title: The spectrophotometric determination of trace molybdenum (VI) after collection and elution as molybdate ion on protonated chitin.
abstract: Collection and elution method for inorganic anion on protonated chitin has been applied to the spectrophotometric determination of molybdenum (VI). The molybdenum (VI) is collected as molybdate ion on a column of chitin in weak acidic medium which is easily eluted with a small volume of 0.1 M ammonia buffer solution (pH 10). The molybdenum (VI) in the eluent is determined by bromopyrogallol red-Zephiramine method spectrophotometrically. Beer's law is obeyed over the concentration range of 0.1-0.8 mug of molybdenum (VI) in 1 ml of eluent at 634 nm. The apparent molar absorptivity is 6x10(4) dm(3) mol(-1) cm(-1). The tolerance limits for WO(4)(2-), VO(3)(-), CrO(4)(2-) and Fe (III) is low, that is, 1-100 times that of molybdenum (VI), but some metal ions and common inorganic anions do not interfere in concentration range of 1000-5000 times that of molybdenum (VI). The present method can be applied to the determination of molybdenum (VI) in natural water samples.
authors.affiliation: Department of Applied and Environmental Chemistry, Kitami Institute of Technology, 165 Koen-cho, Kitami-shi 090, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Hoshi
authors.forename: K
authors.initials: K
authors.lastname: Konuma
authors.forename: K
authors.initials: K
authors.lastname: Sugawara
authors.forename: M
authors.initials: M
authors.lastname: Uto
authors.forename: K
authors.initials: K
authors.lastname: Akatsuka