Catherine A Simmons

US Patent:

43338470, Jun 8, 1982

Filed:

Aug 10, 1979

Appl. No.:

6/065752

Inventors:

Danh C. Tran - Rockville MD
Pedro B. Macedo - Bethesda MD
Joseph H. Simmons - Bethesda MD
Catherine J. Simmons - Bethesda MD
Nicholas Lagakos - Silver Spring MD

International Classification:

G21F 916

US Classification:

252629

Abstract:

This invention relates to the immobilization of toxic, e. g. , radioactive materials, internally in a silicate glass or silica gel matrix for extremely long periods of time. Toxic materials, such as radioactive wastes containing radioactive anions, and in some cases cations, which may be in the form of liquids, or solids dissolved or dispersed in liquids or gases, are internally incorporated into a glass matrix, having hydrous organofunctionalsiloxy groups, e. g. , hydrous aminoalkylsiloxy or carboxyorganosiloxy, bonded to silicon atoms of said glass and/or hydrous polyvalent metals bonded to silicon atoms of said glass through divalent oxygen linkages or otherwise immobilized therein, by a process which involves the ion exchange of said toxic, radioactive anions with hydroxyl groups attached to said organofunctionalsiloxy groups or with hydroxyl groups attached to the hydrous polyvalent metal. Thereafter, the resulting glass now characterized by a distribution of internally bonded or immobilized, toxic, radioactive anions can be packaged in suitable containers, and disposed of as by burial, and/or they can be sintered to collapse the pores thereof prior to disposal or for producing useful radiation sources. The porous glass or a porous silica gel having said silicon-bonded organofunctionalsiloxy groups and/or said hydrous polyvalent metal oxy groups, the pores of said glass or silica gel remaining open and uncollapsed, can be used advantageously as a backfill for an underground radioactive waste burial site and as overpack in the waste disposal container.

US Patent:

43127746, Jan 26, 1982

Filed:

Apr 30, 1979

Appl. No.:

6/034567

Inventors:

Pedro B. Macedo - Bethesda MD
Catherine J. Simmons - Bethesda MD
Danh C. Tran - Rockville MD
Nicholas Lagakos - Silver Spring MD
Joseph Simmons - Bethesda MD

International Classification:

G21F 916

US Classification:

252629

Abstract:

This invention relates to the immobilization of toxic materials, e. g. , radioactive materials, in glass for extremely long periods of time. Toxic materials, such as radioactive wastes, which may be in the form of liquids, or solids dissolved or dispersed in liquids or gases, are deposited in a glass container which is heated to evaporate off non-radioactive volatile materials, if present; to decompose salts, such as nitrates, if any, and to drive off volatile non-radioactive decomposition products, and then to collapse the walls of said container on said radwaste and seal the container and immobilize the contained radwaste, and then burying the resulting product underground or at sea. In another embodiment, the glass container also contains glass particles, e. g. , spheres or granules, on which the radwaste solids are deposited.

US Patent:

47373164, Apr 12, 1988

Filed:

May 20, 1986

Appl. No.:

6/865017

Inventors:

Pedro B. Macedo - Bethesda MD
Herbert G. Sutter - Gaithersburg MD
Robert K. Mohr - Washington DC
Catherine J. Simmons - Bethesda MD

International Classification:

G21F 916
G21F 936

US Classification:

252633

Abstract:

A liquid containing radioactive ions is purified (decontaminated) by contacting the same with an inorganic ion exchange composition having ion exchange sites which can be occupied by the radioactive ions from the liquid. The ion exchange composition is a mixture of an ion exchange medium and an additive which is relatively inert to the ion exchange process and which is a sintering aid for the ion exchange medium designed to lower the sintering temperature of the ion exchange composition. The ion exchange composition may be disposed within a suitable container (e. g. , cannister), e. g. , made of 304L stainless steel or Inconel 601 and the ion exchange process may be carried out in such container. Alternatively, the ion exchange medium can be employed without being previously admixed with the additive. The additive, if desired, can be admixed at a later stage with the contaminated medium.

