Investigation of Direct-Fed Solid Oxide Fuel Cell Fueled by Upgraded Bio-Oil Extracted from Olive Waste Pyrolysis: Part 2: Analysis of Electrochemical Behavior and Cell Performance

Abstract

In this paper, we propose the first demonstration of the flexibility of operating directly Intermediate Temperature Solid Oxide Fuel Cell (IT-SOFC) with liquid biofuels for sustainable clean power generation. Biofuel used in this part is prepared through an upgrading process of bio-oil obtained from olive mill wastewater sludge detailed in part 1 and demonstrated a successful improvement in physicochemical properties. Cell electrochemical polarization behavior, stability and internal decomposition of upgraded bio-oil over the Ni-SDC anode at different operating conditions such as temperatures and feed flow rates were deeply investigated. Results showed that IT-SOFC is able to convert the upgraded bio-oil to electricity at viable power densities (230 mW cm−2 at 750 °C) which is majorly related to the production of reactive fuels (H2, CO, CH4) from upgraded bio-oil cracking over Ni-based catalyst. Several side reactions may also occur over anode. Reverse Boudouard reaction is the main reaction reducing deposits as it forms. Bio-oil upgrading leads to a promising stability with limited carbon deposits (1.35 wt %) at 750 °C.