Patents by Inventor Arturo J. Hernandez-Maldonado

Arturo J. Hernandez-Maldonado 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: 20240042415
    Abstract: A bi-metallic coordination polymer comprising a transition metal and an alkaline earth metal is provided. In one aspect, the present disclosure provides a coordination polymer comprising a plurality of two-dimensional sheets, wherein the two-dimensional sheets arranged in parallel and comprising a plurality of transition metal cations coordinated by carboxylate-bearing ligands; and a plurality of pillars, wherein each pillar connects two adjacent two-dimensional sheets, and wherein each pillar is comprised of an alkaline earth metal coordinated to at least one ?-diketonate moiety.
    Type: Application
    Filed: July 28, 2023
    Publication date: February 8, 2024
    Inventors: Arturo J. Hernandez-Maldonado, Alberto Tous-Granados
  • Patent number: 10369544
    Abstract: The invention employs tetrapropylammonium (TPA+) and tetrabutylammonium (TBA+) as structure directing agents (SDAs), respectively for the preparation of the flexible titanium silicate UPRM-5. Both UPRM-5 variants are detemplated and modified to include extraframework Sr2+ and produce materials for carbon dioxide adsorption.
    Type: Grant
    Filed: May 13, 2013
    Date of Patent: August 6, 2019
    Assignee: University of Puerto Rico
    Inventors: Arturo J. Hernandez-Maldonado, Marietta E. Marcano-Gonzalez, Jose N. Primera-Pedrozo
  • Patent number: 10272414
    Abstract: Na+-SAPO-34 sorbents were ion-exchanged with several individual metal cations for CO2 absorption at different temperatures (273-348 K) and pressures (<1 atm). In general, the overall adsorption performance of the exchanged materials increased as follows: Ce3+<Ti3+<Mg2+<Ca2+<Ag+<Na+<Sr2+. The strontium exchanged materials excelled at low-pressure ranges, exhibiting very sharp isotherms slopes at all temperatures. The Sr2+ species were responsible for the surface strong interaction and the cations were occupying exposed sites (SII?) in the materials Chabazite cages. All the sorbent materials exhibited higher affinity for CO2 over the other gases tested (i.e., CH4, H2, N2 and O2) due to strong ion-quadrupole interactions. Sr2+-SAPO-34 sorbents are by far the best option for CO2 removal from CH4 mixtures, especially at low concentrations.
    Type: Grant
    Filed: August 24, 2016
    Date of Patent: April 30, 2019
    Assignee: University of Puerto Rico
    Inventors: Arturo J Hernandez-Maldonado, Milton E Rivera-Ramos, Ana G Arevalo-Hidalgo
  • Patent number: 10052610
    Abstract: Na+-SAPO-34 sorbents were ion-exchanged with several individual metal cations for CO2 absorption at different temperatures (273-348 K) and pressures (<1 atm). In general, the overall adsorption performance of the exchanged materials increased as follows: Ce3+<Ti3+<Mg2+<Ca2+<Ag+<Na+<Sr2+. The strontium exchanged materials excelled at low-pressure ranges, exhibiting very sharp isotherms slopes at all temperatures. The Sr2+ species were responsible for the surface strong interaction and the cations were occupying exposed sites (SII?) in the materials Chabazite cages. All the sorbent materials exhibited higher affinity for CO2 over the other gases tested (i.e., CH4, H2, N2 and O2) due to strong ion-quadrupole interactions. Sr2+-SAPO-34 sorbents are by far the best option for CO2 removal from CH4 mixtures, especially at low concentrations.