US Patent:

45444994, Oct 1, 1985

Filed:

Jun 7, 1982

Appl. No.:

6/386215

Inventors:

Danh C. Tran - Rockville MD
Pedro B. Macedo - Bethesda MD
Joseph H. Simmons - Bethesda MD
Catherine J. Simmons - Bethesda MD
Nicholas Lagakos - Silver Spring MD

International Classification:

G21F 916

US Classification:

252629

Abstract:

This invention relates to the immobilization of toxic, e. g. , radioactive materials, internally in a silicate glass or silica gel matrix for extremely long periods of time. Toxic materials, such as radioactive wastes containing radioactive anions, and in some cases cations, which may be in the form of liquids, or solids dissolved or dispersed in liquids or gases, are internally incorporated into a glass matrix, having hydrous organofunctionalsiloxy groups, e. g. , hydrous aminoalkylsiloxy or carboxyorganosiloxy, bonded to silicon atoms of said glass and/or hydrous polyvalent metals bonded to silicon atoms of said glass through divalent oxygen linkages or otherwise immobilized therein, by a process which involves the ion exchange of said toxic, radioactive anions with hydroxyl groups attached to said organofunctionalsiloxy groups or with hydroxyl groups attached to the hydrous polyvalent metal. Thereafter, the resulting glass now characterized by a distribution of internally bonded or immobilized, toxic, radioactive anions can be packaged in suitable containers, and disposed of as by burial, and/or they can be sintered to collapse the pores thereof to disposal or for producing useful radiation sources. The porous glass or a porous silica gel having said silicon-bonded organofunctionalsiloxy groups and/or said hydrous polyvalent metal oxy groups, the pores of said glass or silica gel remaining open and uncollapsed, can be used advantageously as a backfill for an underground radioactive waste burial site and as overpack in the waste disposal container.

US Patent:

44696280, Sep 4, 1984

Filed:

Apr 21, 1982

Appl. No.:

6/370437

Inventors:

Catherine J. Simmons - Bethesda MD
Joseph H. Simmons - Bethesda MD
Pedro B. Macedo - Bethesda MD
Theodore A. Litovitz - Annapolis MD

International Classification:

C09K 300
C09K 1104

US Classification:

252629

Abstract:

This invention relates to the immobilization of toxic, e. g. , radioactive, materials in a silicate glass or silica gel matrix for extremely long periods of time. Toxic materials, such as radioactive wastes containing radioactive cations, which may be in the form of liquids, or solids dissolved or dispersed in liquids or gases, are incorporated into a glass or silica gel matrix, having alkali metal, Group Ib metal and/or ammonium cations bonded to silicon atoms of said glass or silica gel through divalent oxygen linkages, by a process which involves the ion exchange of said toxic or radioactive cations with said alkali metal, Group Ib metal and/or ammonium cations to bind said toxic or radioactive cations to silicon atoms of said glass or silica gel through said silicon-bonded divalent oxygen linkages. Thereafter, the resulting glass or silica gel now characterized by toxic or radioactive cations bonded to silicon atoms through divalent oxygen linkages can be stored, or packaged in suitable containers, or disposed of as by burial, and/or sintered to collapse the pores thereof.

US Patent:

45914559, May 27, 1986

Filed:

Nov 24, 1982

Appl. No.:

6/444176

Inventors:

Pedro B. Macedo - Bethesda MD
Herbert G. Sutter - Gaithersburg MD
Robert K. Mohr - Washington DC
Catherine J. Simmons - Bethesda MD

International Classification:

G21F 916

US Classification:

252629

Abstract:

A liquid containing radioactive ions is purified (decontaminated) by contacting the same with an inorganic ion exchange composition having ion exchange sites which can be occupied by the radioactive ions from the liquid. The ion exchange composition is a mixture of an ion exchange medium and an additive which is relatively inert to the ion exchange process and which is a sintering aid for the ion exchange medium designed to lower the sintering temperature of the ion exchange composition. The ion exchange composition may be disposed within a suitable container (e. g. , cannister), e. g. , made of 304L stainless steel or Inconel 601 and the ion exchange process may be carried out in such container. Alternatively, the ion exchange medium can be employed without being previously admixed with the additive. The additive, if desired, can be admixed at a later stage with the contaminated medium.

US Patent:

45280118, Jul 9, 1985

Filed:

Dec 14, 1981

Appl. No.:

6/330336

Inventors:

Pedro B. Macedo - Bethesda MD
Catherine J. Simmons - Bethesda MD
Danh C. Tran - Rockville MD
Nicholas Lagakos - Silver Spring MD
Joseph Simmons - Bethesda MD

International Classification:

C01C 2100

US Classification:

65 3013

Abstract:

This invention relates to the immobilization of toxic materials, e. g. , radioactive materials, in glass for extremely long periods of time. Toxic materials, such as radioactive wastes, which may be in the form of liquids, or solids dissolved or dispersed in liquids or gases, are deposited in a glass container which is heated to evaporate off non-radioactive volatile materials, if present; to decompose salts, such as nitrates, if any, and to drive off volatile non-radioactive decomposition products, and then to collapse the walls of said container on said radwaste and seal the container and immobilize the contained radwaste, and then burying the resulting product underground or at sea. In another embodiment, the glass container also contains glass particles, e. g. , spheres or granules, on which the radwaste solids are deposited.