A method for preparing aluminum-silicon alloy by mixing aluminum-containing minerals and fly ash by chlorination and low-temperature electrolysis

Abstract

The invention provides a method for preparing aluminum silicon alloy through mixed chlorination and low-temperature electrolysis of aluminum-containing mineral and fly ash. According to the method, a mixture of bauxite and fly ash with different reaction activities is used as a raw material, the catalytic effect of a chlorination product of the bauxite on the chlorination process of the fly ash enables that the chlorination temperature of the fly ash is reduced, the reaction can be continuously performed in a fluidized state, and the reaction efficiency is improved. Meanwhile, since the aluminum-containing mineral and the fly ash have different chemical compositions, the adjustment and control on the composition of the chlorination product can be realized by adjusting the proportion of the mixed materials, the processes such as moisture absorption can be effectively reduced, and the cost is saved. The method can be used for realizing effective separation of iron impurity in the chlorination product in low-temperature ironic liquid, and meanwhile also obtaining an elementary substance iron byproduct. Electrolysis is performed in the ionic liquid within the temperature range of 40-100 DEG C to prepare aluminum silicon alloy with certain composition after purification, so that the heat loss is obviously reduced and the current efficiency is improved.

Description

Technical field [0001] The invention relates to a method for preparing aluminum-silicon alloy by mixed chlorination of aluminum-containing minerals and fly ash and low-temperature electrolysis, and belongs to the technical field of electrochemical metallurgy. Background technique [0002] Anhydrous aluminum trichloride is currently mainly used as a catalyst for organic synthesis, and the market demand is not large. Therefore, most anhydrous aluminum trichloride manufacturers use metallic aluminum as raw materials to preheat the processed high-purity aluminum After that, it is added into a closed chlorination reaction furnace, and chlorine gas reacts with metallic aluminum at 800-900°C to produce anhydrous aluminum trichloride. It is precisely because this method uses high-purity aluminum as the raw material to produce anhydrous aluminum chloride at a relatively high cost, which greatly limits the application of anhydrous aluminum chloride. The proposal of ionic liquid system low...

AI Technical Summary

Problems solved by technology

However, fly ash is an aluminum-containing silicate calcined at high temperature. There are two obvious defects in the preparation of anhydrous aluminum chloride by chlorination of fly ash as raw material: first, the crystal phase of aluminum, silicon and other substances is relatively stable, and the chlorination temperature is relatively stable. It is 50-100°C higher than industrial alumina or bauxite, that is, fly ash can be chlorinated better at 800-900°C. At this time, calcium and magnesium chloride produced in the system are in a molten state, which directly leads to the bonding of reaction materials. , fluidized bed loss; secondly, the alumina content in fly ash is 20-35% lower, and the silicon oxide content is 40-56% higher. The material flow in the chlorination process aimed at producing anhydrous aluminum chloride is larger, and the process Longer and costs significantly more

However, this method has high requirements on the taste of aluminum ore resources, the process is very complicated, energy consumption is large, and production costs are high. These factors have restricted the development of my country's aluminum industry to a certain extent.