    Type: Grant
    Filed: December 15, 2008
    Date of Patent: August 21, 2018
    Assignee: University of Puerto Rico
    Inventors: Arturo J Hernandez-Maldonado, Milton E Rivera-Ramos, Ana G Arevalo-Hidalgo
  • Patent number: 9623364
    Abstract: Na+-SAPO-34 sorbents were ion-exchanged with several individual metal cations for CO2 absorption at different temperatures (273-348 K) and pressures (<1 atm). In general, the overall adsorption performance of the exchanged materials increased as follows: Ce3+<Ti3+<Mg2+<Ca2+<Ag+<Na+<Sr2+. The strontium exchanged materials excelled at low-pressure ranges, exhibiting very sharp isotherms slopes at all temperatures. The Sr2+ species were responsible for the surface strong interaction and the cations were occupying exposed sites (SII?) in the materials Chabazite cages. All the sorbent materials exhibited higher affinity for CO2 over the other gases tested (i.e., CH4, H2, N2 and O2) due to strong ion-quadrupole interactions. Sr2+-SAPO-34 sorbents are by far the best option for CO2 removal from CH4 mixtures, especially at low concentrations.
    Type: Grant
    Filed: August 24, 2016
    Date of Patent: April 18, 2017
    Assignee: University of Puerto Rico
    Inventors: Arturo J Hernandez-Maldonado, Milton E Rivera-Ramos, Ana G Arevalo-Hidalgo
  • Patent number: 7094333
    Abstract: A method for removing thiophene and thiophene compounds from liquid fuel includes contacting the liquid fuel with an adsorbent which preferentially adsorbs the thiophene and thiophene compounds. The adsorption takes place at a selected temperature and pressure, thereby producing a non-adsorbed component and a thiophene/thiophene compound-rich adsorbed component. The adsorbent includes either a metal or a metal cation that is adapted to form ?-complexation bonds with the thiophene and/or thiophene compounds, and the preferential adsorption occurs by ?-complexation. A further method includes selective removal of aromatic compounds from a mixture of aromatic and aliphatic compounds.
    Type: Grant
    Filed: December 3, 2003
    Date of Patent: August 22, 2006
    Assignee: The Regents of the University of Michigan
    Inventors: Ralph T. Yang, Arturo J. Hernandez-Maldonado, Frances H. Yang, Akira Takahashi
  • Patent number: 7053256
    Abstract: A method for removing thiophene and thiophene compounds from liquid fuel includes contacting the liquid fuel with an adsorbent which preferentially adsorbs the thiophene and thiophene compounds. The adsorption takes place at a selected temperature and pressure, thereby producing a non-adsorbed component and a thiophene/thiophene compound-rich adsorbed component. The adsorbent includes either a metal or a metal cation that is adapted to form ?-complexation bonds with the thiophene and/or thiophene compounds, and the preferential adsorption occurs by ?-complexation. A further method includes selective removal of aromatic compounds from a mixture of aromatic and aliphatic compounds.
    Type: Grant
    Filed: July 3, 2003
    Date of Patent: May 30, 2006
    Assignee: The Regents of the University of Michigan
    Inventors: Ralph T. Yang, Frances H. Yang, Akira Takahashi, Arturo J. Hernandez-Maldonado
  • Patent number: 7029574
    Abstract: A method for removing thiophene and thiophene compounds from liquid fuel includes contacting the liquid fuel with an adsorbent which preferentially adsorbs the thiophene and thiophene compounds. The adsorption takes place at a selected temperature and pressure, thereby producing a non-adsorbed component and a thiophene/thiophene compound-rich adsorbed component. The adsorbent includes either a metal or a metal ion that is adapted to form ?-complexation bonds with the thiophene and/or thiophene compounds, and the preferential adsorption occurs by ?-complexation. A further method includes selective removal of aromatic compounds from a mixture of aromatic and aliphatic compounds.
    Type: Grant
    Filed: March 21, 2003
    Date of Patent: April 18, 2006
    Assignee: The Regents of the University of Michigan
    Inventors: Ralph T. Yang, Frances H. Yang, Akira Takahashi, Arturo J. Hernandez-Maldonado
  • Publication number: 20040200758
    Abstract: A method for removing thiophene and thiophene compounds from liquid fuel includes contacting the liquid fuel with an adsorbent which preferentially adsorbs the thiophene and thiophene compounds. The adsorption takes place at a selected temperature and pressure, thereby producing a non-adsorbed component and a thiophene/thiophene compound-rich adsorbed component. The adsorbent includes either a metal or a metal cation that is adapted to form &pgr;-complexation bonds with the thiophene and/or thiophene compounds, and the preferential adsorption occurs by &pgr;-complexation. A further method includes selective removal of aromatic compounds from a mixture of aromatic and aliphatic compounds.
