A reducing ion-exchange membrane for treating sewage containing precious metals and recovering high-purity precious metals, and its preparation and application

Abstract

The invention belongs to the field of precious metal sewage recovery and treatment, and relates to a reducing ion exchange membrane for treating precious metal sewage and recovering high-purity precious metal elemental substance and its preparation and application. 3 The membrane prepared from the powder is used as a reducing ion exchange membrane material. First, it is filled with hydrogen ions in an acidic solution to make it into a reduced state, and then it is placed in sewage containing noble metal ions so that the noble metal ions are reduced on the surface of the reducing ion exchange membrane. It is a simple substance, and the restored precious metal simple substance can be easily recovered. The device used in the method is simple and does not need to consume a large amount of chemical reagents. Using hydrogen ions as exchange ions can avoid secondary pollution. The membrane has a high degree of stability in acidic environments and can be directly applied in acidic precious metal sewage. WO 3 It has a suitable oxidation-reduction potential, is highly selective to noble metal ions, can easily and quickly recover noble metals in a single substance state, and has excellent recycling performance.

Description

technical field [0001] The invention relates to a reductive ion exchange technology based on tungsten trioxide that is used for precious metal sewage treatment and effectively recovers high-purity precious metal simple substances, and belongs to the field of precious metal sewage recovery and treatment. Background technique [0002] The information disclosed in this background section is only intended to increase the understanding of the general background of the present invention, and is not necessarily taken as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to those skilled in the art. [0003] Precious metals mainly include 8 kinds of metal elements, such as gold, silver, palladium and platinum, etc. Due to their unique physical and chemical properties, such as excellent catalytic activity, good electrical conductivity and corrosion resistance, they are widely used in jewelry, electronic equipment, catalysts, etc. ...

AI Technical Summary

Problems solved by technology

Among them, chemical sedimentation, flocculation and coagulation methods need to add a large amount of chemical reagents such as settling agent, flocculant and coagulant, which increases the operating cost and has low removal efficiency. The product is usually sludge containing precious metal ions, which requires secondary treatment Recovery; ion exchange method requires pretreatment of ion exchange materials, high operating costs, and the treatment effect is highly dependent on the type of target metal element, which is not suitable for simultaneous removal of multiple precious metals; membrane filtration method is limited by membrane fouling and poor cycle stability; adsorption Due to the limited capacity, the amount of precious metal sewage that can be effectively treated is low; the electrochemical method is not suitable for the recovery of low-concentration precious metal ion sewage due to the low diffusion current density, and the removal efficiency of this method is relatively low

Some researchers use self-made coal-based materials as working electrodes, apply a certain voltage, and recover precious metal elements in low-concentration precious metal wastewater, but this process requires a large amount of electric energy input, and the system needs to be heated during the recovery process. Precious metals can be effectively recovered at a suitable temperature. This electrochemical reaction process is costly and consumes a lot. It can only enrich precious metal ions and cannot directly recover precious metals.

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