title: Natural clinoptilolite composite membranes on tubular stainless steel supports for water softening.
abstract: Disk membranes generated from high-purity natural clinoptilolite mineral rock have shown promising water desalination and de-oiling performance. In order to scale up production of these types of membranes for industrial wastewater treatment applications, a coating strategy was devised. A composite mixture of natural clinoptilolite from St. Cloud (Winston, NM, USA) and aluminum phosphate was deposited on the inner surface of porous stainless steel tubes by the slip casting technique. The commercial porous stainless steel tubes were pre-coated with a TiO2 layer of about 10 μm. Phase composition and morphology of the coating materials were investigated using X-ray diffraction and scanning electron microscopy. Water softening performance of the fabricated membranes was evaluated using Edmonton (Alberta, Canada) municipal tap water as feed source. Preliminary experimental results show a high water flux of 7.7 kg/(m(2) h) and 75% reduction of hardness and conductivity in a once-through membrane process at 95 °C and feed pressure of 780 kPa. These results show that natural zeolite coated, stainless steel tubular membranes have high potential for large-scale purification of oil sands steam-assisted gravity drainage water at high temperature and pressure requirements.
authors.affiliation: Department of Chemical and Materials Engineering, University of Alberta, Edmonton, AB, Canada T6G 2V4 E-mail: steve.kuznicki@ualberta.ca.
authors.forename: Solmaz
authors.initials: S
authors.lastname: Adamaref
authors.affiliation: Department of Chemical and Materials Engineering, University of Alberta, Edmonton, AB, Canada T6G 2V4 E-mail: steve.kuznicki@ualberta.ca.
authors.forename: Weizhu
authors.initials: W
authors.lastname: An
authors.affiliation: Department of Chemical and Materials Engineering, University of Alberta, Edmonton, AB, Canada T6G 2V4 E-mail: steve.kuznicki@ualberta.ca.
authors.forename: Maria Ophelia
authors.initials: MO
authors.lastname: Jarligo
authors.affiliation: Department of Chemical and Materials Engineering, University of Alberta, Edmonton, AB, Canada T6G 2V4 E-mail: steve.kuznicki@ualberta.ca.
authors.forename: Tetyana
authors.initials: T
authors.lastname: Kuznicki
authors.affiliation: Department of Chemical and Materials Engineering, University of Alberta, Edmonton, AB, Canada T6G 2V4 E-mail: steve.kuznicki@ualberta.ca.
authors.forename: Steven M
authors.initials: SM
authors.lastname: Kuznicki
mesh_terms: D000416:Alberta; D060766:Drinking Water; D007220:Industrial Waste; D008567:Membranes, Artificial; D008855:Microscopy, Electron, Scanning; D061329:Oil and Gas Fields; D013193:Stainless Steel; D014865:Waste Disposal, Fluid / Q000379:methods; D018508:Water Purification / Q000295:instrumentation* / Q000379:methods; D014880:Water Softening / Q000295:instrumentation* / Q000379:methods; D014961:X-Ray Diffraction; D017641:Zeolites
chemical_list: D060766:Drinking Water; D007220:Industrial Waste; D008567:Membranes, Artificial; C083175:clinoptilolite; D013193:Stainless Steel; D017641:Zeolites