Abstract: 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 r
Type:
Grant
Filed:
November 27, 2008
Date of Patent:
April 2, 2013
Assignee:
Engitec Technologies S.p.A.
Inventors:
Massimo Maccagni, Silvano Cossali, Carmelita Roncaldier, Carlo Olper, Luigi Olper, Alessandro Olper
Abstract: A method for selective dissolution of tin and/or lead- or tin-containing alloys from printed circuit boards is provided comprising contacting a printed circuit board with a solution comprising Ti(IV) and an acid which forms stable and soluble salt of Ti(III), Ti(IV), Sn(II) and Pb(II), under conditions to effect dissolution of substantially all of the Sn and/or Pb- or Sn-containing alloy therefrom, as Sn(II) and/or Pb(II) and recovering from the solution by electrolytic reduction substantially all of the Sn(II) and/or PB(II) species as Sn and/or Pb. After the electrolytic reduction step, the oxidant metal species is regenerated by oxidation and recycled to the first stage of the process.
Type:
Grant
Filed:
October 10, 2001
Date of Patent:
November 4, 2003
Assignee:
Alpha Fry Limited
Inventors:
Robert William Gibson, Paul David Goodman, Lyn Holt, Ian McCrady Dalrymple, Derek John Fray
Abstract: A microfluidic device having a coating on a surface which surface properties can be altered by applying an external stimulus. Such a surface change may be used to guide or direct fluid on these surfaces, thus controlling flow in the microfluidic system.
Abstract: An electrowinning process for lead incorporating a variety of alkanesulfonic acid-based electrolytes in the absence of a redox couple, is disclosed; an inert anode and a lead accepting cathode are utilized.
Abstract: A process for the direct recovery of metallic lead from battery paste in an electrolysis unit is disclosed. The electrolysis unit consists of an anode compartment and a cathode compartment separated by an ion selective membrane. The cathode consists of a high surface area electrically conductive substrate. Solid particles of battery paste are introduced into the cathode compartment which contains a liquid electrolyte and a complexing agent. Metallic lead is electrochemically deposited on the cathode, and sulfuric acid is produced in the anode compartment.
Type:
Grant
Filed:
July 5, 1995
Date of Patent:
May 7, 1996
Assignee:
H. J. Enthoven Limited
Inventors:
Johannus B. J. Spijkerman, Rudolf J. M. Groenen