    Type: Application
    Filed: December 3, 2003
    Publication date: October 14, 2004
    Inventors: Ralph T. Yang, Arturo J. Hernandez-Maldonado, Frances H. Yang, Akira Takahashi
  • Publication number: 20040040891
    Abstract: CuY and AgY zeolites as selective sorbents for desulfurization of liquid fuels. Thiophene and benzene were used as the model system, and vapor phase isotherms were measured. Compared with NaY, CuY and AgY adsorbed significantly larger amounts of both thiophene and benzene at low pressures. It is hypothesized that this is due to &pgr;-complexation with Cu+ and Ag+. On a per-cation basis, more thiophene was adsorbed by Cu+ than by Ag+, e.g., 0.92 molecule/Cu+ versus 0.42 molecule/Ag+ at 2×10−5 atm and 120° C. Molecular orbital calculations confirmed the relative strengths of &pgr;-complexation: thiophene>benzene and Cu+>Ag+. The experimental heats of adsorption for &pgr;-complexation are in qualitative agreement with theoretical predictions. The invention further comprises a process and sorbents for removal of aromatics from hydrocarbons.
    Type: Application
    Filed: March 21, 2003
    Publication date: March 4, 2004
    Inventors: Ralph T. Yang, Frances H. Yang, Akira Takahashi, Arturo J. Hernandez-Maldonado
  • Publication number: 20040044262
    Abstract: CuY and AgY zeolites as selective sorbents for desulfurization of liquid fuels. Thiophene and benzene were used as the model system, and vapor phase isotherms were measured. Compared with NaY, CuY and AgY adsorbed significantly larger amounts of both thiophene and benzene at low pressures. It is hypothesized that this is due to &pgr;-complexation with Cu+ and Ag+. On a per-cation basis, more thiophene was adsorbed by Cu+ than by Ag+, e.g., 0.92 molecule/Cu+ versus 0.42 molecule/Ag+ at 2×10−5 atm and 120° C. Molecular orbital calculations confirmed the relative strengths of &pgr;-complexation: thiophene>benzene and Cu+>Ag+. The experimental heats of adsorption for &pgr;-complexation are in qualitative agreement with theoretical predictions. The invention further comprises a process and sorbents for removal of aromatics from hydrocarbons.
    Type: Application
    Filed: July 3, 2003
    Publication date: March 4, 2004
    Inventors: Ralph T. Yang, Frances H. Yang, Akira Takahashi, Arturo J. Hernandez-Maldonado
  • Publication number: 20030163013
    Abstract: CuY and AgY zeolites as selective sorbents for desulfurization of liquid fuels. Thiophene and benzene were used as the model system, and vapor phase isotherms were measured. Compared with NaY, CuY and AgY adsorbed significantly larger amounts of both thiophene and benzene at low pressures. It is hypothesized that this is due to &pgr;-complexation with Cu+ and Ag+. On a per-cation basis, more thiophene was adsorbed by Cu+ than by Ag+, eg. 0.92 molecule/Cu+ versus 0.42 molecule/Ag+ at 2×10−5 atm and 120° C. Molecular orbital calculations confirmed the relative strengths of &pgr;-complexation: thiophene>benzene and Cu+>Ag+. The experimental heats of adsorption for &pgr;-complexation are in qualitative agreement with theoretical predictions. The invention further comprises a process and sorbents for removal of aromatics from hydrocarbons.
    Type: Application
    Filed: September 4, 2002
    Publication date: August 28, 2003
    Inventors: Ralph T. Yang, Frances H. Yang, Akira Takahashi, Arturo J. Hernandez-Maldonado