Method for preparing high-purity lead compound through wet recovery and impurity removal of waste lead plaster

Abstract

The invention discloses a method for preparing a high-purity lead compound through wet recovery and impurity removal of waste lead plaster. The method comprises the following steps that 1, strong basecontaining Na and K elements is used as a basic desulfurizer for carrying out normal-temperature desulfuration on waste lead paster, the obtained desulfurated lead paster reacts with an acid leachingagent mixed with a hydrogen peroxide reducing agent, after reaction is finished, a lead salt solution is obtained by adjusting the pH value and carrying out filtration according to the variety of theacid leaching agent, or the lead salt solution is obtained through direct filtration; 2, the lead salt solution is subjected to liquid phase reaction conversion to prepare a solid phase lead compound, and lead oxide and other products can also be produced through follow-up roasting. By means of the whole process technological set of wet recovery and parameter conditions adopted by key technologysteps are improved and optimized, the high-purity lead compound (and high-purity lead oxide) can be prepared from waste lead paster through an acid leaching wet recovery method, and the problems thattwo impurity elements Ba and Fe are high in content and not likely to be removed are solved.

Description

technical field [0001] The invention belongs to the field of recycling and regenerating lead of waste lead-acid storage batteries, and more specifically relates to a method for wet recovery and removal of impurities from waste lead paste and preparation of high-purity lead compounds. Background technique [0002] Lead-containing waste in waste lead-acid batteries mainly includes grids and waste lead paste. Among them, waste lead paste has complex components, including three lead-containing substances with different valence states and different types of metal impurities, which is the most difficult part to clean and treat efficiently. It contains a large amount of lead sulfate, because the melting point is above 1000 °C, the current pyro-smelting process not only consumes a lot of energy, but also produces a large amount of SO 2 and lead-containing smoke pollution. [0003] In order to solve the problem of pyrothermal high-temperature smelting recovery process, some scholar...

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Problems solved by technology

[0009] For the above defects or improvement needs of the prior art, the object of the present invention is to provide a method for wet recovery of waste lead plaster to remove impurities and prepare high-purity lead compounds, wherein the overall flow process of wet recovery is set, and The parameters and conditions (including pH requirements, specific types and proportions of reagents) used in key process steps (such as desulfurization steps, leaching steps, etc.) are improved and optimized, and waste lead paste is used as raw material for recovery and preparation by acid immersion wet method. Obtain high-purity lead compounds (and high-purity lead oxides, high-purity lead oxides can be obtained through subsequent roasting processes), especially for the high impurity content that is generally present in the current acid soaking wet process for recycling waste lead paste, especially The more harmful Ba elements and Fe elements are high in content and difficult to remove, which can effectively solve the problem that the impurity content of the recycled lead products exceeds the standard, and avoid the adverse effects of impurities on the subsequent utilization of the recycled lead products (for example, affecting the newly produced lead storage battery. capacity and lifetime, etc.); and, by utilizing optimal parameter conditions (such as pH value requirements, specific types and proportions of reagents used, etc.) in each step, the recovery rate of lead can be further ensured

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