Title: | Selective Detection of Volatile Organics in a Mixture Using a Photoionization Detector and Thermal Desorption from a Nanoporous Preconcentrator |
Author(s): | Prestage J; Day C; Husheer SLG; Winter WT; Ho WO; Saffell JR; Hutter T; |
Address: | "SensorHut Ltd., Vision Park, Cambridge CB24 9ZR, U.K. Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K. Alphasense Ltd., Sensor Technology House, 300 Avenue West, Skyline 120, Great Notley, Essex CM77 7AA, U.K. Materials Science and Engineering Program and Texas Materials Institute, The University of Texas at Austin, 204 E. Dean Keeton Street, Austin, Texas 78712, United States. Department of Mechanical Engineering, The University of Texas at Austin, Austin, Texas 78712, United States" |
DOI: | 10.1021/acssensors.1c02344 |
ISSN/ISBN: | 2379-3694 (Electronic) 2379-3694 (Linking) |
Abstract: | "The selective detection of individual hazardous volatile organic compounds (VOCs) within a mixture is of great importance in industrial contexts due to environmental and health concerns. Achieving this with inexpensive, portable detectors continues to be a significant challenge. Here, a novel thermal separator system coupled with a photoionization detector has been developed, and its ability to selectively detect the VOCs isopropanol and 1-octene from a mixture of the two has been studied. The system includes a nanoporous silica preconcentrator in conjunction with a commercially available photoionization detector (PID). The PID is a broadband total VOC sensor with little selectivity; however, when used in conjunction with our thermal desorption approach, selective VOC detection within a mixture can be achieved. VOCs are adsorbed in the nanoporous silica over a 5 min period at 5 degrees C before being desorbed by heating at a fixed rate to 70 degrees C and detected by the PID. Different VOCs desorb at different times/temperatures, and mathematical analysis of the set of PID responses over time enabled the contributions from isopropanol and 1-octene to be separated. The concentrations of each compound individually could be measured in a mixture with limits of detection less than 10 ppb(v) and linearity errors less than 1%. Demonstration of a separation of a mixture of chemically similar compounds, benzene and o-xylene, is also provided" |
Keywords: | "2-Propanol/analysis Chromatography, Gas *Nanopores Silicon Dioxide *Volatile Organic Compounds/analysis gas sensor nanoporous silica preconcentrator selective detection volatile organic compounds;" |
Notes: | "MedlinePrestage, Joshua Day, Coco Husheer, Shamus L G Winter, William T Ho, Wah O Saffell, John R Hutter, Tanya eng Research Support, Non-U.S. Gov't 2021/12/28 ACS Sens. 2022 Jan 28; 7(1):304-311. doi: 10.1021/acssensors.1c02344. Epub 2021 Dec 27" |