title: A weak-base fibrous anion exchanger effective for rapid phosphate removal from water.
abstract: This work investigated that weak-base anion exchange fibers named FVA-c and FVA-f were selectively and rapidly taken up phosphate from water. The chemical structure of both FVA-c and FVA-f was the same; i.e., poly(vinylamine) chains grafted onto polyethylene coated polypropylene fibers. Batch study using FVA-c clarified that this preferred phosphate to chloride, nitrate and sulfate in neutral pH region and an equilibrium capacity of FVA-c for phosphate was from 2.45 to 6.87 mmol/g. Column study using FVA-f made it clear that breakthrough capacities of FVA-f were not strongly affected by flow rates from 150 to 2000 h(-1) as well as phosphate feed concentration from 0.072 to 1.6mM. Under these conditions, breakthrough capacities were from 0.84 to 1.43 mmol/g indicating high kinetic performances. Trace concentration of phosphate was also removed from feeds containing 0.021 and 0.035 mM of phosphate at high feed flow rate of 2500 h(-1), breakthrough capacities were 0.676 and 0.741 mmol/g, respectively. The column study also clarified that chloride and sulfate did not strongly interfere with phosphate uptake even in their presence of equimolar and fivefold molar levels. Adsorbed phosphate on FVA-f was quantitatively eluted with 1M HCl acid and regenerated into hydrochloride form simultaneously for next phosphate adsorption operation. Therefore, FVA-f is able to use long time even under rigorous chemical treatment of multiple regeneration/reuse cycles without any noticeable deterioration.
authors.affiliation: Department of Applied Chemistry and Biochemistry, Kumamoto University, Kurokami 2-39-1, Kumamoto 860-8555, Japan. mdrabiul.awual@nims.go.jp
authors.forename: Md Rabiul
authors.initials: MR
authors.lastname: Awual
authors.forename: Akinori
authors.initials: A
authors.lastname: Jyo
authors.forename: Sherif A
authors.initials: SA
authors.lastname: El-Safty
authors.forename: Masao
authors.initials: M
authors.lastname: Tamada
authors.forename: Noriaki
authors.initials: N
authors.lastname: Seko
mesh_terms: D000327:Adsorption; D000837:Anion Exchange Resins / Q000737:chemistry; D007474:Ion Exchange; D010710:Phosphates / Q000302:isolation & purification*; D011126:Polypropylenes; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods
chemical_list: D000837:Anion Exchange Resins; D010710:Phosphates; D011126:Polypropylenes; D014874:Water Pollutants, Chemical