Patents by Inventor John S. Rendall

John S. Rendall 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: 20030098262
    Abstract: A method and apparatus for the extraction of hydrocarbon products, alumina and soda ash from oil shales including various amounts of such chemicals, all based on solvent extraction of most of the hydrocarbons at temperatures around 400° C. Such enables the alumina and soda ash values to be leached out with aqueous sodium carbonate leaching at reduced temperatures of around 150° C. with a corresponding reduced pressure. The soda ash monohydrate values are precipitated from the leach liquor at around 100° C. with the alumina values precipitated using Co2. Alternatively recycled fine aluminum trihydrate at 65° C. is used to produce alumina. Aluminum hydroxide is converted to acid alumina by an acid recycle stream that dissolves the alumina so any silica contaminant can be filtered out. Basic aluminum sulfate is then precipitated at about 200° C. and 250 PSIG for subsequent calcination at around 900° C.
    Type: Application
    Filed: September 19, 2002
    Publication date: May 29, 2003
    Inventor: John S. Rendall
  • Patent number: 6447738
    Abstract: A process for the extraction of alumina, iron oxide and titanium dioxide from bauxite ore and clays, and other ore bodies and feedstocks. The process starts by sulfuric acid leaching of the feedstocks in pressure autoclaves at about 200° C. and appropriate pressure. A leach liquor of sulfate salts of aluminum, iron and titanium is obtained. Any iron values are converted to a ferrous state. A recycled potassium sulfate helps produce double aluminum alkali sulfate crystals in the reduced leach liquor. The crystals are removed at about 20°-60° C. with the help of SO2 gases that reduce the ferric. Such double salt is hydrolyzed into a basic aluminum alkali precipitated sulfate salt. This is then dried and calcined at about 950° C. Any alkali sulfate is washed out and recycled. The remainder is alumina. The ferrous sulfate is crystallized out at about 10° C. It is dried and calcined at about 450° C. to produce an iron oxide mixed with other sulfate salts that can be washed out and recycled.
    Type: Grant
    Filed: August 24, 2000
    Date of Patent: September 10, 2002
    Assignee: Solv-Ex Corporation
    Inventors: John S. Rendall, Massoud Ahghar, Jerry V. Fox, Fred A. Aiken
  • Patent number: 6245201
    Abstract: The aluminum smelting from alumina in the Hall-Heroult cells can be dramatically improved by using one or a combination of the following features together or in alternative to the Bayer alumina as feedstock: Al+++ alumina, sawtooth shaped electrodes, and lower temperatures. Laboratory experiments have shown that higher rates of dissolution of the Al+++ alumina in molten fluoride baths combined with lower voltage drops and improved design of electrodes can allow the operation of the cells at even higher current density, thus increasing overall productivity and efficiency of the cells.
    Type: Grant
    Filed: August 3, 1999
    Date of Patent: June 12, 2001
    Inventor: John S. Rendall
  • Patent number: 6221233
    Abstract: The smelting of aluminum from alumina in the Hall-Heroult process can be dramatically improved by lowering power consumption and in the use of carbon free anodes by using a feed of positively charged alumina. Laboratory experiments have shown that the apparent solubility and reactivity of alumina in molten fluoride baths is surprisingly increased by altering the negatively charged aluminum hydroxide Al(OH)4− particles, at about pH of nine, to positively charged particles containing Al+++ with a pH of less than two, by using acid solutions. The alumina thus produced is referred to as Al+++ alumina, or positively charged alumina. In particular, sulfuric acid is used to convert aluminum hydroxide using the Bayer process to a family of basic aluminum sulfates, 3Al2O3.4SO3.9H2O, which are dehydrated and calcined to produce Al+++ alumina.
