Method of recovering noble metal from spent catalyst containing noble metal

Abstract

The method of recovering noble metal from waste catalyst containing noble metal includes the first pre-treatment of waste catalyst containing noble metal to make noble metal exist in reductive state favorable to further treatment; the subsequent leaching of the waste catalyst with mixed solution containing hydrogen dioxide solution, hydrogen ion and chlorine ion to make the noble metal component exist in ion state in the mixed solution; and the final treatment of the mixed solution containing noble metal ion to recover noble metal component. Compared with available technology, the present invention has less investment, simple technological process, less pollution, short time consumption, high recovering rate and being easy use in industrial production.

Description

1. Technical field [0001] The invention belongs to a method for recovering metal components from spent catalysts, more specifically, relates to a method for recovering precious metals from spent catalysts containing precious metals. 2. Background technology [0002] With the advancement of science and technology and the improvement of environmental regulations, precious metals are not limited to making decorations and playing a role in economics and finance, but also have been used in industrial production processes, especially in the catalysts used in petrochemical processes. application. [0003] Precious metals such as palladium and platinum play an important and irreplaceable role in various fields due to their unique physical and chemical properties. However, my country's palladium and platinum resources are very scarce, and the price is very expensive, while the domestic demand is increasing year by year, and more than 90w% of the domestic demand needs to be imported....

AI Technical Summary

Problems solved by technology

For example: U.S. Patent US5102632 proposes to recover precious metals from waste materials containing precious metals by using a two-stage method. First, high-temperature treatment, chlorination, and then leaching with aqua regia, the operation is cumbersome, expensive, dangerous, and serious environmental pollution; In US4331634, 4578250, 5045290, 5324851, 5302183, 5654458, 5503812 and EP0538168, 0585489, each proposes a method for recovering precious metals from different raw materials. The process is to first carry out high-temperature treatment of waste materials, and carry out conventional dissolution of pretreated samples , and then use different organic solvents to extract and recover precious metals. These methods also have the disadvantages of time-consuming, complicated process, high investment and operating costs, and easy to cause serious environmental pollution; The recovery method is to firstly carry out high-temperature treatment on the waste containing precious metals, and at the same time remove impurities, make the precious metals exist in the form of oxides, but because the oxides of these precious metals are relatively stable, it is necessary to use aqua regia to immerse them under harsh conditions. This will inevitably cause serious waste of resources and environmental pollution, and the recovery rate of precious metals is low

[0005] For example, Chinese patents ZL95104435.4 and 91104385.3 provide a method for recovering palladium from spent palladium / carbon catalysts. First, the raw materials are subjected to high-temperature roasting pretreatment to remove impurities while making the palladium on the catalyst exist in the form of oxides. The waste material of treatment carries out reduction treatment again, and used reductant is formaldehyde or formic acid, and then leaching with aqua regia, finally recover metal palladium through reduction, purification etc. Disadvantages such as low recovery rate