title: Reactive red 120 retention through ultrafiltration enhanced by synthetic and natural polyelectrolytes.
abstract: Two cationic chelating polymers, namely synthetic polyethylenimine (PEI), and biopolymer chitosan were employed in the present study to bring about the retention of anionic reactive red 120 (RR 120) from its aqueous solutions by way of polymer enhanced ultrafiltration (PEUF). The effects of process parameters, namely, cross-flow rate, transmembrane pressure, time, polyelectrolyte loading, and ionic strength on dye retention and permeation flux were examined. PEI enhanced ultrafiltration achieved dye retentions as high as 99.9%, and significant permeation fluxes around 148 L/m(2)h. However, in case of chitosan, relatively low retention (88%), and flux (120 L/m(2)h) levels were observed. A careful comparison of the changes induced in the UV-vis spectra of RR 120 by PEI and chitosan indicated a predominant electrostatic interaction between PEI and RR 120, as opposed to the relatively weak and sterically as well as chemically hindered interaction between chitosan and the dye ion. The respective binding constants of PEI-RR 120, and PEI-chitosan complexes, in addition to the relatively more pronounced permeation flux decline witnessed in the presence of chitosan, clearly advocated the use of PEI, rather than chitosan, as the most appropriate complexing agent in the present context.
authors.affiliation: Department of Chemical Engineering, National Institute of Technology Durgapur, West Bengal 713209, India.
authors.forename: Jhilly
authors.initials: J
authors.lastname: Dasgupta
authors.affiliation: Department of Chemical Engineering, National Institute of Technology Durgapur, West Bengal 713209, India. Electronic address: umuniqueme1@gmail.com.
authors.forename: Jaya
authors.initials: J
authors.lastname: Sikder
authors.affiliation: Department of Chemical Engineering, National Institute of Technology Durgapur, West Bengal 713209, India.
authors.forename: Tamal
authors.initials: T
authors.lastname: Mandal
authors.affiliation: Department of Chemistry, National Institute of Technology Durgapur, West Bengal 713209, India.
authors.forename: Utpal
authors.initials: U
authors.lastname: Adhikari
mesh_terms: D004573:Electrolytes / Q000737:chemistry*; D014227:Triazines / Q000302:isolation & purification*; D014462:Ultrafiltration
chemical_list: D004573:Electrolytes; D014227:Triazines; C042516:reactive red 120 dye
keywords: Chitosan; Dye retention; Polyethylenimine; Polymer enhanced ultrafiltration; Reactive red 120