Filterrotationsspektrometer für den Nachweis von Ethen im ppb-Bereich

Ethylene is one of the most important phytohormones in the ripening process of climacteric fruit. In this context, the amount of emitted ethylene can provide information on the current ripening phase of these fruit. Therefore, ethylene sensors can be used for the implementation of novel logistic processes, such as the First-Expired-First-Out-Process (FEFO), in the supply chain of climacteric fruits. This work presents the current state of the development of a low-cost filter rotation spectrometer for detection of ethylene in the climacteric ripening phase of fruit. The spectrometer is based mainly on commercial components, which are also used in classical nondispersive infrared sensors (NDIR). A model-based evaluation of the measured spectra has significantly improved the stability of our first laboratory prototype compared to classical NDIR sensors. In combination with an optimized optical long path cell, a detection limit of 150 ppb could be reached. In addition, simulations have shown that this principle is suitable for the quantitative determination of the potential cross-sensitivity gases ammonia and carbon dioxide. By combining the simulation and measurement results, a detection limit of 0.19 % for carbon dioxide and 62 ppb for ammonia is expected