    Type: Grant
    Filed: March 8, 1999
    Date of Patent: April 24, 2001
    Inventor: John S. Rendall
  • Patent number: 6056813
    Abstract: A process for making white pigment directly from constituent materials without byproducts. The process comprises the steps of inputting three material flows comprising a sulphate source, an alkali source, and an aluminum source. And, recycling and mixing into the three material flows a process return from a separation and wash stage and vapors from a pressure let-down stage. This is followed by heating and holding a mixture of recycled process returns and the three material flows at elevated pressure in a reactor for a minimum predetermined residence time. Afterwards, letting down pressure in a flow from the reactor to produce a pre-wash flow. Then, separating, classifying, and delaminating the pre-wash flow into a first and second pigment or filler that are differentiated by their respective average particle distribution sizes.
    Type: Grant
    Filed: December 14, 1998
    Date of Patent: May 2, 2000
    Assignee: Solv-Ex Corporation
    Inventors: John S. Rendall, Massoud Ahghar, Jerry V. Fox, Fred A. Aiken, III
  • Patent number: 6004455
    Abstract: A sand/liquid separator provides for the conditioning of oil sands. Clean sand is separated from the ore and discharged for use as backfill. The sand/liquid separator machine includes horizontal shafts with paddles that act on a fluidized bed. The overall height of the machine is increased over prior art devices so the water volume is expanded. For a given residence time, more sand can be separated out than is otherwise possible. The water-to-sand ratio is an independent variable, water is recycled independent of the sand. The rate of water recycle depends only on the heat input needed and the clay content of the feed. The rate of water input is limited by the rise velocity needed to separate sand larger than forty-four micron from the water/liquid phase. This, in turn, determines the maximum oil sand feed rate based on the total clay in the feed at up to six percent, by weight, of clay in the middlings in the machine.
    Type: Grant
    Filed: October 8, 1997
    Date of Patent: December 21, 1999
    Inventor: John S. Rendall
  • Patent number: 5997828
    Abstract: A process for extraction of alumina from ore bodies containing aluminum is disclosed. The process comprises the steps of acid leaching an aluminum bearing ore to produce a leach liquor that includes aluminum values and silicon values. Any ferrous sulfate in the leach liquor is oxidized with an oxidizing agent comprising ozone to ferric sulfate. The oxidized leach liquor is hydrolyzed at about 130.degree. C. to form a gel of ferric values which are then removed. Any ferric sulfate remaining in the leach liquor after hydrolyzing is reduced to ferrous sulfate. The reduced leach liquor is then hydrolyzed at 165-180.degree. C. to remove precipitated basic aluminum alkali sulfate. The basic aluminum alkali sulfate is then dried and calcined at around 950.degree. C. to produce alumina and alkali sulfate which releases any SO.sub.2 and any SO.sub.3. The alumina is washed to remove any alkali sulfate and the washed alumina is then agglomerated and dried.
    Type: Grant
    Filed: September 30, 1998
    Date of Patent: December 7, 1999
    Inventor: John S. Rendall
  • Patent number: 5895523
    Abstract: A process is provided for making K.sub.2 SO.sub.4 3Al.sub.2 O.sub.3 4S0.sub.3 +xH.sub.2 O or Na.sub.2 SO.sub.4 3Al.sub.2 O.sub.3 4SO.sub.3 +xH.sub.2 O where x is a number from 4 to 12, which is used as a pigment. Sulfuric acid, one of a sulfate salt or a hydroxide of either potassium or sodium and one of a sulfate of aluminum or a hydroxide of aluminum are inputted into a crystallizer and reacted to form either Al.sub.2 (SO.sub.4).sub.3 K.sub.2 SO.sub.4 +24H.sub.2 O or Al.sub.2 (SO.sub.4).sub.3 Na.sub.2 SO.sub.4 +24H.sub.2 O. A fluid flow containing either Al.sub.2 (SO.sub.4).sub.3 K.sub.2 SO.sub.4 +24H.sub.2 O or Al.sub.2 (SO.sub.4).sub.3 Na.sub.2 SO.sub.4 +24H.sub.2 O is drawn off from the crystallizer and transferred into a pigment reactor where it is subjected to a temperature of about 200.degree. C. and a pressure ranging from 120 to 350 pounds per square inch so as to result in the production of either basic potassium aluminum sulfate K.sub.2 SO.sub.4 3Al.sub.2 O.sub.3 4SO.sub.3 +xH.sub.
