04343706 is referenced by 46 patents and cites 11 patents.

Heavy Metals contained in industrial waste streams are removed therefrom by flocculation using a source of ferric ions and an alkaline material at a basic pH. Both the flocculated heavy metals and the coagulant chemicals are recovered by acidifying the floc to a pH of between 3.2 and 3.7. This liberates the heavy metals back into solution but does not destroy the floc particles. After separation and removal of the concentrated heavy metal solution, the floc is further acidified to completely dissolve it. This dissolved ferric ion containing solution may then be reused to treat succeeding portions of heavy metal containing waste streams. The concentrated heavy metals solution may also be recycled or the metals contained therein recovered for reuse or disposed of in an acceptable manner.

Title
Method of removing heavy metals from industrial waste streams
Application Number
6/174987
Publication Number
4343706
Application Date
August 4, 1980
Publication Date
August 10, 1982
Inventor
Praveen Anand
West Lafayette
IN, US
James E Etzel
West Lafayette
IN, US
Agent
Biebel French & Nauman
Assignee
Purdue Research Foundation
IN, US
IPC
C02F 1/52
View Original Source