Abstract The focus of this study was to assess the feasibility of time-gated Raman spectroscopy for stainless steel pickle liquor acid quantification. Pickle liquor is used for dissolving metal surface impurities during the pickling process. The pickle liquor samples consisted mainly of 11–89 g/L HNO3, 20–160 g/L H2SO4, 5–57 g/L HF and stainless steel residue. Raman peaks correlating with the different acids were identified in both aqueous and pickle liquor solutions. The linearity between Raman scattering intensity and acid concentration was studied. Multivariate PLSR calibration for pickle liquor HNO3, H2SO4 and HF quantification was also investigated. Time-gated Raman spectroscopy was found to be a promising technique for pickle liquor HNO3 and H2SO4 quantification.

中文翻译：

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时间门控拉曼光谱测定酸洗液中硝酸、硫酸和氢氟酸浓度的评价

摘要 本研究的重点是评估时间门控拉曼光谱用于不锈钢酸洗液酸定量的可行性。酸洗液用于在酸洗过程中溶解金属表面杂质。酸洗液样品主要由 11–89 g/L HNO3、20–160 g/L H2SO4、5–57 g/L HF 和不锈钢残留物组成。在水溶液和酸洗液溶液中都鉴定了与不同酸相关的拉曼峰。研究了拉曼散射强度和酸浓度之间的线性关系。还研究了酸洗液 HNO3、H2SO4 和 HF 定量的多变量 PLSR 校准。时间门控拉曼光谱被发现是一种用于酸洗液 HNO3 和 H2SO4 定量的有前途的技术。