Patents by Inventor Ramakrishnan Ramachandran

Ramakrishnan Ramachandran 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: 5177225
    Abstract: Disclosed is a process for the production of an alkylene oxide in which an alkene, and an oxygen containing gas are reacted in the presence of a flame suppressor under conditions of low alkene conversion and high alkylene oxide selectivity in which unreacted alkene is recycled to the reactor and there is efficient removal of nitrogen and carbon dioxide.
    Type: Grant
    Filed: July 9, 1990
    Date of Patent: January 5, 1993
    Assignee: The BOC Group, Inc.
    Inventors: Ramakrishnan Ramachandran, Donald L. MacLean
  • Patent number: 5126463
    Abstract: This invention provides a process for the production of an anhydride by the vapor phase reaction of a hydrocarbon with substantially pure oxygen in the presence of a suitable catalyst. In the improved process, the anhydride product is removed, carbon monoxide, present in the reactor effluent as a by-product, is oxidized to carbon dioxide and part of the gaseous effluent, comprised mainly of carbon dioxide and unreacted hydrocarbon, is recycled to the reactor. Removal of carbon monoxide from the recycle stream reduces the hazard of a fire or explosion in the reactor or associated equipment. The use of carbon dioxide as the principal diluent increases heat removal from the reactor, thereby increasing the production capacity of the reactor.
    Type: Grant
    Filed: October 31, 1990
    Date of Patent: June 30, 1992
    Assignee: The BOC Group, Inc.
    Inventors: Ramakrishnan Ramachandran, Arthur I. Shirley, Lien-Lung Sheu
  • Patent number: 5043461
    Abstract: An improved process for the production of oxides from hydrocarbons by reaction with oxygen, air or a gas enriched in oxygen relative to air, preferably the latter, in the presence of a suitable catalyst. An alkane, e.g. propane, is converted to an alkene in a catalytic dehydrogenator. The product stream is introduced into an oxidation reactor. Product formed therein is recovered in a conventional quench tower. The pressure of the gaseous effluent from the quench tower is raised and it is introduced into an absorber/stripper unit to form a recycle stream containing unreacted alkane and alkene as well as a minor amount of oxygen, typically 1-2 percent by volume, and a waste stream comprising the remainder of the quench tower gaseous phase. The recycle stream enters a selective oxidation unit wherein oxygen is removed, and the product recycled to the dehydrogenator.
    Type: Grant
    Filed: May 3, 1990
    Date of Patent: August 27, 1991
    Assignee: The BOC Group, Inc.
    Inventors: Ramakrishnan Ramachandran, Mark J. Andrecovich, Donald L. MacLean, Donald P. Satchell, Jr.
  • Patent number: 5015756
    Abstract: An improved process is provided for the production of nitriles from hydrocarbons by reaction with an oxygen-containing gas comprising oxygen, air or a gas enriched in oxygen relative to air and ammonia in the presence of a suitable catalyst. In the process, a selective separator provides recycle of a substantial portion of the unreacted hydrocarbon as well as for a controlled amount of a gaseous flame suppressor in the system. The gaseous flame suppressor comprises a substantially unreactive hydrocarbon containing 1 to 5 carbon atoms, carbon dioxide and nitrogen when present in the feed to the ammoxidation reactor. The use of air or oxygen-enriched air in the feed to the ammoxidation reactor is particularly advantageous from an economic view in combination with a pressure swing adsorption unit as the selective separator. The process is characterized by high selectivity to the formation of the product.
    Type: Grant
    Filed: May 1, 1989
    Date of Patent: May 14, 1991
    Assignee: The BOC Group, Inc.
    Inventors: Ramakrishnan Ramachandran, Yagya Shukla, Donald L. MacLean
  • Patent number: 5008414
    Abstract: An improved process is provided for the production of oxides from hydrocarbons by reaction with oxygen, air or a gas enriched in oxygen relative to air, preferably the latter in the presence of an oxidation catalyst. An alkane, e.g. propane, is converted to an alkene in a catalytic dehydrogenator. The product stream is introduced into an oxidation reactor. The product formed therein is recovered in a conventional quench tower. The gaseous effluent from the quench tower is treated in a separator to produce an adsorbed stream, an oxygen-enriched stream, a waste stream and, if desired, a hydrogen-enriched stream. The oxygen-enriched stream may be recycled to the oxidation reactor depending on the nitrogen content thereof. The adsorbed stream plus at least a portion of the hydrogen-enriched stream is introduced into a selective oxidation unit to remove the remaining oxygen and then recycled to the dehydrogenator. The remainder of the hydrogen-enriched stream, if any, may be taken as product or vented.
