Patents by Inventor Manilal S. Dahanayake

Manilal S. Dahanayake has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20090149557
    Abstract: Demulsifiers containing an anionic surfactant selected from alkylsulfosuccinates, alkylphosphonic acids, and their salts; a nonionic surfactant selected from ethylene oxide/propylene oxide copolymers, ethoxylated fatty acids of polyethylene glycol, terpene alkoxylates, and modified alkanolamides; and solvent bases comprising blends of dibasic esters. Methods for breaking emulsions using such demulsifiers and solvent bases are also disclosed.
    Type: Application
    Filed: January 7, 2009
    Publication date: June 11, 2009
    Applicant: RHODIA INC.
    Inventors: Ruela Talingting-Pabalan, Gary Woodward, Manilal S. Dahanayake, Herve Adam
  • Publication number: 20090065204
    Abstract: There is a method for enhancing the recovery of oil from a reservoir. The method has the step of a) introducing a flooding fluid into the reservoir and b) extracting the oil through a wellbore at a location different than the point of introduction of the flooding fluid into the reservoir. The flooding fluid has water and an amount of one or more non-polymeric viscoelastic surfactants sufficient to provide an interfacial surface tension of about 1 mNm or less and a viscosity of about 10 cps or more. The one or more surfactants is selected from the group of one or more cationic surfactants, one or more zwitterionic surfactants, one or more amphoteric surfactants, one or more anionic surfactants, and combinations thereof.
    Type: Application
    Filed: October 30, 2008
    Publication date: March 12, 2009
    Inventors: Manilal S. Dahanayake, Bruno Langlois, Paul-Joel Derian, Jean-Pierre Marchand
  • Publication number: 20090065205
    Abstract: There is a method for enhancing the recovery of oil from a reservoir. The method has the step of a) introducing a flooding fluid into the reservoir and b) extracting the oil through a wellbore at a location different than the point of introduction of the flooding fluid into the reservoir. The flooding fluid has water and an amount of one or more non-polymeric viscoelastic surfactants sufficient to provide an interfacial surface tension of about 1 mNm or less and a viscosity of about 10 cps or more. The one or more surfactants is selected from the group of one or more cationic surfactants, one or more zwitterionic surfactants, one or more amphoteric surfactants, one or more anionic surfactants, and combinations thereof.
    Type: Application
    Filed: October 30, 2008
    Publication date: March 12, 2009
    Inventors: Manilal S. Dahanayake, Bruno Langlois, Paul-Joel Derian, Jean-Pierre Marchand
  • Publication number: 20090065203
    Abstract: There is a method for enhancing the recovery of oil from a reservoir. The method has the step of a) introducing a flooding fluid into the reservoir and b) extracting the oil through a wellbore at a location different than the point of introduction of the flooding fluid into the reservoir. The flooding fluid has water and an amount of one or more non-polymeric viscoelastic surfactants sufficient to provide an interfacial surface tension of about 1 mNm or less and a viscosity of about 10 cps or more. The one or more surfactants is selected from the group of one or more cationic surfactants, one or more zwitterionic surfactants, one or more amphoteric surfactants, one or more anionic surfactants, and combinations thereof.
    Type: Application
    Filed: October 30, 2008
    Publication date: March 12, 2009
    Inventors: Manilal S. Dahanayake, Bruno Langlois, Paul-Joel Derian, Jean-Pierre Marchand
  • Publication number: 20090056943
    Abstract: There is a method for enhancing the recovery of oil from a reservoir. The method has the step of a) introducing a flooding fluid into the reservoir and b) extracting the oil through a wellbore at a location different than the point of introduction of the flooding fluid into the reservoir. The flooding fluid has water and an amount of one or more non-polymeric viscoelastic surfactants sufficient to provide an interfacial surface tension of about 1 mNm or less and a viscosity of about 10 cps or more. The one or more surfactants is selected from the group of one or more cationic surfactants, one or more zwitterionic surfactants, one or more amphoteric surfactants, one or more anionic surfactants, and combinations thereof.
