1
Dhiraj Pal, Karl Yost: Fixation and stabilization of lead in contaminated soil and solid waste. MAECORP Incorporated, Andrew B Katz, Leonard D Bowersox, March 16, 1993: US05193936 (49 worldwide citation)

A two-step treatment process is disclosed for application of lead-toxic wastes to fixate and stabilize leachable lead contained therein. The process employs the use of a sulfate compound, such as gypsum, in a first step; and a phosphate reagent, such as phosphoric acid, in a second step. After thoro ...


2
Dhiraj Pal, Karl W Yost: Fixation and stabilization of chromium in contaminated materials. Sevenson Environmental Services, Kevin E McDermott, March 14, 1995: US05397478 (28 worldwide citation)

A highly flexible multi-step treatment technology for chemical fixation and stabilization of leachable chromium, particularly hexavalent chrome, in contaminated soils, solid wastes, concrete, sludge, sand and gravel and waste waters is disclosed. The process comprises reducing hexavalent chromium to ...


3
Dhiraj Pal, Karl W Yost: Fixation and stabilization of metals in contaminated materials. Sevenson Environmental Services, Kevin E McDermott, June 18, 1996: US05527982 (23 worldwide citation)

The present invention discloses a method of treating lead bearing process materials and lead toxic hazardous wastes. The invention relates to treatment methods employed to chemically convert leachable lead in lead bearing solid and liquid waste materials to a non-leachable form by mixing the materia ...


4
Dhiraj Pal, Karl W Yost: Fixation and stabilization of metals in contaminated materials. Sevenson Environmental Services, Kevin E McDermott, October 29, 1996: US05569155 (16 worldwide citation)

The present invention discloses a method of treating lead bearing process materials and lead toxic hazardous wastes. The invention relates to treatment methods employed to chemically convert leachable lead in lead bearing solid and liquid waste materials to a non-leachable form by mixing the materia ...


5
Dhiraj Pal, Karl W Yost: Fixation and stabilization of metals in contaminated soils and materials. Sevenson Environmental Services, Kevin E McDermott, October 31, 2000: US06139485 (6 worldwide citation)

The present invention discloses a method of treating lead-bearing soils, waste materials and waste material matrixes. The invention relates to treatment methods employed to chemically convert leachable lead in lead-bearing solid and/or liquid waste materials to a non-leachable form by contacting or ...


6
Dhiraj Pal, Karl W Yost: Fixation and stabilization of metals in contaminated soils and materials. Sevenson Environmental Services, Kevin E McDermott, June 29, 1999: US05916123 (6 worldwide citation)

The present invention discloses a method of treating lead bearing process materials and lead toxic hazardous wastes. The invention relates to treatment methods employed to chemically convert leachable lead in lead bearing solid and liquid waste materials to a non-leachable form by mixing the materia ...


7
Dhiraj Pal, Karl W Yost, Steven A Chisick: Fixation and stabilization of metals in contaminated soils and materials. Sevenson Environmental Services, Kevin E McDermott, July 10, 2001: US06258018 (4 worldwide citation)

The present invention discloses a method of treating heavy metal bearing process materials and heavy metal toxic hazardous wastes. The invention relates to treatment methods employed to chemically convert leachable heavy metals in heavy metal bearing solid and/or liquid waste materials to a non-leac ...


8
Dhiraj Pal, Karl W Yost, Steven A Chisick: Reduction of leachability and solubility of radionuclides and radioactive substances in contaminated soils and materials. Sevenson Environmental Services, October 21, 2003: US06635796 (2 worldwide citation)

A process for chemical fixation of radionuclides and radioactive compounds present in soils, solid materials, sludges and liquids. Radionuclides and other radioactive compounds are converted to low-temperature Apatite-Group structural isomorphs (general composition: (AB)


9
Dhiraj Pal, Karl W Yost, Steven A Chisick: Reduction of leachability and solubility of radionuclides and radioactive substances in contaminated soils and materials. Sevenson Environmental Services, Kevin E McDermott, September 18, 2001: US06291736 (1 worldwide citation)

A process for chemical fixation of radionuclides and radioactive compounds present in soils, solid materials, sludges and liquids. Radionuclides and other radioactive compounds are converted to low-temperature Apatite-Group structural isomorphs (general composition: (AB)


10
Dhiraj Pal, Karl W Yost: Method of forming an insoluble phosphate mineral species. Sevenson Environmental Services, October 30, 2001: US06309337 (1 worldwide citation)

The present invention discloses a method of forming phosphate mineral species of the apatite family, and the mineral species thus formed, by contacting soil or solid waste material containing leachable lead with a combination of a sulfate reagent that includes one or more reactive sulfate ions and a ...