ONLINE MEASUREMENTS USING MASS-SPECTROMETRY

The purpose of this report is to provide background information and op erating principles about process mass spectrometry to process operator s. Those people who make it their business to operate and maintain che mical processes will understand the difficulty in producing a good qua lity product on a day-to-day basis. The use of real-time process analy sis and control has been useful in establishing and maintaining optimu m operating parameters so that the potential for human error may be re duced. Real-time data allows the process operators to make decisions t o immediately correct for a problem during the process so that the pro duct quality can be preserved. Process mass spectrometers have been us ed in Dow Chemical for approximately 20 years in process control appli cations. In spite of this early start, the number of applications for process mass spectrometers in Dow has been relatively few. More recent ly, there is renewed interest in using mass spectrometers for process analysis because of their speed and multicomponent analysis capabiliti es. As a result, the number of process mass spectrometers in Dow North America has more than doubled in the last five years. This paper pres ents the basic function of process mass spectrometry and compares proc ess mass spectrometry with its main competitors, namely process gas ch romatography and process infrared spectrometry.