    Type: Grant
    Filed: December 24, 1997
    Date of Patent: April 20, 1999
    Assignee: Solv-Ex Corporation
    Inventors: John S. Rendall, Massoud Ahghar, Jerry V. Fox
  • Patent number: 5871571
    Abstract: A process for making ink which begins with a leach liquor of Al.sub.2 (SO.sub.4).sub.3 +K.sub.2 SO.sub.4 +Fe.sub.2 SO.sub.4 and other sulfates that are introduced to a surface-cooled crystallizer that drops the Al.sub.2 (SO.sub.4).sub.3 +18H.sub.2 O which is removed from the leach liquor. The leach liquor is then supplied with a mixture which includes K.sub.2 SO.sub.4 into a simple crystallization and evaporation unit to drop Al.sub.2 (SO.sub.4).sub.3 +K.sub.2 SO.sub.4 +24H.sub.2 O. A pressure of 250 PSI and a temperature of 200.degree. C. are then applied in a discrete continuous process that yield a basic sodium or sodium/potassium aluminum sulfate and excess sodium sulfate or sodium/potassium. The excess sodium sulfate or sodium/potassium sulfate is returned to the simple crystallization and evaporation unit. The basic potassium aluminum sulfate (BKAS) and/or basic sodium aluminum sulfate (BNaAS) Na.sub.2 SO.sub.4, 3Al.sub.2 O.sub.3, 4SO.sub.3, 9H.sub.2 O is used as a filler in the making of ink.
    Type: Grant
    Filed: July 14, 1997
    Date of Patent: February 16, 1999
    Assignee: SOLV-EX Corporation
    Inventors: John S. Rendall, Massoud Ahghar, David H. Fishman
  • Patent number: 5865952
    Abstract: A process in which a leach liquor of Al.sub.2 (SO.sub.4).sub.3 +K.sub.2 SO.sub.4 +Fe.sub.2 SO.sub.4 and other sulphates is introduced to a surface-cooled crystallizer that drops the Al.sub.2 (SO.sub.4).sub.3 +18H.sub.2 O. The leach liquor is pumped through a heat exchanger that keeps a temperature of 160.degree. F. and the surface temperature of the surface-cooled crystallizer is maintained at 60.degree. F. The temperature gradient within the leach liquor promotes crystal formation. These crystals are then supplied to mixture which includes K.sub.2 SO.sub.4 in a simple crystallization and evaporation step that uses a vacuum of twenty inches of mercury and heat to drop Al.sub.2 (SO.sub.4).sub.3 +K.sub.2 SO.sub.4 +24H.sub.2 O. A pressure of 250 PSI and a temperature of 200.degree. C. are then applied in a discrete continuous process that yield a basic sodium or potassium aluminum sulphate and excess sodium sulphate or potassium.
    Type: Grant
    Filed: May 7, 1998
    Date of Patent: February 2, 1999
    Assignee: Solv-Ex Corporation
    Inventors: John S. Rendall, Massoud Ahghar
  • Patent number: 5846512
    Abstract: A method of making activated alumina including the steps of dissolving a double salt of aluminum in a solution of pure water at 85.degree. C., recrystalizing the double salt at a pressure about 250 psi and temperature ranging from 200.degree. C. to 250.degree. C., precipitating out the purified basic double salt, drying the precipitated double salt to drive off water and roasting it at 850.degree. C. to 950.degree. C. to drive off the sulfate, washing to remove the potassium sulfate and then drying the remaining alumina to yield activated alumina for use as a high-grade catalyst.
