Rough extraction method for cordierite type waste automobile tail gas three-way catalyst

Abstract

The invention discloses a rough extraction method for a cordierite type waste automobile tail gas three-way catalyst. According to the method, under the specific condition of a proper amount of HF liquid, the SiO2-Al2O3 bond in the waste automobile tail gas three-way catalyst is opened, gamma-Al2O3 and part of cordierite structures (2MgO.2Al2O3.5SiO2) are destroyed, and part of Si in the waste automobile tail gas three-way catalyst is separated in a differentiation manner; then, the waste automobile tail gas three-way catalyst is further treated under the specific condition through the pressurizing alkaline leaching technology, part of Al, Si and the like in the waste automobile tail gas three-way catalyst are selectively dissolved out, finally, a platinum group metal enriched body is obtained, a sodium aluminate solution obtained through pressurizing alkaline leaching is subjected to enhanced decomposition through microwaves, hydrated alumina is obtained, and recycling of aluminum in the waste automobile tail gas three-way catalyst is achieved.

Description

Technical field [0001] The invention belongs to the field of comprehensive recycling and utilization of resource regeneration, and specifically relates to a method for crude extraction of a cordierite type waste automobile tail gas three-way catalyst with high silicon and high aluminum content. Background technique [0002] Platinum group metals are widely used in automotive, chemical, aerospace, electronics, finance, petroleum, jewelry and other industries due to their unique physical and chemical properties and good financial characteristics. They are the core materials of modern defense and military technology and the strategic reserves for national defense construction. Supplies. my country's platinum group metals are short of primary resources and low grade, about 0.5-0.6g / t, with reserves of 324 tons, accounting for only 0.39% of the global platinum group metal resources. The domestic platinum group metal annual output is only 10t, but the platinum group metal is currently ...

AI Technical Summary

Problems solved by technology

However, practice has proved that the current recycling process cannot meet the requirements of the society and the market for resource recovery, full quantification, and clean treatment of platinum group metals in spent catalysts.

At the same time, because there are many types of spent catalysts, and the surface area carbon, poisoning and oxidation degree of active components of different spent catalysts are very different, and the content of silicon and aluminum components in the matrix is ​​different. Feasible recovery methods may not be able to meet the requirements for another type of spent catalyst resource recovery, especially with the continuous development of automobile exhaust catalysts, cordierite-type waste automobile exhaust three-way catalysts with high silicon and high aluminum content have gradually become the current waste The most common types of automotive exhaust catalysts

But so far, there is still a lack of key technologies for efficient cleaning and recycling of such platinum-group metal-containing spent catalysts.

On the other hand, my country's current recycling and processing enterprises of invalid platinum group catalysts are small and scattered, numerous and chaotic, fighting independently, and have not formed a coordinated and smooth material circulation chain, centralized processing of platinum group metal refining, and information supervision covering the entire recovery process Network, there is a large risk of resource dispersion and loss and environmental pollution in the process of resource recovery and treatment, and there is a big gap with the current advanced mode and level of centralized recovery and treatment in the world (for example, the European Union has established a full-process supervision of automobile exhaust gas platinum group catalysts Network, all platinum group metals recycling and refining has been concentrated in one enterprise, the Umicore precious metal refinery (Umicore) located in Hoboken (Hoboken), southwest of Antwerp, Belgium, which not only greatly improves the platinum group metals output, which saves production costs, and also reduces pollution, realizes the centralized and effective recycling of platinum group metals in waste automobile exhaust catalysts, and ensures that the entire recycling process is more environmentally friendly and efficient

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