title: Chemical filtration of Cr (VI) with electrospun chitosan nanofiber membranes.
abstract: Chitosan nanofibers (average diameter of 75nm) were electrospun on polyester (PET) scrim to form composite nanofiber membranes with controlled pore size. The membranes were then stacked as a membrane bed for chemical filtration of Cr (VI) of 1-5mg/L. The performance of the bed with respect to loading capacity at breakthrough, bed saturation and utilization efficiency were carefully investigated. The results showed that while these three parameters were dependent on pH, flow rate, flow distribution and packed pattern of the membrane, the latter two were less affected by feed Cr (VI) concentration and bed length. The maximum bed loading capacity for 1mg/L Cr (VI) filtration at breakthrough was found to be 16.5mg-chromium/g-chitosan, higher than the static adsorption capacity of 11.0mg-chromium/g-chitosan using nanofiber mats, indicating the membranes' better potential for dynamic adsorption. The minimum bed length required to avoid breakthrough was determined to be three layers of stacked membranes with nanofiber deposition density of 1g/m(2) by applying bed depth service time (BDST) model.
authors.affiliation: National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China; Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China; University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address: lileilyq@outlook.com.
authors.forename: Lei
authors.initials: L
authors.lastname: Li
authors.affiliation: National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China; Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China. Electronic address: yxli@ipe.ac.cn.
authors.forename: Yanxiang
authors.initials: Y
authors.lastname: Li
authors.affiliation: National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China; Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China. Electronic address: cfyang@ipe.ac.cn.
authors.forename: Chuanfang
authors.initials: C
authors.lastname: Yang
mesh_terms: D000327:Adsorption; D048271:Chitosan / Q000737:chemistry*; D002857:Chromium / Q000737:chemistry / Q000302:isolation & purification*; D005374:Filtration / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D008567:Membranes, Artificial; D057139:Nanofibers / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000302:isolation & purification*; D018508:Water Purification
chemical_list: D008567:Membranes, Artificial; D014874:Water Pollutants, Chemical; D002857:Chromium; D048271:Chitosan
keywords: Breakthrough curves; Chemical filtration; Chromium (VI) adsorption; Electrospun chitosan nanofiber membrane; Model fitting