title: Electrospray ionization time-of-flight mass spectrum analysis method of polyaluminum chloride flocculants.
abstract: Electrospray mass spectrometry has been reported as a novel technique for Al species identification, but to date, the working mechanism is not clear and no unanimous method exists for spectrum analysis of traditional Al salt flocculants, let alone for analysis of polyaluminum chloride (PAC) flocculants. Therefore, this paper introduces a novel theoretical calculation method to identify Al species from a mass spectrum, based on deducing changes in m/z (mass-to-charge ratio) and molecular formulas of oligomers in five typical PAC flocculants. The use of reference chemical species was specially proposed in the method to guarantee the uniqueness of the assigned species. The charge and mass reduction of the Al cluster was found to proceed by hydrolysis, gasification, and change of hydroxyl on the oxy bridge. The novel method was validated both qualitatively and quantitatively by comparing the results to those obtained with the (27)Al NMR spectrometry.
authors.affiliation: The Key Laboratory of Water and Sediment Sciences, Ministry of Education, School of Environment, Beijing Normal University , Beijing 100875, China.
authors.forename: Chenghong
authors.initials: C
authors.lastname: Feng
authors.forename: Zhe
authors.initials: Z
authors.lastname: Bi
authors.forename: Hongxiao
authors.initials: H
authors.lastname: Tang
mesh_terms: D000536:Aluminum Hydroxide / Q000032:analysis*; D005240:Feasibility Studies; D005427:Flocculation; D006868:Hydrolysis; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: C016213:aluminum oxychloride; D000536:Aluminum Hydroxide