Process for preparing chrome acid anhydride from ferrochrome through acid soluble electrolytic method

Abstract

The invention relates to a process for preparing chrome acid anhydride from ferrochrome through an acid soluble electrolytic method. Ferrochrome is ground into fine powder and placed into a reaction still, acid is added to dissolve the ferrochrome, special substances are added for reaction with heating, trivalent chromium and ferrous ions are separated, then a trivalent chromium solution is placed into an electrolytic cell, the trivalent chromium is completely converted into hexavalent chromium through electrolytic oxidation, and chrome acid anhydride products are prepared. Through the process, series chromium compounds including dichromate, chromium sulfate, chromic chloride, chromic oxide, chromic hydroxide, a chrome tanning agent, chromium picolinate and chromium nicotinate, iron series pigment including ferrous oxalate, iron blue and ferbam, new materials including silicon and carbon, and new energy, namely hydrogen, are prepared simultaneously. The process is advanced, short in technological process, capable of saving energy and environmentally friendly, the produced products are good in quality, high in value and good in benefit, and the sustainable development of the chrome salt industry can be better prompted.

Description

technical field [0001] The invention relates to a process for preparing chromic anhydride by ferrochrome acid-dissolving electrolysis, which belongs to the chemical industry for producing chromic anhydride, dichromate, trivalent chromium salt, iron-based pigments, new silicon materials and new energy by using the metallurgical product ferrochrome as raw material The field of new material technology. Background technique [0002] Chromium salt products play an important role in economic development and are widely used in electroplating, leather, wood preservation, printing and dyeing, ceramics, pigments, plastic products, inks, coatings, paints, biological products and other fields. With the acceleration of international economic integration, the competition of enterprises is becoming increasingly fierce. To survive and develop in the fierce international competition, enterprises must adjust and optimize the industrial structure, change the mode of economic development, accel...

AI Technical Summary

Problems solved by technology

[0004] At present, chromium salt enterprises at home and abroad are completely using the method of roasting with calcium or less calcium to produce chromate and then produce chromic anhydride, and the chromium salt production technology that is being tested in China: ferrochrome alkali dissolution oxidation to produce sodium chromate, pneumatic fluidization tower The continuous liquid phase oxidation method of chromate, potassium or sodium sub-molten salt liquid phase oxidation method of chromate requires high temperature and high pressure, and the amount of sodium or potassium alkali is too large, so there is a big safety hazard, and the cost of the reaction vessel is high and difficult to manufacture. The production cost is high, and the production process produces a large amount of iron oxide and silicon dioxide containing hexavalent chromium. It is difficult to treat the chromium slag, and the profit is low or loss-making. It is difficult to apply in industrial production.

[0005] Sichuan Yinhe Chemical Co., Ltd. invented "a production method of high-quality red alum sodium", application number: 201310113700.7, publication number: CN 103193271.A, publication date: 2013.07.10. Alkali has extremely high requirements on container material, design, and reaction conditions. The cost of the reaction container is high, the damage to the container is great during the production process, and it is easy to cause a large safety hazard.

Due to the high production cost, there is only a single product, sodium dichromate, and at the same time, the toxic chromium slag is difficult to deal with, and it is difficult to industrialize production

"Method for preparing sodium dichromate dihydrate by ion membrane electrolysis" invented by Salt Lake Institute of Chinese Academy of Sciences, application number: 200910001674.2, publication number: CN101481802.A, publication date 2009.07.15, this method uses sodium chromate as the anode Liquid, sodium hydroxide is used as the dihydrate sodium dichromate of electrolytic solution preparation, and PH value is strong alkaline, and product does not meet quality standard requirement, cannot industrialized production

[0006] Since the original chromate production adopts calcium roasting and calcium-free roasting methods, a large amount of toxic dust, waste gas, waste water, and waste residue are produced, causing great harm to humans and the environment. Therefore, there is an urgent need for a high-tech, advanced and applicable chromium salt production. method