electrolysis process and electrolyte. The electrolyte consists of Na3AlF6, K3AlF6, Al2O3, AlF3 and LiF; and the electrolysis temperature is between 850 and 910 DEG C, the coefficient of an anode effect is smaller than 0.1 time / tank day, and the anode current density is 0.5 to 1.2 A / cm2. The primary crystal temperature of the electrolyte adoptingthe component formula is low and changes comparatively slowly along with the changes of the components in favor of solving the problems of uneven tank bottom current, unstable tank voltage and the like caused by sharp raising of the primary crystal temperature of a melt and cathode crusting due to directional migration of Na+ and cathode enrichment. Besides, The K3AlF6 in the electrolyte can effectively increase the capability of the melt for dissolving the aluminum oxide, and solve the problem of deposition of the aluminum oxide at the bottom of a tank. Because the electrolysis temperature is lower, the heat loss of an electrolytic tank can be greatly reduced, and the energy-saving current efficiency is high. The low-temperature aluminum electrolysis process is simple and is easy to operate, the electrolyte has reasonable components, and the low-temperature aluminum electrolysis process can effectively reduce the aluminum electrolysis temperature, inhibit the cathode crusting in the process of aluminum electrolysis, improve the current efficiency of the aluminum electrolysis and reduce the energy consumption of the aluminum electrolysis, is suitable for industrial production, andcan replace the conventional aluminum electrolysis process.