title: Ammonium across a Selective Polymer Inclusion Membrane: Characterization, Transport, and Selectivity.
abstract: The recovery of ammonium from urine requires distinguishing and excluding sodium and potassium. A polymer inclusion membrane selective for ammonium is developed using an ionophore based on pyrazole substituted benzene. The interactions of the components are studied, as well as their effect on transport and selectivity. Spectroscopic and thermogravimetric measurements show no extensive physical interactions of the components, and that the plasticizer reduces the intermolecular forces (rigidity) of the membrane. The ionophore turns the membrane more rigid, although it increases its swelling degree and therefore the affinity of cations. A ratio of plasticizer (DEHP) and polymer (PVC) of 1:3 in mass gives the highest ammonium flux. Tested contents of ionophore (2 and 5 wt%) show that the higher the content of the ionophore, the fastest the flux is (7.5 × 10(-3) mmol cm(-2) h(-1) ). Selectivity of NH4 (+) over Na(+) and over K(+) is reduced from 13.07 to 9.33 and from 14.15 to 9.57 correspondingly.
authors.affiliation: Department of Polymer Chemistry, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747, AG, Groningen, The Netherlands.|Wetsus, European Centre of Excellence for Sustainable Water Technology, P. O. Box 1113, 8911, MA, Leeuwarden, The Netherlands.
authors.forename: Anna
authors.initials: A
authors.lastname: Casadellà
authors.affiliation: Wetsus, European Centre of Excellence for Sustainable Water Technology, P. O. Box 1113, 8911, MA, Leeuwarden, The Netherlands.
authors.forename: Olivier
authors.initials: O
authors.lastname: Schaetzle
authors.affiliation: Department of Polymer Chemistry, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747, AG, Groningen, The Netherlands.
authors.forename: Katja
authors.initials: K
authors.lastname: Loos
mesh_terms: D064751:Ammonium Compounds / Q000737:chemistry / Q000378:metabolism*; D001554:Benzene / Q000737:chemistry; D002412:Cations; D017136:Ion Transport; D008567:Membranes, Artificial; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry / Q000378:metabolism*; D011720:Pyrazoles / Q000737:chemistry
chemical_list: D064751:Ammonium Compounds; D002412:Cations; D008567:Membranes, Artificial; D011108:Polymers; D011720:Pyrazoles; D001554:Benzene
keywords: ammonium; ion selectivity; ion transport; ionophores; polymer inclusion membranes