Real-Time Speciation of Ethylbenzene from the Xylenes Using Direct MS

Real-Time Speciation of Ethylbenzene from the Xylenes Using Direct MS

Mark J. Perkins,¹ Vaughan S. Langford²

¹Anatune Ltd, Girton Road, Cambridge, CB3 0NA, United Kingdom \ ²Syft Technologies Ltd, 3 Craft Place, Christchurch 8024, New Zealand

Direct mass spectrometry (DMS) techniques struggle to speciate ethylbenzene from the xylene isomers, yet increasingly regulators are imposing different emission and exposure limits for these compounds. This application note describes a significant breakthrough for DMS, because selected ion flow tube mass spectrometry (SIFT-MS) readily achieves direct, real-time speciation of the xylenes from ethylbenzene.

Resolution of ethylbenzene from the xylenes is important when regulators impose different emission or exposure limits, as is the case for occupational exposure limits in the European Union (timeweighted averages of 100 and 50 ppm, respectively). Direct mass spectrometry techniques traditionally struggle to distinguish these isomers, so measurement has been reported as a total concentration. In this application note we apply the SIFT-MS technique to achieve direct, real-time speciation of the xylenes from ethylbenzene.