FT-Raman instruments have been used for laboratory analysis in myriad industries since they were introduced in the 1980s. These industries include finished polymers, pharmaceuticals and certain specialty chemicals. Raman instruments have not been as successful for process measurements outside the laboratory due to Raman’s technical limitations, such as sampling issues and fluorescent interferences, according to Kaiser Optical Systems’ marketing manager, Ian Lewis. Dr. Lewis said that these issues are addressed with the recently introduced RamanRxn2 1000 Raman analyzer. “It’s a unique product, offering reaction-monitoring Raman capability at long wavelength,” he said. “It provides the fluorescence suppression of a laboratory FT-Raman system with the interface capability of a dispersive Raman instrument.”

Dr. Lewis told IBO that for certain applications, in which Raman cannot be used to monitor in situ, the analyzer can be used, including early-phase “dirty” crystallizations, biofuel manufacturing, food and beverages, heavy hydrocarbons, polyurethanes and some colorants/pigments. These applications exhibited fluorescence too intense to be addressed with 785 nm excitation, the most universal wavelength for petrochemical and pharmaceutical Raman applications, according to Kaiser Optical Systems. The analyzer uses 1,000 nm excitation for a compromise between fluorescence rejection and detection sensitivity. “It allows Kaiser to address areas which have not been well served by in situ Raman in the past,” Dr. Lewis said.