Metals Technology Development Company LLC

Engitec Technologies S.p.a.

Ecochem Aktiengesellschaft

Engitec S.p.a.

Engitec S.r.l.

Massimo Giuseppe Maccagni

Marco Olper

Silvano Cossali

William Leonard Lane

Timothy Roy Hymer

David Michael Olkkonen

Jonathan Hylkjier Nielsen

Bruce David Chamberlain

Edoardo Guerrini

Karl Friedrich Schneider

Jonathan Hylkjier Nielson

The present invention concerns a process for the recovery of lead from a lead pastel electrolytically, where the pastel contains lead sulfate. The process provides for the leaching of the non-desulfurised pastel and the subsequent removal of the sulfates by precipitation; the leachate containing the lead ions is then subjected to electrolysis for the recovery of metal lead. The present invention further relates to a process for the recovery of lead accumulator components, wherein the lead contained in the pastel of the accumulators is recovered according to the aforesaid process.

Process for recovering lead from a lead pastel and use thereof in a process for recovering lead-acid accumulator components

A process for recovering non-ferrous metals from a solid matrix may include: (a) leaching the solid matrix with an aqueous-based solution containing chloride ions, ammonium ions, and Cuions, having a pH of 6.5-8.5, in a presence of oxygen, at a temperature of 100&#xb0; C.-160&#xb0; C. and a pressure of 150 kPa-800 kPa, so as to obtain an extraction solution comprising leached metals and solid leaching residue; (b) separating the solid leaching residue from the extraction solution; and/or (c) subjecting the extraction solution to at least one cementation so as to recover the leached metals in elemental state. The pH may be greater than or equal to 6.5 and less than or equal to 8.5. Temperature may be greater than or equal to 100&#xb0; C. and less than or equal to 160&#xb0; C. Pressure may be greater than or equal to 150 kPa and less than or equal to 800 kPa.

Processes for recovering non-ferrous metals from solid matrices

A process for recovering non-ferrous metals from a solid matrix may include: leaching the solid matrix with an aqueous-based solution, in a presence of oxygen, to obtain an extraction solution including leached metals and solid leaching residue; separating the solid leaching residue from the extraction solution; and subjecting the extraction solution to at least one cementation to recover the leached metals in elemental state. The leaching solution may include chloride ions. The leaching solution may further include ammonium ions. A pH of the leaching solution may be greater than or equal to 6.5 and less than or equal to 8.5. A leaching temperature may be greater than or equal to 100&#xb0; C. and less than or equal to 160&#xb0; C. A leaching pressure may be greater than or equal to 150 kPa and less than or equal to 800 kPa.

A method of recovering metal values from metal-bearing materials such as slags and drosses includes the steps of pulverizing the material to particles less than about 100 &#x3bc;m; leaching the pulverized material with a solution of ammonium chloride, sodium chloride, and potassium chloride; sequentially recovering at least two metals from the leachate by the addition of zinc using a sequential cementation process; and recovering zinc from the solution by electrowinning.

System and method for the recovery of metal values from slags, drosses, and other metal-bearing materials

A system for recovering lead from lead-bearing materials by circulating an aqueous solution of ferric fluoroborate in fluoroboric acid through a leaching vessel to leach lead from the lead-bearing material and an electrolytic cell for recovering the lead includes a cooler for cooling at least a portion of the circulating solution sufficiently to precipitate alkali salts and alkali-earth salts, and a filter for removing the precipitated salts from the solution. A process for recovering lead from lead-bearing materials by leaching the lead from the lead-bearing material with a solution of ferric fluoroborate in fluoroboric acid and recovering the lead from the solution includes cooling at least a portion of the circulating solution sufficiently to precipitate alkali salts and alkali-earth salts, and filtering the salts from the solution.

Process for the recovery of lead from lead-bearing materials

The present invention relates to an electrolytic process for producing metallic lead starting from desulfurized lead pastel comprising the following operative phases: a) leaching the desulfurized pastel by putting it in contact with a solution comprising ammonium chloride, with the formation of a leach liquor and evolution of gaseous CO2; b) separating a first solid residue and a first clarified leach liquor from the leach liquor coming from phase a); c) leaching the solid residue separated in phase b) by putting it in contact with a solution comprising ammonium chloride and hydrogen peroxide; d) separating a second solid residue and a second clarified leach liquor from the leach liquor coming from phase c); e) joining the first clarified leach liquor coming from phase b) with the second clarified leach liquor coming from phase d) and forming a single solution; f) subjecting the solution leaving phase e) to electrolysis in a flow cell, with a current density ranging from 50 to 10,000 A/m2, said electrolysis resulting in the formation of a lead sponge. The present invention also relates to the relative desulfurization process of the pastel.

Process for producing metallic lead starting from desulfurized pastel

The present invention relates to a process for the recovery of elemental sulphur from residues produced in hydrometallurgical processes based on leaching with a solution of sodium sulphide in which the sulphur contained in the residues is selectively leached as sodium polysulphide. The sulphur leaching solution is conveniently regenerated and recycled to the process.

Process for the recovery of elemental sulphur from residues produced in hydrometallurgical processes

The present invention relates to a desulfurization process of pastel and grids of lead accumulators comprising a carbonation in two steps, a granulometric separation between the two steps followed by specific desulfurization of the large part, a desodification obtaining the conversion of the PbSOcontained in the pastel into PbCOwhich can be easily converted into metallic Pb in an oven by the addition of coal. The system used for the desodification of the large part of the pastel can also be used for the desulfurization of the fine part of the grids.

Desulfurization process of pastel and grids of lead accumulators

A process is disclosed for treating lead paste from exhausted batteries. Calcium sulfite and calcium thiosulfite are formed by the reaction:

Process for regenerating sodium sulphide from the sodium sulphate which

A wet process of regenerative type for removing SO.sub.2 contained in combustion gases in which SO.sub.2 is caused to be absorbed by a diluted aqueous solution of BaS, with a mixed precipitate of elemental S, BaSO.sub.3 and BaSO.sub.4 being formed by the consequent reactions. Sulfur is extracted from the precipitate--recovered by filtration--by using a solution of (NH.sub.4).sub.2 S; the resulting polysulfide is distilled, with pure elemental S and the solution of (NH.sub.4).sub.2 S to be recycled, being obtained. The residual mixture of BaSO.sub.3 and BaSO.sub.4 remaining after sulfur extraction is reduced with coal in a high temperature furnace, in order to obtain BaS to be recycled, as an aqueous solution, to the SO.sub.2 absorption step.

Growing community of inventors

Sesto San Giovanni, Italy

Massimo Giuseppe Maccagni