    Type: Grant
    Filed: December 4, 1996
    Date of Patent: December 8, 1998
    Assignee: Solv-Ex Coporation
    Inventors: John S. Rendall, Massoud Ahghar, Stephen J. Lane
  • Patent number: 5795444
    Abstract: A system and method for immediately separating oil sands into three layers uses a logwasher with paddles that mixes the oil sands with hot water and steam. The three layers of bitumen, clay/sand/water slurry and rock separate effectively and immediately and are not re-mixed in further processing as was conventional, further producing a clay fraction from the fines for mineral processing.
    Type: Grant
    Filed: December 15, 1994
    Date of Patent: August 18, 1998
    Assignee: Solv-Ex Corporation
    Inventors: John S. Rendall, Stephen J. Lane
  • Patent number: 5783163
    Abstract: A process in which a leach liquor of Al.sub.2 (SO.sub.4).sub.3 +K.sub.2 SO.sub.4 +Fe.sub.2 SO.sub.4 and other sulphates is introduced to a surface-cooled crystallizer that drops the Al.sub.2 (SO.sub.4).sub.3 +18H.sub.2 O. The leach liquor is pumped through a heat exchanger that keeps a temperature of 160.degree. F. and the surface temperature of the surface-cooled crystallizer is maintained at 60.degree. F. The temperature gradient within the leach liquor promotes crystal formation. These crystals are then supplied to mixture which includes K.sub.2 SO.sub.4 in a simple crystallization and evaporation step that uses a vacuum of twenty inches of mercury and heat to drop Al.sub.2 (SO.sub.4).sub.3 +K.sub.2 SO.sub.4 +24H.sub.2 O. A pressure of 250 PSI and a temperature of 200.degree. C. are then applied in a discrete continuous process that yield a basic sodium or potassium aluminum sulphate and excess sodium sulphate or potassium.
    Type: Grant
    Filed: August 27, 1996
    Date of Patent: July 21, 1998
    Assignee: Solv-Ex Corporation
    Inventors: John S. Rendall, Massoud Ahghar
  • Patent number: 5783280
    Abstract: An insulation material comprising the double salt of aluminum potassium sulphate and method of producing such. Aluminum sulphate materials and potassium sulphate materials are combined to form aluminum potassium sulphate which is then dehydrated to remove the water of hydration. Porous forms are made by mixing the hydrated aluminum potassium sulphate with a binder before dehydration. The resultant dehydrated sulphate expands greatly to provide an insulative material which is of lightweight and inorganic.
    Type: Grant
    Filed: October 7, 1996
    Date of Patent: July 21, 1998
    Assignee: Solv-Ex Corporation
    Inventors: John S. Rendall, Massoud Ahghar
  • Patent number: 5762780
    Abstract: A system and method for immediately separating oil sands into three layers uses a logwasher with paddles that mixes the oil sands with hot water and steam. The three layers of bitumen, clay/sand/water slurry and rock separate effectively and immediately and are not re-mixed in further processing as was conventional, further producing a clay fraction from the fines for mineral processing.
    Type: Grant
    Filed: April 10, 1996
    Date of Patent: June 9, 1998
    Assignee: Solv-Ex Corporation
    Inventors: John S. Rendall, Stephen J. Lane
  • Patent number: 5746932
    Abstract: A method of making low-density silica-alumina thermal insulation wherein sulfuric acid is used to leach clay fines from processed Athabasca oil sands. The treated fines are dried and roasted to produce a fine buff to white colored powder with particle sizes that range from forty microns to less than a micron. About 80% of these particles are less than twenty microns. The bulk density of this powder is about fifteen to thirty-five pounds to the cubic-foot (lb./ft.sup.3), compared to silica sand which has a bulk density of 150 lb./ft.sup.3, and alumina which is about 200 lb./ft.sup.3, depending on the grade and method of production.
