本文提出了一种烟火药剂中高氯酸盐定性检测方法。将中性红用于高氯酸盐的定性检测；根据烟火药剂的组成特点对可能干扰检测结果的化学组分做了详细研究，提出了用0℃的10％KCl溶液洗涤样品排除干扰的步骤；对现有13类烟花爆竹用烟火药剂组成进行分析后，确立了用5％CaCl 2溶液脱附碳粉中高氯酸盐的前处理步骤。研究结果表明，方法检出限为100 ng· g-1。与以往的分析方法相比，本方法具有简单、实用、可靠等优点，可发展为烟花爆竹用烟火药剂中高氯酸盐定性检测的技术。%Perchlorate is a common oxidizing agent used in fireworks and firecrackers.The most popular way of qualitative detection of perchlorate is conventional chemical analysis method.However ,there are few qualitative detection methods which are specifically meant for perchlorates or perchloric acid up to now.In this paper ,a novel qualitative detection method on the application of perchlo-rate in pyrotechnic composition is proposed.The pyrotechnic composition is washed with ten percent potassium chloride solution at zero centigrade until it becomes colorless and basically neutral.Five percent calcium chloride solution is applied as an extractant and the mixture is heated and stirred over a boiling water bath for five minutes.The mixture is filtered when it is still hot.A few drops of cooled filtrate is applied to the neutral red reagent.A brown precipitation is formed immediately ,which is an indication of the presence of perchlorate salt deposits in the Pyrotechnic composition.There are three innovations in this method.Firstly,neutral red is used in the detection of perchlorate as an oxidation-reduction indicator ,which significantly reduce the analytical time because it selectively reacts with perchlorates very quickly.Secondly,based on the characteristics of pyrotechnic composition ,an in-depth re-search on the chemical components which could interfere with the result has been made , and an interference suppression step to clean the samples with potassium chloride solution has been proposed.Thirdly,by analyzing thirteen kinds of pyrotechnic composi-tions currently available ,it is established that calcium chloride solution can improve desorption of perchlorate from carbon as a pre -processing step.By testing three kinds of pyrotechnic compositions randomly picked , it is established that the minimum detection limit with this method is 100 ng/g.Comparing with other methods used ,the advantages of this method are simple ,convenient ,practi-cal,and reliable.It can be developed into a new qualitative detection technique of perchlorate in pyrotechnic compositions .
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