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Determination of arsenic in pure aluminum by inductively coupled plasma atomic emission spectrometry was interfered by aluminum matrix. The experiment showed that when the mass concentration of Al was greater than or equal to 5 000 times the As in the test solution, the measurement error was greater than 5%. In order to eliminate the interference, strong acid cation exchange fiber (SACEF) was used as solid phase extraction agent to adsorb Al(3+). The extraction conditions included amount of SACEF, extraction time, temperature and pH were investigated. The optimal extraction conditions were that 0.9000 g SACEF was used to extract the aluminum from the sample solution of pH 2.0 at 55 °C for 5 min with the ultrasonic assist, and in this case, the arsenic in the form of arsenic acid was not extracted and left in the solution for the determination. The results showed that after treating 10. 00 mL test solution containing 1.00 µg arsenic and 20.0 mg aluminum, arsenic did not lose. The mass concentration of residual aluminum in the raffinate was about 2,000 times the As, which had not interfered the determination of arsenic. The detection limit (3 s) was 0.027 µg · mL(-1) and quantification limit (10 s) was 0.0091 µg · mL(-1). The proposed method was successfully applied to the separation and determination of arsenic in the synthetic samples, the aluminum cans and the barbecue aluminum foil. Recovery was in the range of 98.3%-105% and RSD (n = 3) was in the range of 0.1%-4.3%. The results showed that the content of arsenic in the aluminum cans and the aluminum barbecue foil was below the limited value of national standard (GB/T 3190-2008).

Three-dimensional fluorescence parameters can reflect classification, properties and content change of pollutants in wastewater treatment. In the present paper, by using three-dimensional fluorescence characteristic analysis, comparative analysis of conventional organic pollutants such as COD, TN and TP, and three dimensional fluorescence spectrum analysis, the classification and content of dissolved organic pollutants were identified. We studied fluorescence spectra, fluorescence peak (R. U.), fluorescence index (FI), humification index (HIX) of DOM's four components in the entrance and effluent water and interstitial water, as well as the correlation between these four components and COD, TN and TP. The results showed that the position and intensity of the characteristic fluorescence peak center changed significantly before and after sewage treatment, indicating that the relative composition and content of the organic wastewater varied with wastewater treatment. Furthermore, the test results presented that humic-like composition was not degraded significantly, while protein-like composition was degraded significantly. And the protein-like component and COD, TN and TP presented significant positive correlation. This paper analyzed the fluorescence characteristics changes of dissolved organic matter in sewage treatment by using three-dimensional fluorescence spectrometry, and discussed the feasibility of three-dimensional fluorescence technique applied for description of dissolved organic pollutant degradation rule in the wastewater treatment process.