Method for recovering lead oxide from waste lead paste

Patent metadata

Field	Value
Publication number	US-10135100-B2
Application number	US-201515505608-A
Country	US
Kind code	B2
Filing date	Jun 10, 2015
Priority date	Aug 20, 2014
Publication date	Nov 20, 2018
Grant date	Nov 20, 2018

Abstract

A method for recovering lead oxide from a pre-desalted lead paste, comprising the following steps: a. dissolving the pre-desalted lead plaster by using a complexing agent solution, and making all of PbO therein react with the complexing agent to generate lead complexing ions, obtaining a lead-containing solution and a filter residue; b. adding a precipitant to the lead-containing solution, and then the precipitant reacting with the lead complexing ions to generate a lead salt precipitate and the regenerated complexing agent; c. calcining the lead salt precipitate to obtain lead oxide and regenerate the precipitant. The final recovery rate of lead oxide of the method can reach 99% or more.

First claim

The invention claimed is:

1. A method for recovering lead oxide from pre-desalted lead paste, comprising the following steps:
a. dissolving pre-desalted lead paste with a complexing agent solution, so that all PbO in the pre-desalted lead paste reacts with the complexing agent to generate lead complexing ions and thereby obtain a lead-containing solution and a filter residue, wherein the PbO originates from the PbO in the pre-desalted lead paste and PbO generated in a reaction between the Pb and PbO 2 from the pre-desalted lead paste in the complexing agent solution and further includes PbO obtained from oxidation of the Pb in the pre-desalted lead paste or from reduction of the PbO 2 in the pre-desalted lead paste, and wherein the complexing agent is a compound having amino and carboxyl groups, an organic amine, an alcohol amine or salts thereof;
b. adding a precipitant into the lead-containing solution, so that the precipitant reacts with the lead complexing ions to generate a lead salt precipitate and a regenerated complexing agent, wherein, the precipitant is gaseous CO 2 , SO 2 , SO 3 or a water solution thereof;
c. calcining the lead salt precipitate to obtain lead oxide and regenerate the precipitant.

2. The method according to claim 1 , wherein, the pre-desalted lead paste is a product obtained by reaction between the lead paste and an alkaline liquor in which the lead salts included in the lead paste are removed, wherein the lead salt is PbSO 4 , PbSO 3 , Pb(CH 3 COO) 2 , Pb(NO 3 ) 2 , Pb(ClO 4 ) 2 or PbCO 3 , the alkaline liquor is a water solution of NaOH, KOH, ammonia, or Ba(OH) 2 in which the concentration in weight percentage is 0.5-40%, and the desalting time is 0.5-60 min.

3. The method according to claim 1 , wherein, the compound having amino and carboxyl groups is α-amino acid, ethylene diammine diacetate, ethylenediamine tetraacetic acid, propanediamine diacetic acid, iminodiacetic acid, glucosaminic acid, or alginic acid; and wherein the organic amine is methyl amine, ethylene diamine, propylene diamine, diethylene triamine, or triethylene tetramine; and wherein the alcohol amine is ethanolamine, di-ethanolamine, or tri-ethanolamine.

4. The method according to claim 1 , wherein, in the step a, a catalyst is added into the complexing agent solution to accelerate the oxidation-reduction reaction between Pb and PbO 2 that generates PbO, wherein, the catalyst is metal powder of Cu, Co, Ni, or Ag, or chlorides, oxides or nitrates of the metal.

5. The method according to claim 1 , wherein,
additional lead is added in the step a, so as to fully reduce PbO 2 to PbO; or
oxygen is injected into the complexing agent solution in the step a, so as to fully convert Pb into PbO; or
the pre-desalted lead paste is treated with H 2 O 2 solution, so as to fully oxidize Pb to PbO, or fully reduce PbO 2 to PbO.

6. The method according to claim 1 , wherein, the regenerated complexing agent obtained in the step b is returned to the step a and reused; and/or the regenerated precipitant obtained in the step c is returned to the step b and reused; wherein, both the step a and the step b are performed within a water solution temperature range of 5-110° C.

7. The method according to claim 3 , wherein, the α-amino acid is aspartic acid, methionine, valine, lysine, isoleucine, phenylalanine, tryptophane, threonine, glycine, proline, histidine, glutamic acid, serine, arginine, sarcosine or citrulline.

Assignees

• Univ Beijing Chem Tech

Inventors

• Pan Junqing
• Bian Yaru
• Sun Yanzhi
• Niu Yinjian

Classifications

• Y02W30/84

  Recycling of batteries or fuel cells · CPC title

• H01M10/54 Primary

  Reclaiming serviceable parts of waste accumulators · CPC title

• H01M10/06

  Lead-acid accumulators (semi-lead accumulators H01M10/20) · CPC title

• C01G21/14

  Carbonates · CPC title

• H01M4/56

  of lead · CPC title