Agilent redesigns sulfur and nitrogen detectors
The Agilent 8355 sulfur chemiluminescence and 8255 nitrogen chemiluminescence detector provide integration of the gas chromatograph, detector and software for low-level analyses.
Food and beverage companies depend on precise sulfur and nitrogen testing to meet global regulations on pollution and product quality.
Use in food and beverage testing
Shanya Kane, Agilent vice president and general manager of the Gas Phase Separations Divisions, said sulfur has been associated with off-odor and off-taste in food and beverage products.
“The ability to detect sulfur in the final product is needed for quality assurance. In addition to final product, raw materials are also tested for sulfur compounds, such as beverage-grade CO2,” she told FoodQualityNews.
“In regards to nitrogen testing, this is applicable in both the petrochemical industry to quantifying different classes of nitrogen compounds as well as the consumer products, including foods, for the testing of nitrosamines.”
Kane said the redesign represents the first major advance in sulfur chemiluminescence detection in 25 years.
“Chemiluminescence technology was developed over 20 years ago to fulfill a purpose of being able to accurately detect low-level sulfur concentrations in hydrocarbon matrixes,” she said.
“Since then the applicability of the technology has been expanded as well as the inclusion of chemiluminescence detection for nitrogen.
“After taking a significant review of the product line, there were many components and manufacturing processes that could be leveraged from our gas chromatographs.”
Run time and detection capability
Time of analysis is dependent on the type of sulfur compounds attempting to be separated in the gas chromatograph.
Typical run time per sample can be from 15 to 30 minutes with each run offering detailed quantification for dozens of different sulfur compounds. Sensitivity of the detector can offer analysis of certain sulfur compounds at the sub-ppm range.
Kane said a liquid or gas sample is injected into a gas chromatograph.
“The sulfur compounds in the sample are separated and routed to the high-temperature reactor. The bound sulfur is converted to sulfur monoxide (SO), and then introduced to ozone,” she said.
“The reaction between the ozone and SO is a light-producing reaction, or a chemiluminescent reaction. The light is measured by the photomultiplier tube.”
Agilent said the redesigned detectors are easier to maintain due to a simplified burner design with 50% fewer components. The most common service routine, which used to take one hour, now takes 10 minutes.
The detectors are fully integrated with the Agilent 7890B gas chromatograph. They are also available as standalone units that can be connected to any gas chromatograph.