    Type: Grant
    Filed: September 21, 1989
    Date of Patent: April 16, 1991
    Assignee: The BOC Group, Inc.
    Inventors: Ramakrishnan Ramachandran, Donald L. MacLean, Donald P. Satchell, Jr., Virginia A. Malik
  • Patent number: 5008412
    Abstract: An improved process is provided for the production of oxides from alkanes by reaction with oxygen, air or a gas enriched in oxygen relative to an air in the presence of an oxidation catalyst. An alkane, e.g. propane, is converted to an alkene in a multistage dehydrogenator. The product stream is withdrawn from an intermediate reactor in the dehydrogenator, other than the first and the last reactor, and introduced into an oxidation reactor. The product formed in the oxidation reactor is recovered in a conventional quench tower. The gaseous effluent from the quench tower is treated in a pressure swing adsorption (PSA) unit to form a gaseous stream containing the unreacted alkane and alkene as well as a minor amount, i.e. less than about 2 percent by volume, of oxygen and nitrogen, if present in the feed to the oxidation reactor.
    Type: Grant
    Filed: July 6, 1989
    Date of Patent: April 16, 1991
    Assignee: The BOC Group, Inc.
    Inventors: Ramakrishnan Ramachandran, Donald L. MacLean, Donald P. Satchell, Jr.
  • Patent number: 4990632
    Abstract: An improved process is provided for the production of oxides from hydrocarbons by reaction with oxygen, air or a gas enriched in oxygen relative to air, preferably the latter, in the presence of an oxidation catalyst. An alkane, e.g. propane, is converted to an alkene in a dehydrogenator. The product stream is introduced into an oxidation reactor. The product formed therein is recovered in a quench tower. The gas phase from the quench tower is treated in a PSA unit to form a gaseous stream containing the unreacted alkane, alkene, a minor amount of oxygen, i.e. less than about 2 percent by volume, and nitrogen if present in the feed to the oxidation reactor. The gaseous stream, which may or may not contain hydrogen depending on the adsorbent on the PSA unit, is introduced into a selective oxidation unit to remove the remaining oxygen and then recycled to the dehydrogenator.
    Type: Grant
    Filed: July 6, 1989
    Date of Patent: February 5, 1991
    Assignee: The BOC Group, Inc.
    Inventors: Ramakrishnan Ramachandran, Donald L. Maclean, Donald P. Satchell, Jr.
  • Patent number: 4987239
    Abstract: An improved process is provided for the production of anhydrides from hydrocarbons by reaction with an oxygen-containing gas comprising oxygen, air or a gas enriched in oxygen relative to air, in the presence of a suitable catalyst. In the process, a selective separator provides recycle of a substantial portion of the unreacted hydrocarbon as well as for a controlled amount of a gaseous flame suppressor in the system. The gaseous flame suppressor comprises a substantially unreactive hydrocarbon containing 1 to 5 carbon atoms, carbon dioxide, and nitrogen when present in the feed to the oxidation reactor. The use of air or oxygen-enriched air in the feed to the oxidation reactor is particularly advantageous from an economic view in combination with a pressure swing adsorption unit as the selective separator. The process is characterized by high selectively to the formation of the anhydride product.
    Type: Grant
    Filed: May 24, 1989
    Date of Patent: January 22, 1991
    Assignee: The BOC Group, Inc.
    Inventors: Ramakrishnan Ramachandran, Yagya Shukla, Donald L. MacLean
  • Patent number: 4943650
    Abstract: An improved process is provided for the production of nitriles and oxides from hydrocarbons by reaction with oxygen, air or a gas enriched in oxygen relative to air, preferably the latter, and ammonia where a nitrile is desired, in the presence of a suitable catalyst. An alkane, e.g. propane, is converted to an alkene in a catalytic dehydrogenator. The product stream is introduced into an ammoxidation reactor. The product formed therein is recovered in a conventional quench tower. The pressure of the gaseous effluent from the quench tower is raised and it is introduced into an absorber/stripper unit to form a recycle stream containing unreacted alkane and alkene as well as a minor amount of oxygen, typically 1-2 percent by volume, and a waste stream comprising the remainder of the quench tower gaseous phase. The recycle stream is introduced into a selective oxidation unit to remove the oxygen therefrom and then recycled to the dehydrogenator.
    Type: Grant
    Filed: January 30, 1989
    Date of Patent: July 24, 1990
    Assignee: The BOC Group, Inc.
