A flow injection procedure using Layered Double Hydroxide for on line pre-concentration of fluoride

TALANTA

卷:178

Article

Rocha, Diego P.¹  Terra, Gabriel C.¹  Nery, Thais S.¹  Tronto, Jairo²  Pinto, Frederico G.²  Silva, Sidnei G.¹  Coelho, Nivia M. M.¹ 

[1] Univ Fed Uberlandia, Inst Chem, Ave Joao Naves Avila,2121, BR-38400902 Uberlandia, MG, Brazil

[2] Univ Fed Vicosa, Inst Exact & Technol Sci, Campus Rio Paranaiba,Rodovia MG-230 Km 8, BR-38810000 Rio Paranaiba, MG, Brazil

关键词: Flow analysis;    Multicommutation;    SPADNS;    Fluoride;    Layered double hydroxides;   

DOI  :  10.1016/j.talanta.2017.09.015

来源: Elsevier

【 摘 要 】

This work showed a flow system designed with solenoid valves for preconcentration of fluoride using SPADNS method in water samples. The analyte was preconcentrated in a mini-column coated with Layered Double Hydroxides (LDH) used as adsorbent. Then, the fluoride ions were eluted with 0.5 mol L-1 sodium hydroxide and determined by spectrophotometry. The variables that affect the system such adsorbent mass, type of eluent, solutions flow rate, reagent concentration and pH effect were critically evaluated. Under optimized conditions, the detection limit, coefficient of variation, linear range and preconcentration factor were estimated at 15 mu g L-1 (99.7% confidence level), 0.8% (500 mu g L-1, n = 10), 50-500 mu g L-1 and 10, respectively. The accuracy of the method was evaluated by analysis of ALPHA APS 1076 (Simulated Rain Water) certified material, the values were not significantly different at a 95% level of confidence. The method was applied for fluoride determination in water samples and the levels found were below the maximum values established by Brazilian environmental and health legislations.

【 授权许可】

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