    Type: Grant
    Filed: November 14, 1996
    Date of Patent: May 5, 1998
    Assignee: Solv-Ex Corporation
    Inventors: John S. Rendall, Massoud Ahghar
  • Patent number: 5720868
    Abstract: A method of making activated alumina includes beginning with a leach liquor of potassium and aluminum sulphates that is subjected to a surface-cooled crystallizer with a heat-exchanger input temperature of 160.degree. F. and a surface-chilled temperature of 60.degree. F. Crystals of aluminum sulphate are precipitated and recrystalized by evaporation in a vacuum and at an elevated temperature. Purified crystals of aluminum sulphate are then dried at 50.degree.-60.degree. C. The dried aluminum sulphate crystals are then dehydrated at 400.degree.-450.degree. C. after a rise rate of 50.degree.-60.degree. C. per minute to drive off most of the water. A roasting and recalcination step at 1000.degree. C.-1050.degree. C. after a rise rate of 50.degree.-60.degree. C. per minute is used drive off the sulphate. The remaining alumina is smelted by electrolysis for aluminum.
    Type: Grant
    Filed: April 19, 1996
    Date of Patent: February 24, 1998
    Assignee: Solv-Ex Corporation
    Inventors: John S. Rendall, Massoud Ahghar, Stephen J. Lane
  • Patent number: 5662880
    Abstract: A method of making activated alumina includes beginning with a leach liquor of potassium and aluminum sulphates that is subjected to a surface-cooled crystallizer with a heat-exchanger input temperature of 160.degree. F. and a surface-chilled temperature of 60.degree. F. to 80.degree. F. Crystals of aluminum sulphate are precipitated and recrystalized by evaporation in a vacuum and at an elevated temperature. Purified crystals of aluminum sulphate are then dried at 50.degree.-60.degree. C. The dried aluminum sulphate crystals are then dehydrated at 400.degree.-450.degree. C. after a rise rate of 10.degree.-20.degree. C. per minute to drive off most of the water. A roasting and recalcination step at 900.degree. C.-950.degree. C. after a rise rate of 10.degree.-20.degree. C. per minute is used drive off the sulphate. The remaining alumina is useful as a high-grade catalyst.
    Type: Grant
    Filed: April 19, 1996
    Date of Patent: September 2, 1997
    Assignee: Solv-Ex Corporation
    Inventors: John S. Rendall, Massoud Ahghar, Stephen J. Lane
  • Patent number: 5589023
    Abstract: An insulation material comprising the double salt of aluminum potassium sulphate and method of producing such. Aluminum sulphate materials and potassium sulphate materials are combined to form aluminum potassium sulphate which is then dehydrated to remove the water of hydration. Porous forms are made by mixing the hydrated aluminum potassium sulphate with a binder before dehydration. The resultant dehydrated sulphate expands greatly to provide an insulative material which is of lightweight and inorganic.
    Type: Grant
    Filed: April 26, 1995
    Date of Patent: December 31, 1996
    Assignee: Solv-Ex Corporation
    Inventors: John S. Rendall, Massoud Ahghar
  • Patent number: 5505823
    Abstract: A process for smelting aluminum from a mixture of a double salt potassium-aluminum sulfate 2KAl(SO.sub.4).sub.2 and aluminum sulfate Al.sub.2 (SO.sub.4).sub.3 with potassium sulfate K.sub.2 SO.sub.4 having a weight ratio of 2KAl(SO.sub.4).sub.2 to K.sub.2 SO.sub.4 in the range of 50/50 to 15/85. The mixture is heated to a eutectic temperature that makes it molten and electrolysis is used to precipitate out aluminum at the negative electrode and gases from SO.sub.4 ions at the positive electrode. A critical amount of a feed of 2KAl(SO.sub.4).sub.2 is added to replace that which was consumed in the electrolysis and to maintain the weight ratio which provides for the low eutectic melting temperature.
    Type: Grant
    Filed: September 2, 1994
    Date of Patent: April 9, 1996
    Assignee: Solv-Ex Corporation
    Inventor: John S. Rendall