Patents by Inventor Stephen John Evans

Stephen John Evans 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: 9499456
    Abstract: A process for the tetramerisation of ethylene under solution phase conditions is carried out in the presence of an activated catalyst at a temperature above 80° C. and up to a temperature of about 115° C. The activated catalyst is provided by combining a source of chromium, a diphosphine ligating compound and optionally a catalyst activator or combination of catalyst activators. The process forms at least 30% 1-octene and a polyethylene co-product that, together with any other reaction products, remains substantially dissolved in the liquid phase. The polyethylene co-product has a weight average molecular weight (Mw) of less than 200 000 g/mol, a number average molecular weight (Mn) of less than 3 000 g/mol, and a melt flow index of more than 20 g/10 minutes.
    Type: Grant
    Filed: May 8, 2013
    Date of Patent: November 22, 2016
    Assignee: SASOL TECHNOLOGY (PROPRIETARY) LIMITED
    Inventors: Matthew James Overett, Elzet Grobler, Stephen John Evans, Kevin Blann
  • Patent number: 9447202
    Abstract: A process for oligomerization of an olefinic compound for producing an oligomeric product is carried out in the presence of an activated catalyst, a non-metal oxygen containing additive and optionally a zinc compound. The oligomerization catalyst is an activated catalyst, which is provided by combining a source of chromium, a ligating compound, and a catalyst activator or combination of catalyst activators. The non-metal oxygen containing additive is present in an amount such that the ratio of the molar amount of the non-metal oxygen containing additive to the molar amount of chromium in the source of chromium per 106 g/g Cr productivity is between 0.01 and 400.
    Type: Grant
    Filed: May 8, 2013
    Date of Patent: September 20, 2016
    Assignee: SASOL TECHNOLOGY (PROPRIETARY) LIMITED
    Inventors: Martin John Hanton, David Matthew Smith, William Fullard Gabrielli, Stephen John Evans
  • Patent number: 9399179
    Abstract: A process (10) to separate a multi-component hydrocarbon stream (26) comprising ethylene, at least one polymer and other components includes flashing the multi-component hydrocarbon stream in a first flash stage (12) from an elevated pressure of more than 30 bar(a) and an elevated temperature in the range of 150° C. to 135° C. to a flash pressure in the range of 10 bar(a) to 30 bar(a), producing a first ethylene-containing vapor overheads product (28) at a pressure in the range of 10 bar(a) to 30 bar(a) and a first flash stage bottoms product (30.1) which includes some ethylene, the at least one polymer and some of the other components. The flash pressure and the elevated temperature of the multi-component hydrocarbon stream (26) are selected such that the first flash stage bottoms product (30.1) has a concentration of the at least one polymer of less than 5% by mass to render the viscosity of the first flash stage bottoms product (30.1) at the temperature of the first flash stage bottoms product (30.
    Type: Grant
    Filed: May 8, 2013
    Date of Patent: July 26, 2016
    Assignee: SASOL TECHNOLOGY PROPRIETARY LIMITED
    Inventors: Denise Louisette Venter, Natasha Brigman, Tyrone McKnight, Kevin Blann, Stephen John Evans
  • Publication number: 20150152200
    Abstract: A process for oligomerisation of an olefinic compound for producing an oligomeric product is carried out in the presence of an activated catalyst, a non-metal oxygen containing additive and optionally a zinc compound. The oligomerisation catalyst is an activated catalyst, which is provided by combining a source of chromium, a ligating compound, and a catalyst activator or combination of catalyst activators. The non-metal oxygen containing additive is present in an amount such that the ratio of the molar amount of the non-metal oxygen containing additive to the molar amount of chromium in the source of chromium per 106 g/g Cr productivity is between 0.01 and 400.
    Type: Application
    Filed: May 8, 2013
    Publication date: June 4, 2015
    Inventors: Martin John Hanton, David Matthew Smith, William Fullard Gabrielli, Stephen John Evans
  • Patent number: 9035119
    Abstract: This invention relates to the oligomerization of olefinic compounds in the presence of an activated oligomerization catalyst. The invention also extends to a particular manner for providing an activated oligomerization catalyst.
    Type: Grant
    Filed: February 15, 2010
    Date of Patent: May 19, 2015
    Assignee: Sasol Technology (PTY) Limited
    Inventors: Sean William Ewart, Brian William Stirling Kolthammer, David Matthew Smith, Martin John Hanton, John Thomas Dixon, David Hedley Morgan, Henriette De Bod, William Fullard Gabrielli, Stephen John Evans
  • Publication number: 20150133707
    Abstract: A process (10) to separate a multi-component hydrocarbon stream (26) comprising ethylene, at least one polymer and other components includes flashing the multi-component hydrocarbon stream in a first flash stage (12) from an elevated pressure of more than 30 bar(a) and an elevated temperature in the range of 150° C. to 185° C. to a flash pressure in the range of 10 bar(a) to 30 bar(a), producing a first ethylene-containing vapour overheads product (28) at a pressure in the range of 10 bar(a) to 30 bar(a) and a first flash stage bottoms product (30.1) which includes some ethylene, the at least one polymer and some of the other components. The flash pressure and the elevated temperature of the multi-component hydrocarbon stream (26) are selected such that the first flash stage bottoms product (30.1) has a concentration of the at least one polymer of less than 5% by mass to render the viscosity of the first flash stage bottoms product (30.1) at the temperature of the first flash stage bottoms product (30.
    Type: Application
    Filed: May 8, 2013
    Publication date: May 14, 2015
    Inventors: Denise Louisette Venter, Natasha Brigman, Tyrone Mcknight, Kevin Blann, Stephen John Evans
  • Publication number: 20150080629
    Abstract: A process for the tetramerisation of ethylene under solution phase conditions is carried out in the presence of an activated catalyst at a temperature above 80° C. and up to a temperature of about 115° C. The activated catalyst is provided by combining a source of chromium, a diphosphine ligating compound and optionally a catalyst activator or combination of catalyst activators. The process forms at least 30% 1-octene and a polyethylene co-product that, together with any other reaction products, remains substantially dissolved in the liquid phase. The polyethylene co-product has a weight average molecular weight (Mw) of less than 200 000 g/mol, a number average molecular weight (Mn) of less than 3 000 g/mol, and a melt flow index of more than 20 g/10 minutes.
    Type: Application
    Filed: May 8, 2013
    Publication date: March 19, 2015
    Inventors: Matthew James Overett, Elzet Grobler, Stephen John Evans, Kevin Blann
  • Publication number: 20120041241
    Abstract: This invention relates to the oligomerisation of olefinic compounds in the presence of an activated oligomerisation catalyst. The invention also extends to a particular manner for providing an activated oligomerisation catalyst.
    Type: Application
    Filed: February 15, 2010
    Publication date: February 16, 2012
    Inventors: Sean William Ewart, Brian William Stiring Kolthammer, David Matthew Smith, Martin John Hanton, John Thomas Dixon, David Hedley Morgan, Henriette De Bod, William Fullard Gabrielli, Stephen John Evans