Direct simultaneous determination for ultratrace As, Se and Sb in river water with graphite-furnace atomic absorpion spectrometry by TiO2-slurry sampling.

A simple analytical method was established for the simultaneous multielement determination of As, Se and Sb in river water with GF-AAS using TiO2-slurry sampling. Titanium dioxide (TiO2, <0.5 microm) was applied as a sorbent to separate and concentrate these elements in a sample solution (100-300 ml); after filtration, a slurry was prepared with the solid phase and 5.0 ml of ultrapure water. In order to apply to river-water samples, the effect of TiO2 in atomization, the effect of organic species of their metal and the interference of foreign ions were investigated. The proposed method was applied to JSAC 0302 and river water.

Inorganic speciation of As(III, V), Se(IV, VI) and Sb(III, V) in natural water with GF-AAS using solid phase extraction technology.

The paper presents a procedure for the multi-element inorganic speciation of As(III, V), Se(IV, VI) and Sb(III, V) in natural water with GF-AAS using solid phase extraction technology. Total As(III, V), Se(IV, VI) and Sb(III, V) were determined according to the following procedure: titanium dioxide (TiO(2)) was used to adsorb inorganic species of As, Se and Sb in sample solution; after filtration, the solid phase was prepared to be slurry for determination. For As(III), Se(IV) and Sb(III), their inorganic species were coprecipitated with Pb-PDC, dissolved in dilute nitric acid, and then determined. The concentrations of As(V), Se(VI) and Sb(V) can be calculated by the difference of the concentrations obtained by the above determinations. For the determination of As(III), Se(IV) and Sb(III), palladium was chosen as a modifier and pyrolysis temperature was 800 degrees C. Optimum conditions for the coprecipitation were listed for 100ml of sample solution: pH 3.0, 15min of stirring time, 40.0mugl(-1) Pb(NO(3))(2) and 150.0mugl(-1) APDC. The proposed method was applied to the determination of trace amounts of As(III, V), Se(IV, VI) and Sb(III, V) in river water and seawater.

Study on simultaneous speciation of arsenic and antimony by HPLC-ICP-MS.

A method was developed for the simultaneous speciation of arsenic and antimony with HPLC-ICP-MS using C30 reversed phase column. Eight kinds of arsenic compounds (As(III), As(V), monomethylarsonic acid (MMAA), dimethylarsinic acid (DMAA), arsenobetaine (AB), arsenocholine (AsC), trimethylarsine oxide (TMAO) and tetramethylarsonium (TeMA)), Sb(III) and Sb(V) were simultaneously separated by the special mobile phase containing ammonium tartrate. Especially for the species of organic As, a C30 column was better than a C18 column in the effect of separation. Limits of detection (LOD) for these elements were 0.2 ng ml(-1) for the species of each As, and 0.5 ng ml(-1) for the species of each Sb, when a 10 microl of sample was injected, respectively. The proposed method was applied to a hot spring water and a fish sample.

Simultaneous multi-element analysis of total As, Se and Sb on titanium dioxide by slurry sampling-graphite furnace atomic absorption spectrometry.

A simple and rapid method for simultaneous determination of As, Se and Sb was studied by graphite furnace atomic absorption spectrometry (GFAAS). Titanium dioxide adsorbing As, Se and Sb was separated from sample solution (100ml) with a membrane filtration (0.45mum), and then prepared to be slurry (5.0ml) by adding ultrapure water. The behavior and influence of titanium dioxide on determination of As, Se and Sb were investigated in this experiment. The optimal conditions of a furnace for these elements were chosen as follows: pyrolysis temperature was 150 degrees C, and atomization temperature was 2300 degrees C. The optimal conditions of adsorption for As, Se and Sb on titanium dioxide were listed: pH 2.0 in sample solution; 10min of stirring time; and 20.0mg titanium dioxide. The difference of the chemical valence of each element had no effect on the recovery of each element at the same optimal conditions. Limits of detection (3sigma) for As, Se and Sb were found to be 0.21mugl(-1), 0.15mugl(-1) and 0.15mugl(-1), respectively, with enrichment rate of 20, when 20mul of slurry was injected into a Zr-coating tube. The proposed method was applied to tap water and river water.