@article{TrautmannHoldt2015,
  author    = {Trautmann, Michael and Holdt, Hans-J{\"u}rgen},
  title     = {Separation of platinum and ruthenium by a sulphoxide modified polystyrene resin in laboratory column systems},
  series = {Separation and purification technology},
  volume    = {149},
  journal   = {Separation and purification technology},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1383-5866},
  doi       = {10.1016/j.seppur.2015.05.013},
  pages     = {279 -- 287},
  year      = {2015},
  abstract  = {The present study deals with the adsorption performance of fixed bed columns using powdered sulphoxide modified poly(styrene-co-divinylbenzene) (d(10) < 13 mu m, d(50) < 30 mu m, d(90) < 50 mu m) for the separation of platinum and ruthenium from hydrochloric acidic solutions containing both metals (c(Pt) = 20 mg/L, c(Ru) = 10 mg/L). The influence of hydrochloric acid concentration, temperature, flow rate, flow direction, redox potential and bed height on the breakthrough characteristics was examined. Platinum was separately adsorbed mainly induced by hydrochloric acid concentration and redox potential keeping platinum as Pt-IV and ruthenium as Ru-III. Ruthenium was separately adsorbed to 90\% essentially induced by hydrochloric acid concentration, temperature and redox potential keeping platinum as Pt-IV and ruthenium predominantly as Ru-IV. Experimental data at optimised separation conditions were fitted to different kinetic models (Thomas, Yoon-Nelson, Bohart-Adams, Wolborska) to characterise the fixed bed column behaviour. Adsorption of both metals was well described by Thomas and Yoon-Nelson model with correlation coefficients R-2 >= 0.95 whereas Bohart-Adams and Wolborska model were less suitable. (C) 2015 Elsevier B.V. All rights reserved.},
  language  = {en}
}
@article{TrautmannLubahnHoldt2014,
  author    = {Trautmann, Michael and Lubahn, Susanne and Holdt, Hans-J{\"u}rgen},
  title     = {Preparation, characterisation and properties of sulphoxide modified polystyrene resins for solid-phase extraction of Pt-IV, Ru-III and Ru-IV from hydrochloric acid},
  series = {Reactive \& functional polymers},
  volume    = {83},
  journal   = {Reactive \& functional polymers},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1381-5148},
  doi       = {10.1016/j.reactfunctpolym.2014.07.001},
  pages     = {84 -- 97},
  year      = {2014},
  abstract  = {New sulphoxide modified resins were synthesized using poly(styrene-co-divinylbenzene) (PS-DVB) as matrix. Infrared spectroscopy and elemental analysis were used for characterisation. Solid-phase extraction of Pt-IV, Ru-III and Ru-IV from acidic chloride solutions was performed via batch experiments. Influence of spacer length between sulphoxide and matrix (ethylene, hexamethylene), substitution of sulphoxide (R-1: ethyl, hexyl, phenyl) and bead size of PS-DVB (spherical beads: d(50) < 155 mu m, d(50) < 80 mu m; powder: d(50) < 30 mu m) on adsorption was investigated subjected to acidity. Experimental results showed that ethyl substituted sulphoxide immobilised onto ground PS-DVB and hexamethylene spacer exhibited best adsorption properties. Different kinetic models and isotherms were fitted to the experimental data to identify extraction mechanism. Pt-IV was quantitative sorbed at [HCl] <= 0.1 mol/L whereas Ru-III and Ru-IV sorption ranged between 90\% and 95\% at [HCl] 5 mol/L. Desorption was reached using a solution of 0.5 M thiourea (Tu) in 0.1 M HCl at 90 degrees C. Separation of Pt-IV and Rum occurred at [HCl] <= 0.1 mol/L whereas Pt-IV was extracted and Ru-III remained in solution. A further separation was achieved by extracting Pt-IV and Ru-IV at 5 M HCl followed by sequential elution of Pt-IV with concentrated HCl and Ru-IV with 0.5 M Tu in 0.1 M HCl at 90 degrees C. 2014 Elsevier B.V. All rights reserved.},
  language  = {en}
}
@article{HahnHoldt2012,
  author    = {Hahn, Simone and Holdt, Hans-J{\"u}rgen},
  title     = {Extraction of hexachloroplatinate from hydrochloric acid solutions with phosphorylated hexane-1,6-diyl polymers},
  series = {Reactive \& functional polymers},
  volume    = {72},
  journal   = {Reactive \& functional polymers},
  number    = {11},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1381-5148},
  doi       = {10.1016/j.reactfunctpolym.2012.08.004},
  pages     = {878 -- 888},
  year      = {2012},
  abstract  = {A series of diols (diethylene glycol, triethylene glycol, butane-1,4-diol and hexane-1,6-diol) were immobilized onto Merrifield resin and subsequently phosphorylated with dialkyl chlorophosphate (alkyl = Me, Et, Bu). The resins bearing hexane-1,6-diyl groups exhibited very good extraction abilities in regard to precious metal chloro complexes like platinum(IV), palladium(II) and rhodium(III). In batch experiments, more than 98\% of Pt(IV) is extracted even when the metal and the hydrochloric acid concentration is enhanced significantly. Elution can be achieved with a solution of 0.5 mol L-1 thiourea in 0.1 mol L-1 hydrochloric acid. In the presence of other noble metals, platinum(IV) is preferentially bound. The extraction yield decreases in slightly acidic solution in the following order: Pt(IV)approximate to Pd(II)>Rh(III) and changes with increasing hydrochloric acid concentration to Pt(IV)>Pd(II)>> Rh(III). At different ratios of metal and acid, the temperature has nearly no influence on the platinum extraction. On slightly acidic media, the extraction of rhodium decreases by 30\% when the temperature is increased from 10 degrees C to 40 degrees C. When the acid and metal concentration is enhanced, the palladium extraction decreases by 7-9\%, depending on the resin.},
  language  = {en}
}