    Type: Application
    Filed: October 30, 2008
    Publication date: March 5, 2009
    Inventors: Manilal S. Dahanayake, Bruno Langlois, Paul-Joel Derian, Jean-Pierre Marchand
  • Publication number: 20090056942
    Abstract: There is a method for enhancing the recovery of oil from a reservoir. The method has the step of a) introducing a flooding fluid into the reservoir and b) extracting the oil through a wellbore at a location different than the point of introduction of the flooding fluid into the reservoir. The flooding fluid has water and an amount of one or more non-polymeric viscoelastic surfactants sufficient to provide an interfacial surface tension of about 1 mNm or less and a viscosity of about 10 cps or more. The one or more surfactants is selected from the group of one or more cationic surfactants, one or more zwitterionic surfactants, one or more amphoteric surfactants, one or more anionic surfactants, and combinations thereof.
    Type: Application
    Filed: October 30, 2008
    Publication date: March 5, 2009
    Inventors: Manilal S. Dahanayake, Bruno Langlois, Paul-Joel Derian, Jean-Pierre Marchand
  • Patent number: 7461694
    Abstract: There is a method for enhancing the recovery of oil from a reservoir. The method has the step of a) introducing a flooding fluid into the reservoir and b) extracting the oil through a wellbore at a location different than the point of introduction of the flooding fluid into the reservoir. The flooding fluid has water and an amount of one or more non-polymeric viscoelastic surfactants sufficient to provide an interfacial surface tension of about 1 mNm or less and a viscosity of about 10 cps or more. The one or more surfactants is selected from the group of one or more cationic surfactants, one or more zwitterionic surfactants, one or more amphoteric surfactants, one or more anionic surfactants, and combinations thereof.
    Type: Grant
    Filed: November 16, 2005
    Date of Patent: December 9, 2008
    Assignee: Rhodia Inc.
    Inventors: Manilal S. Dahanayake, Bruno Langlois, Paul-Joel Derian
  • Publication number: 20080200351
    Abstract: A method of fracturing a subterranean zone penetrated by a well bore preparing a foamed fracturing fluid containing a self-degrading foaming composition with a mixture of anionic surfactant and nonionic surfactant, and a composition thereof. The fracturing fluid containing self-degrading foaming composition forms a substantially less stable foam when the foamed fracturing fluid is recovered during reclaim.
    Type: Application
    Filed: April 21, 2008
    Publication date: August 21, 2008
    Inventors: Manilal S. Dahanayake, Subramanian Kesavan, Allwyn Colaco
  • Patent number: 7404442
    Abstract: A method of fracturing a subterranean zone penetrated by a well bore by preparing a foamed fracturing fluid containing a self-degrading foaming composition comprised of a mixture of anionic surfactant and nonionic surfactant. The fracturing fluid containing a self-degrading foaming composition forms a substantially less stable foam when the foamed fracturing fluid is recovered during reclaim.
    Type: Grant
    Filed: April 6, 2006
    Date of Patent: July 29, 2008
    Assignee: Rhodia Inc.
    Inventors: Manilal S. Dahanayake, Subramanian Kesavan, Allwyn Colaco
  • Patent number: 7279446
    Abstract: A method of treating a subterranean formation by injecting down a well an aqueous fluid containing a viscoelastic surfactant fluid comprising an enhanced shear recovery agent wherein shear recovery time of the viscoelastic surfactant fluid is reduced by the addition of the enhanced shear recovery agent, and a viscoelastic surfactant fluid composition thereof.
