Patent ID: 7060245

Claim:
A process for the continuous refining of litharge having a starting content of metallic lead of about 1 to about 30% by weight to litharge having a residual reduced content of metallic lead of less than about 10% by weight in a reaction section of a loopreactor, comprising steps of: introducing a first fluid stream, the first fluid stream comprising a solid feedstock material and a first gaseous fluid, into said reaction section of said loopreactor via an inlet section, wherein said solid feedstock material comprises lead oxide and metallic lead, introducing a second fluid stream comprising said first gaseous fluid into said reaction section via a by-pass section, said by-pass section being located in the reaction section of said loopreactor downstream to said inlet section, mixing said first fluid stream with said second fluid stream in said reaction section by propelling the first fluid stream and second fluid stream to form a resultant, still-reacting mixture in a direction which is essentially tangential to the initial direction of said first fluid stream, thereby reacting at least a portion of the solid feedstock material with said first gaseous fluid, passing said resultant, still-reacting mixture through a curved path in said reaction section, the curved path being defined by a tractrix antifriction curvature through a classification section which is defined partially by a continuation of said tractrix curvature, said resultant, still-reacting mixture being divided into heavier particles containing a partially reduced, higher content of non-reacted metallic lead and lighter particles containing a partially reduced lower content of non-reacted metallic lead with said classification section, adjusting the number of reaction cycles by adjusting the particle velocity, reaction time and reaction temperature within said reaction section to provide the desired reduced residual content of metallic lead of said lead oxide when passing an outlet section, separating said lighter particles from the classification section via said outlet section by introducing a second gaseous fluid via an injection section into said reaction section at a location downstream to said outlet section to reaccelerate the particle velocity and to interfere with said first fluid stream, said resultant still-reacting mixture and said second fluid stream.