Peer-Reviewed Journal Details
Mandatory Fields
Memon, S.F., M.M Ali, J. T Pembroke, B S. Chowdhry E Lewis
Ieee Transactions On Instrumentation And Measurement
Measurement of Ultra Low Level Bio-Ethanol Concentration for Production using Evanescent-Wave based Optical Fibre.
Optional Fields
Ethanol, Cyanobacteria, Sensor, Optical Sensor
           We report a U-bend plastic optical fiber (POF) sensor for measuring ultralow concentration of ethanol corresponding to the initial bioethanol production rate by cyanobacteria, i.e., 0.1-0.5 gL⁻¹ day⁻¹. This production rate corresponds to 0.00499-0.0499 %wt of ethanol in total solution in terms of weight percent concentration. Refractive indices for these minute ethanol concentration values are not available in the literature hence mathematical estimation of the refractive indices for the ethanol-water solutions in this concentration range is demonstrated. The sensing principle is based on optical fiber-based evanescent wave absorption. Parameters affecting the response of an evanescent wave absorption sensor are analyzed for the intended concentration range of ethanol. Experimental results using the U-bend evanescent wave POF sensor are also presented for ethanol-water solutions having refractive indices corresponding to the bioethanol production rate. The excellent repeatability of the measurement is established and these real-time measurements show that sensor has a sensitivity of 817.76 O.D/RIU (O.D refers to optical density, unit of absorbance) with a 99.76% linearity. The limit of detection of the sensor is 9.2 x 10⁻⁷ RIU. It is also proved using refractive index calculations of ethanol-water solutions that the sensor exhibits a resolution of 10⁻⁷ RIU. The sensor of this investigation, therefore, represents a potential solution for online and real-time monitoring of the production of biofuels even at the very low-level initial concentration of product.            
ISSN: 1557-9662
Grant Details