    Type: Grant
    Filed: November 14, 2005
    Date of Patent: October 9, 2007
    Assignees: Rhodia Inc., Schlumberger Technology Corporation
    Inventors: Allwyn Colaco, Jean-Pierre Marchand, Fang Li, Manilal S. Dahanayake
  • Patent number: 6831108
    Abstract: Viscoelastic surfactant based aqueous fluid systems useful as thickening agents in various applications, e.g. to suspend particles produced during the excavation of geologic formations. The surfactants are zwitterionic/amphoteric surfactants such as dihydroxyl alkyl glycinate, alkyl ampho acetate or propionate, alkyl betaine, alkyl amidopropyl betaine and alkylimino mono- or di-propionates derived from certain waxes, fats and oils. The thickening agent is used in conjunction with an inorganic water-soluble salt or organic additive such as phthalic acid, salicylic acid or their salts.
    Type: Grant
    Filed: July 6, 2001
    Date of Patent: December 14, 2004
    Assignee: Rhodia, Inc.
    Inventors: Manilal S. Dahanayake, Jiang Yang, Joseph H. Y. Niu, Paul Joel Derian, Ruoxin Li, David Dino
  • Patent number: 6476168
    Abstract: Disclosed is an emulsion useful in an inversion process. The emulsion is a water-in-oil emulsion and has an aqueous phase having a water-soluble polymer, an oil phase and an activating agent of the following formula: wherein n=0 to 10 and m=2 to 25 and the oxypropylene and oxyethylene units are of block distribution or intermixed in random or tapered distribution. Further disclosed is a process according to the following: a) providing an water-in-oil emulsion having a water-soluble polymer in the aqueous phase and the activating agent; b) introducing the emulsion into an aqueous medium and c) allowing sufficient time for the emulsion to invert. Further disclosed is another process according to the following: a) providing an water-in-oil emulsion having a water-soluble polymer in the aqueous phase; b) introducing the emulsion into an aqueous medium having the activating agent and c) allowing sufficient time for the emulsion to invert.
    Type: Grant
    Filed: September 14, 2001
    Date of Patent: November 5, 2002
    Assignee: Rhodia, Inc.
    Inventors: Manilal S. Dahanayake, Fang Li, Jean-Luc Joye
  • Patent number: 6358914
    Abstract: Compositions are disclosed comprising a conventional surfactant, a cationic or amphoteric gemini surfactant and a polymeric soil release agent. The conventional surfactant comprises a hydrophilic group and a hydrophobic group. The gemini surfactant comprises two surfactant moieties attached to each other by a spacer moiety. Each surfactant moiety having at least one hydrophilic group and at least one hydrophobic group. Novel trimeric and tetrameric cationic gemini surfactants are also disclosed along with their use in combination with soil release polymer compositions that exhibit superior cleaning efficacies when incorporated in laundry and other cleaning detergent systems. Novel surfactant/soil release polymer compositions are also disclosed employing known cationic gemini surfactants. The polymeric soil release agent can be any conventional polymeric soil release agent, but preferably comprising PET—POET copolymer.
    Type: Grant
    Filed: June 17, 1999
    Date of Patent: March 19, 2002
    Inventors: Gladys S. Gabriel, Robert Gabriel, Manilal S. Dahanayake, Paul-Joel Derian
  • Patent number: 6277801
    Abstract: Highly alkaline caustic cleaners used in large scale industrial applications are stabilized and enhanced with improved surface tension reduction and decreased foaming properties through the incorporation of minor amounts of a surfactant composition comprising a alkylether hydroxypropyl sultaine surfactant and a nonionic ethoxylated surfactant.
    Type: Grant
    Filed: October 4, 1999
    Date of Patent: August 21, 2001
    Assignee: Rhodia Inc.
    Inventors: Manilal S. Dahanayake, Mark E. Ventura
  • Patent number: 6242404
    Abstract: An improved soil release polymer composition comprising a soil release polymer and a long chain nonionic alkoxylate surfactant and/or amphoteric that is able to generate very low critical micelle concentration values in water. Preferably, the soil release composition is incorporated in a detergent system such as a commercial laundry detergent which comprises a second anionic, nonionic or cationic surfactant and mixtures thereof. By lowering the cmc values of the detergent wash water to very low levels, the surfactant greatly enhances the performance of the soil release polymer.
