Patents by Inventor Dilum D. Dunuwila

Dilum D. Dunuwila 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).

  • Patent number: 6846431
    Abstract: A liquid antifreeze which is produced from renewable resources, and which is biodegradable, non-toxic, and is non-corrosive to engines is provided. The liquid antifreeze composition for use as an engine coolant in a dilute or concentrate form comprises a water soluble salt of succinic acid, a water soluble salt of acetic acid, ethanol, and water, wherein the composition has a freezing point of greater than ?30° C. in the engine. A method for cooling an engine with a cooling system which comprises the coolant compositions is also provided.
    Type: Grant
    Filed: December 26, 2003
    Date of Patent: January 25, 2005
    Assignee: Diversified Natural Products, Inc.
    Inventors: Dilum D. Dunuwila, Kris A. Berglund
  • Publication number: 20030197150
    Abstract: Deicing and anti-icing compositions comprising a succinate salt and at least one freezing point depressant selected from the group consisting of monohydric alcohols, polyhydric alcohols, monomethyl or monoethyl ethers of polyhydric alcohols, and mixtures thereof. The compositions have enhanced ice-melting capacity compared to the ice-melting capacity of the succinate salt or the alcohol alone, particularly at temperatures below about −10° C. The compositions are particularly useful as a windshield deicer/washer. Particular embodiments of the compositions are environmentally friendly.
    Type: Application
    Filed: April 18, 2002
    Publication date: October 23, 2003
    Applicants: Board of Trustees of Michigan State University, Applied CarboChemicals
    Inventors: Kris A. Berglund, Dilum D. Dunuwila, Hasan Alizadeh
  • Patent number: 6635188
    Abstract: Deicing and anti-icing compositions comprising a succinate salt and at least one freezing point depressant selected from the group consisting of monohydric alcohols, polyhydric alcohols, monomethyl or monoethyl ethers of polyhydric alcohols, and mixtures thereof. The compositions have enhanced ice-melting capacity compared to the ice-melting capacity of the succinate salt or the alcohol alone, particularly at temperatures below about −10° C. The compositions are particularly useful as a windshield deicer/washer. Particular embodiments of the compositions are environmentally friendly.
    Type: Grant
    Filed: April 18, 2002
    Date of Patent: October 21, 2003
    Assignees: Board of Trustees of Michigan State University, Applied CarboChemicals
    Inventors: Kris A. Berglund, Dilum D. Dunuwila, Hasan Alizadeh
  • Patent number: 6623657
    Abstract: Deicing compositions are provided for removing ice from a surface which include either succinic acid or succinic anhydride, or both, and a neutralizing base such as sodium hydroxide, potassium hydroxide, or ammonium hydroxide wherein the deicing compositions when mixed with water produce succinate salts in a reaction that rapidly releases sufficient heat to melt the ice on the surface and the succinate salts act as a deicer and freezing point depressant. In particular embodiments, the deicing compositions further include a glycol which inhibits reformation of the ice on the deiced surface. The deicing compositions are suitable and effective for airport applications in which corrosion of aircraft alloys and concrete runways are of concern.
    Type: Grant
    Filed: April 18, 2002
    Date of Patent: September 23, 2003
    Assignee: Board of Trustees of Michigan State University
    Inventors: Kris A. Berglund, Dilum D. Dunuwila, Hasan Alizadeh
  • Patent number: 6287480
    Abstract: Improved deicing compositions and methods are provided. In particular, the subject invention is directed at deicing compositions which are suitable and effective for airport applications in which corrosion of magnesium based alloys is an issue. In particular, the invention is directed at deicing compositions which are less corrosive of steel and aluminum and certain magnesium based parts than conventional road salt. For example, the invention is directed to deicing compositions which are substantially less corrosive than allowed for use on aircraft metal parts, such as magnesium based alloys unlike acetate and formate salts. The subject invention is also directed at deicing compositions which inhibit the corrosive effects of conventional road salt. The subject invention is also directed at deicing compositions comprising effective deicing amounts of succinate salts, such as potassium succinate (trihydrate), ammonium succinate (anyhdrous), sodium succinate (hexahydrate), either alone or in combination.
    Type: Grant
    Filed: January 11, 2000
    Date of Patent: September 11, 2001
    Assignees: Applied CarboChemicals, Inc., Michigan State University
    Inventors: Kris A. Berglund, Hasan Alizadeh, Dilum D. Dunuwila
  • Patent number: 6265190
    Abstract: A highly efficient process for the production and recovery of pure succinic acid from a succinate salt that involves minimal use of additional reagents, and produces virtually no waste by-products, and permits internal recycle of the base and acid values, is provided. The method involves the formation of diammonium succinate, either by using an ammonium ion based material to maintain neutral8 pH in the fermenter or by substituting the ammonium cation for the cation of the succinate salt created in the fermenter. The diammonium succinate can then be reacted with a sulfate ion, such as by combining the diammonium succinate with ammonium bisulfate and/or sulfuric acid at sufficiently low pH to yield succinic acid and ammonium sulfate. The ammonium sulfate is advantageously cracked thermally into ammonia and ammonium bisulfate. The succinic acid can be purified with a methanol dissolution step. Various filtration, reflux and reutilization steps can also be employed.
    Type: Grant
    Filed: September 2, 1999
    Date of Patent: July 24, 2001
    Assignees: Michigan State University, Applied CarboChemicals, Inc.
    Inventors: Sanjay Yedur, Kris A. Berglund, Dilum D. Dunuwila
  • Patent number: 5958744
    Abstract: A highly efficient process for the production and recovery of pure succinic acid from a succinate salt that involves minimal use of additional reagents, and produces virtually no waste by-products, and permits internal recycle of the base and acid values, is provided. The method involves the formation of diammonium succinate, either by using an ammonium ion based material to maintain neutral8 pH in the fermenter or by substituting the ammonium cation for the cation of the succinate salt created in the fermenter. The diammonium succinate can then be reacted with a sulfate ion, such as by combining the diammonium succinate with ammonium bisulfate and/or sulfuric acid at sufficiently low pH to yield succinic acid and ammonium sulfate. The ammonium sulfate is advantageously cracked thermally into ammonia and ammonium bisulfate. The succinic acid can be purified with a methanol dissolution step. Various filtration, reflux and reutilization steps can also be employed.
    Type: Grant
    Filed: August 13, 1998
    Date of Patent: September 28, 1999
    Assignee: Applied Carbochemicals
    Inventors: Kris A. Berglund, Sanjay Yedur, Dilum D. Dunuwila