Method for purifying and analyzing chlorine isotope in complex matrix sample

Abstract

The invention provides a method for purifying and analyzing chlorine isotope in a complex matrix sample. The method comprises the following steps of A, removing organic matters in a sample and purifying the sample; B, removing inorganic interferent from the sample and carrying out separation and purification: B-1, collecting high-purity samples; B-2, selecting an ion chromatographic separation column, and adjusting the inhibition current of a suppressor to be 10-50mA greater than or above of the concentration recommended value of the corresponding eluent, and carrying out gradient elution; B-3, enabling a solution to pass through a microporous filter membrane to be filtered and then performing sampling and sample collection; B-4, carrying out concentration: baking the collected sample on aheating plate to remove a part of moisture; and B-5, enabling the distillate to pass through a cesium cation exchange resin column Cs column to obtain a high-purity cesium chloride solution; and C, carrying out thermal ionization mass spectrometry measurement and correction. The method disclosed by the invention is simple and convenient to operate and high in feasibility; the purification efficiency is extremely high; the purification effect of being close to 100% can be achieved by single purification; and the test background is low, the precision is high, and the method is suitable for batch sample test.

Description

technical field [0001] The invention belongs to the field of stable isotope analysis, and specifically relates to a method for purifying and analyzing chlorine isotopes in complex matrix samples, which can be applied to high-precision analysis of inorganic chlorine isotope ratios in seawater, river water, groundwater, pore water and sewage. Background technique [0002] Chlorine contains two stable isotopes in nature, which are 35 Cl and 37 Cl. The change of chlorine isotope has important indication significance for the study of geochemical cycle of chlorine element, seawater intrusion, groundwater recharge and excretion, paleoclimate change, characteristics of evaporated salt, formation of mineral deposit, degradation of chlorinated organic matter, etc. Compared with elements such as carbon, hydrogen, and oxygen, chlorine is less prone to isotope fractionation because of its stable physical and chemical characteristics. but due to 35 Cl and 37 The relatively large mass...

AI Technical Summary

Problems solved by technology

In order to better solve the problem of these two types of matrix interference in isotope testing, the present invention discloses a chlorine isotope purification method based on improved ion chromatography separation technology, and is aimed at complex matrix water bodies such as groundwater, surface water, river water, and sewage. samples, develop a total solution

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