Chemistry Department, Shahid Bahonar University of Kerman, Kerman, Iran.
Talanta. 2009 Nov 15;80(1):168-72. doi: 10.1016/j.talanta.2009.06.049. Epub 2009 Jul 1.
The present article reports on the application of modified multiwalled carbon nanotubes (MMWCNTs) as a new, easily prepared and stable solid sorbent for the preconcentration of trace rhodium ion in aqueous solution. Rhodium ions were complexed with 1-(2-pyridylazo)-2-naphthol (PAN) in the pH range of 3.2-4.7 and then the formed Rh-PAN complex was adsorbed on the oxidized MWCNTs. The adsorbed complex was eluted from MWCNTs sorbent with 5.0 mL of N,N-dimethylformamide (DMF). The rhodium in eluted solution was determined by flame atomic absorption spectrometry (FAAS). Linear range for the determination of rhodium was maintained between 0.16 ng mL(-1) and 25.0 microg mL(-1) in initial solution. Relative standard deviation for the 10 replicated determination of 4.0 microg mL(-1) of rhodium was +/-0.97%. Detection limit was 0.010 ng mL(-1) in initial solution (3S(bl), n=10) and preconcentration factor was 120. Sensitivity for 1% absorbance of rhodium (III) was 0.112 microg mL(-1). The sorption capacity of oxidized MWCNTs for Rh (III) was 6.6 mg g(-1). The effects of the experimental parameters, including the sample pH, flow rates of sample and eluent solution, eluent type, breakthrough volume and interference ions were studied for the preconcentration of Rh(3+). The proposed method was successfully applied to the extraction and determination of rhodium in different samples.
本文报道了改性多壁碳纳米管（MMWCNTs）作为一种新的、易于制备和稳定的固相吸附剂，用于预富集水溶液中痕量铑离子的应用。在 pH 值为 3.2-4.7 的范围内，铑离子与 1-(2-吡啶偶氮)-2-萘酚（PAN）络合，然后形成的 Rh-PAN 络合物被吸附在氧化的 MWCNTs 上。吸附的络合物用 5.0 mL N,N-二甲基甲酰胺（DMF）从 MWCNTs 吸附剂上洗脱。从洗脱液中用火焰原子吸收光谱法（FAAS）测定铑。在初始溶液中，铑的测定线性范围为 0.16 ng mL(-1)至 25.0 microg mL(-1)。在 4.0 microg mL(-1)的铑的 10 次重复测定中，相对标准偏差为 +/-0.97%。初始溶液中（3S(bl)，n=10）的检测限为 0.010 ng mL(-1)，预浓缩因子为 120。铑（III）的 1%吸光度的灵敏度为 0.112 microg mL(-1)。氧化 MWCNTs 对 Rh（III）的吸附容量为 6.6 mg g(-1)。研究了实验参数对 Rh(3+)预富集的影响，包括样品 pH 值、样品和洗脱液流速、洗脱液类型、穿透体积和干扰离子。该方法成功应用于不同样品中铑的提取和测定。
