Affordable Access

Winther-Jensen, Bjørn

  • Chemistry
  • Design


Bjørn Winther-Jensen - DTU Orbit (17/05/14) Bjørn Winther-Jensen - DTU Orbit (17/05/14) Bjørn Winther-Jensen Risø National Laboratory for Sustainable Energy 09/04/08 to 03/09/13 Department of Chemical and Biochemical Engineering 04/07/03 to 03/09/13 423, 014 [email protected] Phone: 45252953 Job title: PhD student Publications: Surface modification of chromatography adsorbents by low temperature low pressure plasma In this study we show how low temperature glow discharge plasma can be used to prepare bi-layered chromatography adsorbents with non-adsorptive exteriors. The commercial strong anion exchange expanded bed chromatography matrix, Q HyperZ, was treated with plasmas in one of two general ways. Using a purpose-designed rotating reactor, plasmas were employed to either: (i) remove anion exchange ligands at or close to the exterior surface of Q HyperZ, and replace them with polar oxygen containing functions (‘plasma etching and oxidation’); or (ii) bury the same surface exposed ligands beneath thin polymer coatings (‘plasma polymerization coating’) using appropriate monomers (vinyl acetate, vinyl pyrrolidone, safrole) and argon as the carrier gas. X-ray photoelectron spectroscopy analysis (first 10 nm depth) of Q HyperZ before and after the various plasma treatments confirmed that substantial changes to the elemental composition of Q HyperZ's exterior had been inflicted in all cases. The atomic percent changes in carbon, nitrogen, oxygen, yttrium and zirconium observed after being exposed to air plasma etching were entirely consistent with: the removal of pendant Q (trimethylammonium) functions; increased exposure of the underlying yttrium-stabilised zirconia shell; and introduction of hydroxyl and carbonyl functions. Following plasma polymerization treatments (with all three monomers tested), the increased atomic percent levels of carbon and parallel drops in nitrogen, yttrium and zirconium provided clear evidence that thin polymer coats had b

There are no comments yet on this publication. Be the first to share your thoughts.