一种危险液体混合物的拉曼光谱定性定量识别方法

危险液体混合物的拉曼光谱定性定量分析一直是现场应用难点，为解决该问题，分析了多种物质混合后拉曼光谱的峰位、峰值、峰型变化情况，选取拉曼光谱关键特征峰进行数学简化，构建了从混合物物质成分到混合物拉曼光谱的映射关系，该映射关系描述多种物质成分混合的混合物拉曼特征峰响应只和混合物中各成分本身拉曼特征峰响应以及各物质成分混合比例有关，各物质成分按混合比例贡献拉曼特征谱峰，共同形成最终的混合物拉曼光谱。由该映射关系求逆，可实现从采集到的混合物拉曼光谱计算出各物质成分的混合比例。基于此，设计了危险液体混合物成分定性定量识别方法，主要方法步骤包括，首先进行拉曼光谱数据采集，然后进行拉曼光谱数据处理并获得拉曼特征峰，再进行测试样品与数据谱库标准品的正反向特征峰匹配，如果正反向特征峰匹配系数都比较高，在满足一定阈值条件下，可认定测试样品是某种纯净物，如果不是纯净物，则进入混合物分析，通过拉曼光谱特征峰反向匹配系数筛选，确定混合物成分构成，混合物成分确定后再进行混合物成分比例计算，最终实现危险液体混合物定性定量分析。实验部分，选定丙酮、甲苯、三氯甲烷、乙醇及其混合物进行实验验证，当混合物样品是丙酮、乙醇两种成分按3∶7比例混合时，经拉曼光谱识别方法计算，混合成分计算值是丙酮占比0.245 7，乙醇占比0.706 0；当混合物样品是甲苯、三氯甲烷两种成分按3∶7比例混合时，经拉曼光谱识别方法计算，混合成分计算值是甲苯占比0.323 4，三氯甲烷占比0.763 0；当混合物样品是丙酮、甲苯、乙醇三种成分按4∶3∶3比例混合时，经拉曼光谱识别方法计算，混合成分计算值是丙酮占比0.795 9、甲苯占比0.303 5、乙醇占比0.287 5，实验结果表明，当危险液体混合物成分是两种或三种成分混合时，混合成分计算值基本和实际值吻合，应用危险液体混合物的拉曼光谱定性定量识别方法，可较准确的从拉曼混合光谱中解析出各混合物成分以及各成分在混合物中的比例，可以判断混合物每个拉曼特征谱峰都来自于哪个成分或哪些成分拉曼特征谱峰的混合，谱图解析结果良好，对危险液体混合物现场分析鉴别有较大应用价值。

Qualitative and Quantitative Identification of a Dangerous Liquid Mixture by Raman Spectroscopy

The qualitative and quantitative analysis of dangerous liquid mixtures by Raman spectroscopy has always been a difficult problem in field application. To solve this problem, this paper aoalyzes the changes of peak position, peak value and peak shape of Raman spectra after mixing, and innovatively constructs the mapping relationship from mixture components to mixture Raman spectroscopy. The mapping relation describes that the Raman characteristic peak response of the mixture is only related to the Raman characteristic peak response of each component and the mixing ratio of each component in the mixture. Based on the inverse matrix calculation, the mixing ratio of each component can be inversely deduced from the Raman spectra of the mixtures. So, in this paper the qualitative and quantitative identification method of dangerous liquid mixtures is proposed. The main steps include: First, collected Raman spectroscopy. Second, processed spectral data and obtained Raman characteristic peaks. Third, calculated the positive and negative matching coefficient between database standard samples and test samples. Finally, if the matching coefficients of both positive and negative characteristic peaks were high enough to satisfy certain threshold conditions, the test samples could be identified as a certain purity. If not a purity, the test samples would be analyzed as a mixture. In this part, the compositions whose negative matching coefficient of Raman spectra characteristic peaks is high will be determined as the compositions of the mixture, and proportion of mixture components is calculated. In the experimental part, acetone, toluene, trichloromethane, ethanol and their mixtures were selected to study. When the mixture was mixed with acetone and ethanol at a ratio of 3∶7, the calculated values of the mixtures by calculation using the method proposed in this paper were 0.245 7 for acetone and 0.706 0 for ethanol. When the mixture sample was composed of toluene and trichloromethane in a ratio of 3∶7, the calculated values of the mixtures were 0..323 4 for toluene, 0.763 0 for trichloromethane. When the mixture sample was composed of acetone, toluene and ethanol in a ratio of 4∶3∶3, the calculated values of the mixtures were 0.795 9 for acetone, 0.303 5 for toluene and 0.287 5 for ethanol. The results show that the calculated values of the mixed components were basically in agreement with the actual values, and the qualitative and quantitative identification method of Raman spectroscopy for dangerous liquid mixtures can accurately determine the composition of each mixture and the proportion of each component in the mixture from the mixed Raman spectroscopy when the components of dangerous liquid mixture are two or three. It has great application value for the field identification of dangerous liquid mixtures.