Study On The Analysis Method Of Thallium In Water And Its Application In Environmental Samples

Thallium is a highly toxic and study lacking metal element. The hazard of thallium in such aspects as drinking water becomes more and more noticeable with increasing awareness of the public in environmental protection. Aim at more and more seriously environmental thallium pollution problems, this paper studied the analysis methods of thallium in water. The inductively coupled plasma atomic emission spectrometry(ICP-AES) to determinate the content of thallium in waste water was established. The platform graphite furnace atomic absorption spectrometry(GFAAS) and inductively coupled plasma mass spectrometry(ICP-MS) to detect thallium content were improved. These methods were used to guide emergency monitoring of thallium pollution in the water of a watershed and in waste water of the enterprises in a Province. The details are summarized as follows:1. Determination of thallium in surface water with GFAAS. On the basis of the ordinary AAS, the content of thallium in surface water was determined using Pd(NO3)2/Mg(NO3)2 mixed solution as the matrix modifier and platform graphite tube as the atomizer. The standard curve with good linear relationship was obtained and the limit of detection was as low as 0.02 μg/L. The determination results had no statistical difference compared with that obtained from expensive ICP-MS method.2. The determination of thallium content in surface water using ICP-MS. An analysis method for detection of the content of thallium in surface water with ICP-MS was established. The limit of detection was 0.003 μg/L and the best measured medium was 0.5 % of HNO3 solution. Furthermore, except the Barium of 105 times, Lithium of 5000 times and Tin of 1000 times had some interferences with the determination of 1.0 μg/L of thallium solution, the other common coexisting elements had no significant effects on the measurement of thallium in surface water.3. Determination of thallium in waste water using ICP-AES. A new method was developed for the detection of thallium in waste water using ICP-AES method. The limit of detection of thallium was 22 μg/L, the optimal wavelength was 190.8 nm, the suboptimal wavelength was 377.5 nm and the measured medium was 0.5 % of HNO3 solution. Common coexisting elements, except Calcium of 100 times, had no interference on the determination of thallium in waste water.4. Emergency monitoring of thallium pollution in environment. Administrative departments provided decisive and correct decisions for this thallium emergency disposal. The thallium contamination of a large area had been effectively controlled in short term and it became a successful example for heavy metal pollution emergency disposal.5. Monitoring for pollution sources of thallium in environment. The results indicate that the thallium pollution was mainly the results of related enterprises discharged waste water, not caused by high background values.