Production of Hydrogen and their Use in Proton Exchange Membrane Fuel Cells

This work will show an overview of the hydrogen production from ethanol by steam reforming method, using distinct catalysts, resulting in low carbon monoxide content in H2 produced; a thermodynamic analysis of reforming employing entropy maximization, the ideal condition for ethanol, and other steam reforming reactions, the state of the art of steam reforming catalysts for H2 production with low CO content. Moreover, in the second part, there will be an overview of the use of hydrogen in a proton exchange membrane fuel cell (PEMFC), the fuel cell operational conditions, a thermodynamic analysis of PEMFC, the catalysts used in the electrodes of the fuel cell, consequences of the CO presence in the hydrogen fuel feed in PEMFC, and the operation conditions for maximum output power density

Recuperação de platina de eletrodos de células a combustível de membrana trocadora de prótons

Submitted by Ana Caroline Costa ([email protected]) on 2019-01-17T17:28:48Z No. of bitstreams: 2 Tese - André Mychell Barbieux Silva Sampaio - 2017.pdf: 3039584 bytes, checksum: cdc7e7e561ff4e4866a0b37cd1ba08ea (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)Approved for entry into archive by Luciana Ferreira ([email protected]) on 2019-01-18T09:54:23Z (GMT) No. of bitstreams: 2 Tese - André Mychell Barbieux Silva Sampaio - 2017.pdf: 3039584 bytes, checksum: cdc7e7e561ff4e4866a0b37cd1ba08ea (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)Made available in DSpace on 2019-01-18T09:54:23Z (GMT). No. of bitstreams: 2 Tese - André Mychell Barbieux Silva Sampaio - 2017.pdf: 3039584 bytes, checksum: cdc7e7e561ff4e4866a0b37cd1ba08ea (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-12-01The used platinum in proton exchange membrane fuel cell electrodes (PEMFC) was recovered by oxidation at high temperature using a muffle. Four materials with initial masses of 38.72 grams were prepared. The material was oxidized by acid and then the platinum concentration was determined by the atomic absorption method. Soon after, by reduction by sodium borohydride, the obtained metal was reduced to metal platinum on a carbon surface with high surface area. The material, after filtration and drying, was characterized by X-ray diffraction. The activity for electro-oxidation of hydrogen was evaluated by cyclic voltammetry in 0.5 mol.L -1 sulfuric acid and in acid solution containing 0,8 mol.L -1 of ethanol. For evaluation of the stability of the material formed chronoamperometry at several potentials for 600 s.A recuperação de platina usada em eletrodos de células a combustível de membrana trocadora de prótons (PEMFC) foi realizada através da oxidação do material em mufla. Foram preparadas 4 amostras. O material foi oxidado em água regia e, em seguida, determinada a concentração da platina por espectrofotometria de absorção atômica. Logo após, através de redução por borohidreto de sódio, o metal extraído foi reduzido a platina metálica em superfície de carbono com elevada área superficial. O material, após filtrado e seco, foi caracterizado através de difração de raios-X. A atividade para eletro-oxidação de hidrogênio foi avaliada através de voltametria cíclica em H 2 SO 4 0,5 mol.L -1 e em solução ácida contendo 0,8 mol.L -1 de etanol. Para avaliação da estabilidade do material foram feitas cronoamperometrias em vários potenciais durante 600 s