    Type: Grant
    Filed: August 25, 1997
    Date of Patent: June 5, 2001
    Assignee: Rhodia Inc.
    Inventors: Manilal S. Dahanayake, Gladys S. Gabriel, Ronald Brady Bell, Paul Joel Derian, Robert Gabriel
  • Patent number: 6235149
    Abstract: An improved method for inhibiting the deposition of adhesive contaminants, hot melts and/or pressure sensitive adhesive materials onto the surfaces of secondary paper products and repulping equipment during the manufacture of same from waste paper products comprises the application of a water-soluble dispersant selected from the group consisting of a hydrophobically modified hydrocolloid or an acrylic acid polymer. The dispersant, preferably a modified guar gum or sodium acrylic acid/maleic acid copolymer improves product quality and papermaking equipment performance.
    Type: Grant
    Filed: October 7, 1998
    Date of Patent: May 22, 2001
    Assignee: Vinings Industries, Inc.
    Inventors: Manilal S. Dahanayake, Jiang Yang
  • Patent number: 6207058
    Abstract: Contaminated aqueous systems can be cleaned using an ultra-filtration system that allows for high recovery yields of the surfactant employed therein for recycle and reuse. The system employs specific alcohol alkoxylate nonionic surfactants which remain polar and solvated at the higher operating temperatures of the system. The surfactant/contaminant containing aqueous system is ultra-filtered resulting in the surfactant passing through with the permeate at extremely high yields for recovery and reuse.
    Type: Grant
    Filed: July 30, 1999
    Date of Patent: March 27, 2001
    Assignee: Rhodia, Inc.
    Inventors: Mark E. Ventura, Manilal S. Dahanayake
  • Patent number: 6204297
    Abstract: Novel nonionic gemini surfactants are extremely effective emulsifiers for oil-in-water emulsions that provide improved detergency at even low concentration levels. The surfactants are characterized by the formula: wherein R1 is independently H or a C1 to C22 alkyl, R2 is H or C1 to C22 alkyl and R3 is D1—R4—D1 or R4—D1—R4 wherein R4 is independently a C1-C10 alkyl group, —C(O)—, —R5[O(EO)a(PO)b]—, —O—R5—O—, or aryl, e.g. phenyl, and D1 is independently —O—, —S—, —S—S—, —SO2—, —C(O)—, a polyether group [—O(EO)a(PO)b—], an amide group [—C(O)N(R6)—], an amino group [—N(R6)—], —O—R5—O—, or aryl.
    Type: Grant
    Filed: November 26, 1996
    Date of Patent: March 20, 2001
    Assignee: Rhodia Inc.
    Inventors: David James Tracy, Ruoxin Li, Manilal S. Dahanayake, Jiang Yang
  • Patent number: 6121222
    Abstract: A novel class of anionic surfactants with improved surfact active properties is comprised of two hydrophilic and two hydrophobic groups represented by the formula: ##STR1## The surfactants exhibit unusually low critical micelle concentration (cmc) and pC-20 values in aqueous media.
    Type: Grant
    Filed: December 27, 1996
    Date of Patent: September 19, 2000
    Assignee: Rhodia Inc.
    Inventors: Ruoxin Li, David James Tracy, Jiang Yang, Manilal S. Dahanayake
  • Patent number: 6013185
    Abstract: Contaminated aqueous systems can be cleaned using an ultra-filtration system that allows for high recovery yields of the surfactant employed therein for recycle and reuse. The system employs specific nonionic surfactants which remain polar and solvated at the higher operating temperatures of the system. The surfactant/contaminant containing aqueous system is ultra-filtered resulting in the surfactant passing through with the permeate at extremely high yields for recovery and reuse.
    Type: Grant
    Filed: September 25, 1997
    Date of Patent: January 11, 2000
    Assignee: Rhodia Inc.
    Inventors: Mark E. Ventura, Manilal S. Dahanayake