    Inventors: Ramakrishnan Ramachandran, Mark J. Andrecovich, Donald L. MacLean, Donald P. Satchell, Jr.
  • Patent number: 4870201
    Abstract: An improved process is provided for the production of nitriles from hydrocarbons by reaction with oxygen, air or a gas enriched in oxygen relative to air, preferably the latter, and ammonia in the presence of an ammoxidation catalyst. An alkane, e.g., propane, is converted to an alkene in a catalytic dehydrogenator. The product stream is introduced into an ammoxidation reactor. The product formed therein is recovered in a conventional quench tower. The gaseous effluent from the quench tower is treated in a PSA unit comprising at least two pairs of adsorptive beds. The first bed forms a gas stream containing the unreacted alkane and alkene as well as a minor amount, typically 1-2 percent by volume, of oxygen and a vent stream containing oxygen, nitrogen if present, and hydrogen. The vent stream is introduced into the second adsorptive bed to thereby form an oxygen-containing stream which also contains, nitrogen, if present, and a hydrogen-enriched stream.
    Type: Grant
    Filed: December 8, 1988
    Date of Patent: September 26, 1989
    Assignee: The BOC Group, Inc.
    Inventors: Ramakrishnan Ramachandran, Virginia A. Malik, Donald L. MacLean, Donald P. Satchell, Jr.
  • Patent number: 4868330
    Abstract: An improved process is provided for the production of nitriles from hydrocarbons by reaction with an oxygen-containing gas comprising oxygen, air or a gas enriched in oxygen relative to air and ammonia in the presence of a suitable catalyst. In the process, a selective separator provides recycle of a substantial portion of the unreacted hydrocarbon as well as for a controlled amount of a gaseous flame suppressor in the system. The gaseous flame suppressor comprises a substantially unreactive hydrocarbon containing 1 to 5 carbon atoms, carbon dioxide and nitrogen when present in the feed to the ammoxidation reactor. The use of air or oxygen-enriched air in the feed to the ammoxidation reactor is particularly advantageous from an economic view in combination with a pressure swing adsorption unit as the selective separator. The process is characterized by high selectivity to the formation of the product.
    Type: Grant
    Filed: July 7, 1988
    Date of Patent: September 19, 1989
    Assignee: The BOC Group, Inc.
    Inventors: Ramakrishnan Ramachandran, Yagya Shukla, Donald L. MacLean
  • Patent number: 4849538
    Abstract: An improved process is provided for the production of nitriles from hydrocarbons by reaction with oxygen, air or a gas enriched in oxygen relative to air, preferably the latter, and ammonia in the presence of an ammoxidation catalyst. An alkane, e.g. propane, is converted to an alkene in a dehydrogenator. The product stream is introduced into an ammoxidation reactor. The product formed therein is recovered in a conventional quench tower. The gaseous effluent from the quench tower is treated in a PSA unit to form a gas stream containing the unreacted alkane and alkene as well as a minor amount, i.e. less than about 1 percent by volume, of oxygen and nitrogen, if present in the feed to the ammoxidation reactor. The gas stream, which may or may not contain hydrogen depending on the absorbent in the PSA unit, is introduced into a selective oxidation unit to remove the remaining oxygen and then recycled to the dehydrogenator.
    Type: Grant
    Filed: July 6, 1988
    Date of Patent: July 18, 1989
    Assignee: The BOC Group, Inc.
    Inventors: Ramakrishnan Ramachandran, Donald L. MacLean, Donald P. Satchell, Jr.
  • Patent number: 4849537
    Abstract: An improved process is provided for the production of nitriles from hydrocarbons by reaction with oxygen, air or gas-enriched in relative to an air, and ammonia, in the presence of an ammoxidation catalyst. An alkane, e.g. propane, is converted to an alkene in a multistage dehydrogenator. The product stream is withdrawn from a reactor in the dehydrogenator other than the first and the last reactor and introduced into an ammoxidation reactor. The product is recovered in a conventional quench tower. The gaseous effluent from the quench tower is treated in a pressure swing adsorption unit to form a gas stream containing the unreacted alkane and alkene as well as a minor amount of oxygen. The gas stream, which may or may not contain hydrogen depending on the absorbent in the pressure swing adsorption unit, is introduced into the reactor in the dehydrogenator following that from which the product stream was withdrawn.
    Type: Grant
    Filed: July 6, 1988
    Date of Patent: July 18, 1989
    Assignee: The BOC Group, Inc.
    Inventors: Ramakrishnan Ramachandran, Donald L. MacLean, Donald P. Satchell, Jr.