title: Comparing graphene, carbon nanotubes, and superfine powdered activated carbon as adsorptive coating materials for microfiltration membranes.
abstract: Multi-walled carbon nanotubes (MWCNTs), nano-graphene platelets (NGPs), and superfine powdered activated carbon (S-PAC) were comparatively evaluated for their applicability as adsorptive coatings on microfiltration membranes. The objective was to determine which materials were capable of contaminant removal while causing minimal flux reduction. Methylene blue and atrazine were the model contaminants. When applied as membrane coatings, MWCNTs had minimal retention capabilities for the model contaminants, and S-PAC had the fastest removal. The membrane coating approach was also compared with a stirred vessel configuration, in which the adsorbent was added to a stirred flask preceding the membrane cell. Direct application of the adsorbent to the membrane constituted a greater initial reduction in permeate concentrations of the model contaminants than with the stirred flask setup. All adsorbents except S-PAC showed flux reductions less than 5% after application as thin-layer membrane coatings, and flux recovery after membrane backwashing was greater than 90% for all materials and masses tested.
authors.affiliation: Department of Environmental Engineering and Earth Sciences, Clemson University, 342 Computer Court, Anderson, SC 29625 United States.
authors.forename: Jaclyn R
authors.initials: JR
authors.lastname: Ellerie
authors.forename: Onur G
authors.initials: OG
authors.lastname: Apul
authors.forename: Tanju
authors.initials: T
authors.lastname: Karanfil
authors.forename: David A
authors.initials: DA
authors.lastname: Ladner
mesh_terms: D000327:Adsorption; D001280:Atrazine / Q000737:chemistry; D002244:Carbon / Q000737:chemistry*; D008567:Membranes, Artificial; D008751:Methylene Blue / Q000737:chemistry; D010316:Particle Size; D011208:Powders; D014462:Ultrafiltration; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D018508:Water Purification / Q000295:instrumentation / Q000379:methods*
chemical_list: D008567:Membranes, Artificial; D011208:Powders; D014874:Water Pollutants, Chemical; D002244:Carbon; D001280:Atrazine; D008751:Methylene Blue
keywords: Adsorption; Aggregation; Nanomaterials; Trace contaminants