School of Science and Technology, Chemistry Division, University of Camerino, 62032 Camerino, Italy.
Automa Srl, 60131 Ancona, Italy.
Sensors (Basel). 2021 Nov 15;21(22):7575. doi: 10.3390/s21227575.
The presence of benzene and similar aromatic compounds in civil environments is due to anthropic actions but also to natural sources. Natural gas consists of a gas mixture where benzene and related compounds are usually presents. Thus, the detection of these compounds in natural gas pipelines is of the utmost importance as well as the control of the concentration level, which must remain below the limits consented by law. In this regard, it is of striking interest to engineer devices able to detect these compounds by automatic and continuous remote control. Here, we discuss the application of an optical device designed for the measurement of sulfured odorizing agents in natural gas pipelines aiming at the detection and the measurement of benzene, toluene, and xylenes (BTX) in the same contexts. The instrument consists of a customized UV spectrophotometer connected to an automatic control system able to provide in-field detections of BTX through a continuous and remote check of the gaseous mixture. Relatively to benzene, the instrument is characterized by values of LOD (level of detection) and LOQ (level of quantification) equal to 0.55 and 1.84 mg/Sm3, respectively. Similar limits are found for toluene and xylenes (LOD of 0.81, 1.05, 1.41, and 1.00 mg/Sm3 for toluene, meta-, ortho-, and para-xylene, respectively).
民用环境中苯和类似芳香族化合物的存在不仅是人为活动的结果，也是自然来源的结果。天然气由一种气体混合物组成，其中苯和相关化合物通常存在。因此，检测天然气管道中这些化合物的存在以及控制浓度水平至关重要，浓度水平必须保持在法律允许的限度以下。在这方面，设计能够通过自动和连续远程控制来检测这些化合物的工程设备具有重要意义。在这里，我们讨论了一种用于测量天然气管道中含硫加臭剂的光学设备的应用，该设备旨在检测和测量相同环境中的苯、甲苯和二甲苯（BTX）。该仪器由一台定制的紫外分光光度计组成，连接到一个自动控制系统，能够通过对气体混合物的连续和远程检查，提供现场 BTX 检测。相对于苯，该仪器的检测限（LOD）和定量限（LOQ）分别为 0.55 和 1.84mg/Sm3。甲苯和二甲苯也发现了类似的限值（甲苯的 LOD 为 0.81、1.05、1.41 和 1.00mg/Sm3，分别为间、邻、对二甲苯）。
