Combined amperometric/field-effect sensor for the detection of dissolved hydrogen

Abstract

Real-time and reliable monitoring of the biogas process is crucial for a stable and efficient operation of biogas production in order to avoid digester breakdowns. The concentration of dissolved hydrogen (H-2) represents one of the key parameters for biogas process control. In this work, a one-chip integrated combined amperometric/field-effect sensor for monitoring the dissolved H-2 concentration has been developed for biogas applications. The combination of two different transducer principles might allow a more accurate and reliable measurement of dissolved H-2 as an early warning indicator of digester failures. The feasibility of the approach has been demonstrated by simultaneous amperometric/fieldeffect measurements of dissolved H-2 concentrations in electrolyte solutions. Both, the amperometric and the field-effect transducer show a linear response behaviour in the H-2 concentration range from 0.1 to 3% (v/v) with a slope of 198.4 +/- 13.7 nA/% (v/v) and 14.9 +/- 0.5 mV/% (v/v), respectively. (C) 2012 Elsevier B. V. All rights reserved.