A novel approach was developed for the determination of ultratrace amounts of copper in water samples by using electrothermal atomic absorption spectrometry （ETAAS） after cloud point extraction （ CPE ）. 1-（ 2-Pyr...A novel approach was developed for the determination of ultratrace amounts of copper in water samples by using electrothermal atomic absorption spectrometry （ETAAS） after cloud point extraction （ CPE ）. 1-（ 2-Pyridylazo ） -2- naphthol was used as the chelating reagent and Triton X-114 as the mieellar-forming surfactant. CPE was conducted in a pH 8. 0 medium at 40 ℃ for 10 rain. After the separation of the phases by contrifugafion, the surfactant-rieh phase was diluted with 1 mL of a methanol solution of 0. 1 mol/L HNO3. Then 20μL of the diluted surfactant-rieh phase was injected into the graphite furnace for atomization in the absence of any matrix modifier. Various experimental conditions that affect the extraction and atomization processes were optimized. A detection limit of 5 ng/L was obtained after preconeentration. The linear dynamic range of the copper mass concentration was found to be 0-2.0 ng/mL, and the relative standard deviation was found to be less than 3. 1% for a sample containing 1.0 ng/mL Cu （ Ⅱ ）. This developed method was successfully applied to the determination of uhratraee amounts of Cu in drinking water, tap water, and seawater samples.展开更多
An experimental investigation was presented on the separation of Cu（Ⅱ）, Zn（Ⅱ）, and Cd（Ⅱ） from a rich sulfate leachate of zinc slag by solvent extraction. The results of orthogonal experiments indicate that LI...An experimental investigation was presented on the separation of Cu（Ⅱ）, Zn（Ⅱ）, and Cd（Ⅱ） from a rich sulfate leachate of zinc slag by solvent extraction. The results of orthogonal experiments indicate that LIX 984N is highly selective and very efficient in the extraction of Cu（Ⅱ）, and the analysis of variance indicates that the sequence of parameters according to their influence on the separation efficiency is phase ratio 〉 LIX 984N concentration 〉 pH value 〉 extraction time. The optimal condition for copper extraction is obtained as 25% of LIX 984N concentration, 7 rain of extraction time, 3：2 of phase ratio O/A, and pH = 1.7. The separation of Zn（Ⅱ） and Cd（Ⅱ） was performed after the copper extraction from the raffinate. Comparative analysis of the separation with di-2-ethylhexyl phosphoric acid （D2EHPA）, D2EHPA-tributyl- phosophate （TBP） synergistic extracting system, and 2-ethylhexyl phosphonic acid mono 2-ethylhexyl ester （HEHEHP） was made at pH = 2.0. It is demonstrated that the extraction efficiency with D2EHPA is improved after being saponified by sodium hydroxide, and D2EHPA-TBP synergistic extracting, as well as HEHEHP, has a superior selectivity to Zn（Ⅱ） over Cd（Ⅱ）.展开更多
基金the Analysis and Testing Foundation of Zhejiang Province(No 04045)
文摘A novel approach was developed for the determination of ultratrace amounts of copper in water samples by using electrothermal atomic absorption spectrometry （ETAAS） after cloud point extraction （ CPE ）. 1-（ 2-Pyridylazo ） -2- naphthol was used as the chelating reagent and Triton X-114 as the mieellar-forming surfactant. CPE was conducted in a pH 8. 0 medium at 40 ℃ for 10 rain. After the separation of the phases by contrifugafion, the surfactant-rieh phase was diluted with 1 mL of a methanol solution of 0. 1 mol/L HNO3. Then 20μL of the diluted surfactant-rieh phase was injected into the graphite furnace for atomization in the absence of any matrix modifier. Various experimental conditions that affect the extraction and atomization processes were optimized. A detection limit of 5 ng/L was obtained after preconeentration. The linear dynamic range of the copper mass concentration was found to be 0-2.0 ng/mL, and the relative standard deviation was found to be less than 3. 1% for a sample containing 1.0 ng/mL Cu （ Ⅱ ）. This developed method was successfully applied to the determination of uhratraee amounts of Cu in drinking water, tap water, and seawater samples.
文摘An experimental investigation was presented on the separation of Cu（Ⅱ）, Zn（Ⅱ）, and Cd（Ⅱ） from a rich sulfate leachate of zinc slag by solvent extraction. The results of orthogonal experiments indicate that LIX 984N is highly selective and very efficient in the extraction of Cu（Ⅱ）, and the analysis of variance indicates that the sequence of parameters according to their influence on the separation efficiency is phase ratio 〉 LIX 984N concentration 〉 pH value 〉 extraction time. The optimal condition for copper extraction is obtained as 25% of LIX 984N concentration, 7 rain of extraction time, 3：2 of phase ratio O/A, and pH = 1.7. The separation of Zn（Ⅱ） and Cd（Ⅱ） was performed after the copper extraction from the raffinate. Comparative analysis of the separation with di-2-ethylhexyl phosphoric acid （D2EHPA）, D2EHPA-tributyl- phosophate （TBP） synergistic extracting system, and 2-ethylhexyl phosphonic acid mono 2-ethylhexyl ester （HEHEHP） was made at pH = 2.0. It is demonstrated that the extraction efficiency with D2EHPA is improved after being saponified by sodium hydroxide, and D2EHPA-TBP synergistic extracting, as well as HEHEHP, has a superior selectivity to Zn（Ⅱ） over Cd（Ⅱ）.
