Chemistry: electrical and wave energy – Processes and products – Electrostatic field or electrical discharge
Patent
1998-06-19
2000-04-18
Gorgos, Kathryn
Chemistry: electrical and wave energy
Processes and products
Electrostatic field or electrical discharge
H05F 0300
Patent
active
060511125
DESCRIPTION:
BRIEF SUMMARY
The present invention relates to improvements to the so-called "electrostatic pseudo liquid membrane" (ESPLIM) method of separation of metal ions from aqueous solutions.
Chinese patent application number CN 86101730A describes a separation technique which enables the purification of aqueous solutions and concentration of solutes in aqueous solutions.
The technique includes the steps of passing droplets of an aqueous feed solution which it is desired to purify and/or from which it is desired to extract metal ions for example, under the influence of gravity, through a first region of a non-polar carrier liquid in which is dissolved a chemical having high affinity for the metal ion or ions to be removed whilst simultaneously subjecting the droplets to a high voltage electrostatic field so as to break up the droplets into a multiplicity of much smaller droplets in order to increase their surface area to volume ratio. The metal ions are complexed by the dissolved chemical into the carrier liquid and are driven, principally by the concentration gradient so formed, to a second region in the non-polar carrier liquid through which is passing under the influence of gravity a stream of droplets of an aqueous "stripping" solution which has a chemically higher affinity for the metal ion than the complexing chemical in the carrier liquid. The stripping solution droplets are also simultaneously subjected to a high voltage electrostatic field so as to break them up into a multiplicity of much smaller droplets and thus to increase their surface area to volume ratio. The metal ions are thus concentrated into the stripping solution and the aqueous feed solution is largely purified of the metal ions. As the very small droplets of the purified feed solution and the stripping solution, the former now having a lower concentration of the metal ions and the latter now having a high concentration of the required metal ions, pass out of the high voltage electrostatic field, they coalesce and fall under gravity into mutually separated first and second collecting vessels, respectively, and from which they can be removed.
The first and second regions of the carrier liquid are separated by a barrier or baffle which is intended to allow substantially uninterrupted flow and passage of the carrier liquid to and from the first and second regions but, is also intended to impede or prevent the passage of the aqueous feed solution from the first region into the second region and, the passage of the stripping solution from the second region to the first region.
According to a first aspect of the present invention, there is provided a method for the extraction of a solute from an aqueous feed solution into an aqueous stripping solution, the method comprising the steps of providing at least one stream of each of said feed solution and said stripping solution passing through a continuous phase of a non-polar carrier liquid; said carrier liquid having therein a chemical having an affinity for ions of at least one species in said solute in said feed solution; each of said at least one streams of feed and stripping solutions being under the influence of a first and a second high voltage electrostatic field, respectively, for at least a part of their passage time through said carrier liquid so as to break up said streams into a multiplicity of droplets of each of said solutions; providing baffle means between said at least one streams of each of the feed and stripping solutions, the baffle means being to minimise transfer of feed solution towards said stripping solution stream and transfer of said stripping solution towards said feed solution stream; said baffle means also being positioned between the separate high voltage electrostatic fields to which the feed and stripping solution streams are subjected; and, providing mutually separated receiving means to collect the streams of said feed and said stripping solutions after they pass out of said high voltage electrostatic field; said method being characterised in that said high voltage electrostatic
REFERENCES:
patent: 4033851 (1977-07-01), Oros
patent: 4161439 (1979-07-01), Warren et al.
patent: 4200516 (1980-04-01), Pope
patent: 4224124 (1980-09-01), Pope
patent: 4606801 (1986-08-01), Prestridge et al.
patent: 4634510 (1987-01-01), Mintz et al.
patent: 5385658 (1995-01-01), Scott
patent: 5411651 (1995-05-01), Yamaguchi et al.
Zhong-Mao Gu, A new Liquid Membrane Technology-Electrostatic Pseudo Liquid Membrane, J. of Membrane Science Abstract XP 000172713, 52(1):77-88 Aug. 15, 1990.
Bailey Adrian George
Broan Christopher John
Williams Trevor James
British Nuclear Fuels PLC
Brown Jonathan
Gorgos Kathryn
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