In this study, a temperature programmed oxidation-infrared (TPO-IR) technique was improved and applied in the analysis of sulfur occurrence and genesis in phosphate rock. Phosphate rocks from three regions (KYP, ZJP, and WAP) were selected for the detection of sulfur species by TPO-IR combined with XRD, SEM, EDS, and XPS characterization. TPO-IR results show that the total sulfur contents of the three phosphate rocks were 2.14% for KYP, 1.18% for ZJP, and 1.06% for WAP. In the low-temperature area (<1000°C), TPO-IR detected that both KYP and WAP contain FeS with a characteristic temperature of about 513°C and their contents were 9.22‰ and 0.64‰, respectively. In high-temperature areas (>1000°C), the TPO-IR curves suggest that sulfate is the main sulfur species in the three phosphate rocks. Typically, the characteristic temperature near 1070^oC belongs to MgSO₄, and the characteristic temperature near 1290°C belongs to CaSO₄. Due to the incomplete TPO-IR database of sulfur reference materials at present, it is not possible to assign all sulfur species in high-temperature areas. However, in a sense, this research provides theoretical basis and experimental support for the application of the TPO-IR technique for the detection of sulfur species in other solid minerals.

中文翻译：

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程序升温氧化-红外技术在磷矿含硫成因分析中的应用

本研究改进了程序升温氧化红外（TPO-IR）技术，并将其应用于磷矿中硫的赋存和成因分析。选择来自三个区域（KYP、ZJP 和 WAP）的磷酸盐岩石，通过 TPO-IR 结合 XRD、SEM、EDS 和 XPS 表征来检测硫物质。TPO-IR结果表明，三种磷矿的总硫含量分别为：KYP为2.14%、ZJP为1.18%、WAP为1.06%。在低温区（<1000℃），TPO-IR检测到KYP和WAP均含有FeS，特征温度约为513℃，含量分别为9.22‰和0.64‰。在高温区（>1000°C），TPO-IR曲线表明硫酸盐是三种磷矿中的主要硫物质。通常，特征温度接近 1070^o C属于MgSO ₄，1290℃附近的特征温度属于CaSO ₄。由于目前硫参考物质的TPO-IR数据库不完整，无法将高温地区的硫物种全部归类。但从某种意义上说，本研究为TPO-IR技术在其他固体矿物中硫物质检测中的应用提供了理论依据和实验支持。