title: Flocculation of algal cells by amphoteric chitosan-based flocculant.
abstract: A kind of amphoteric chitosan-based flocculant (quaternized carboxymethyl chitosan, denoted as QCMC) has been prepared. QCMC presented significant improvement of water solubility in the whole pH range. The effects of pH, dosage, temperature and original turbidity of algal water on the flocculation performance were investigated. The optimal dosages of QCMC at pH 5, 9 and 12 with original turbidity of 20NTU at 20°C were 0.1, 0.6 and 2.0mg/L, respectively, which were much less than that of chitosan, PAM, Al2(SO4)3 and FeCl3. The floc properties during grow, breakage and regrow period were also evaluated at different pH values in terms of floc size, strength and density. It was demonstrated that QCMC produced larger, stronger and denser flocs than Al2(SO4)3. There is every indication that QCMC is more suitable for algal harvesting than other traditional coagulants or flocculants.
authors.affiliation: College of Environment, Hohai University, Nanjing 210098, PR China.
authors.forename: Changlong
authors.initials: C
authors.lastname: Dong
authors.affiliation: College of Environment, Hohai University, Nanjing 210098, PR China; Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, PR China. Electronic address: cwhhu5826@163.com.
authors.forename: Wei
authors.initials: W
authors.lastname: Chen
authors.affiliation: College of Environment, Hohai University, Nanjing 210098, PR China; Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, PR China.
authors.forename: Cheng
authors.initials: C
authors.lastname: Liu
mesh_terms: D002681:China; D048271:Chitosan / Q000031:analogs & derivatives* / Q000737:chemistry / Q000494:pharmacology; D005068:Eutrophication / Q000187:drug effects*; D005427:Flocculation / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D060106:Lakes / Q000382:microbiology*; D058086:Microalgae / Q000187:drug effects*; D008956:Models, Chemical; D009391:Nephelometry and Turbidimetry; D020005:Propanols; D000644:Quaternary Ammonium Compounds / Q000737:chemistry / Q000494:pharmacology*; D012995:Solubility; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D020005:Propanols; D000644:Quaternary Ammonium Compounds; C514968:carboxymethyl-chitosan; D048271:Chitosan; C496948:(3-chloro-2-hydroxypropyl)trimethylammonium chloride
keywords: Algae; Chitosan; Floc properties; Flocculation