Search

The aim of the paper is to examine the performance of molten carbonate fuel cell, which is supplied with a raw bioethanol, i.e. bioethanol which origins directly from fruit fermentation, without pre-treatment of fermentation products. The composition of raw bioethanol was precisely determined and then the impact of raw bioethanol on the degradation of molten carbonate fuel cells was examined. Steam to carbon ratio of the biofuel has been determined as 5.7 (in comparison to stoichiometry of reaction) which allowed for estimation of hydrogen production during steam reforming process taking place in the anode channel. The results in the form of current-voltage curve was obtained and compared with the same fuel cell fed with pure hydrogen, while the amount of hydrogen was defined as identical with the one after steam reforming of biofuel taking place in the nickel anode channel. Relevant literature studies were focused on the purified fuel or examination of the impact of individual components. Our study proved carbon deposition is not a problem, however solid particles contamination in fermentation product makes it impossible to use fuel cell fueled with fermentation product for longer periods, and prior to supplying fuel cell the bioethanol purification is required. A raw biofuel with its impurities did not have any impact on the anode and current collector surface from physical point of view, but Electrochemical Impedance Spectroscopy analysis shows visible increase of ohmic loses. • Homemade first generation bioethanol composition have been examined. • Manufactured bioethanol has been delivered directly to the MCFC anode without purification. • Performance of MCFC fueled with impure bioethanol has been investigated. • Effect of steam reforming for hydrogen generation and steam to carbon ratio were evaluated. • Pollution on the anode after cell operation was investigated with SEM and EIS. [ABSTRACT FROM AUTHOR]

This paper presents the results of research into improving the ionic conductivity of Molten Carbonate Fuel Cell by modifying the matrix material. So far, we have succeeded in using materials such as YSZ and SDC, but we are now trying to use powders based on Ba Na and TiO 2. These materials are characterized by their oxygen ion conductivity at elevated temperatures. A matrix of these materials was produced and used to build MCFCs. Based on the experiments carried out and the mathematical model of the fuel cell, the contribution of the oxygen ion conductivity to the total ionic conductivity was determined. • Research on oxygen ion conduction materials was performed. • BNT material has best oxygen ion conductivity parameters and was chosen for experiments. • New matrix made of BNT was manufactured. • Composite Li/K and BNT membrane was investigated under EIS and in fuel cell. • Model including ionic conductivity and tortuosity is presented and validated. [ABSTRACT FROM AUTHOR]

This paper reports the performance of a molten carbonate fuel cell (MCFC) fed directly with liquid fuels referenced against results with hydrogen fuel in experiments conducted by the research team. Alcohols have greater energy density than pure hydrogen in normal conditions and, if presented as biofuels, the MCFC can be deemed a renewable energy source. For evaluation purposes various alcohols occurring in standard conditions in the liquid state were used for electricity generation in the MCFC: methanol, ethanol, propanol, butanol and glycerol. Since these alcohols can be subjected to steam reforming when mixed with water in specific ratios, they can be delivered directly in the liquid state to the fuel cell, where hydrogen is released and used to produce electricity and heat. The alcohols were mixed with water in ratios of 1:2, 1:3, 1:4. The results were compared to the MCFC fed with pure hydrogen as a fuel. In terms of power referenced to hydrogen (100%), the maximums achieved were 78% for butanol, 80% for glycerol, 83% for propanol, 86% for ethanol and 93% for methanol in comparison to the same amount of hydrogen delivered to the fuel cell in ideal steam reforming situation. Threats such as carbon deposition on the fuel cell surface were also evaluated. • MCFC fed directly with various mixtures of alcohols and water have been studied. • The steam reforming of mixtures of alcohols and water generates energy. • Temperature and anode material provide the necessary conditions for steam reforming. • Maximum power compared to hydrogen fuel for various fuels ranges between 78 and 93%. • Carbon deposition in the anode channel of commercial units can be a problem. [ABSTRACT FROM AUTHOR]

The article presents a comparison of mathematical models of steam methane reforming. The analysis is divided into two parts. The first concerns the reforming process using separate steam reformers. The second part of the article compares models of steam methane reforming processes directly inside fuel cells. Due to the fact that the steam reforming process takes place at very high temperatures, internal steam reforming can only be carried out in high temperature fuel cells. Therefore, the second part of the article deals with molten carbonate fuel cells and solid oxide fuel cells powered by methane. In the case of both of fuel cells, the methane steam reforming may take place directly on the anodes of these electrochemical devices. The mathematical models (for both external and internal reforming) were compared based on available experimental data. In this analysis of mathematical models, particular attention was paid to the causes of discrepancies between the mathematical models and the experimental data. The steam reforming process is influenced by a number of different parameters such as: temperature, ratio of the amount of water vapor to carbon contained in the fuel (steam to carbon ratio), reaction time, presence of a catalyst, type of catalyst and many others. The models presented in this article were also compared in terms of taking into account various parameters that may affect the process of steam reforming. An attempt was also made to assess the accuracy of mathematical models. Unfortunately, for most of the equations considered in this article, numerical values for inaccuracies are not given or described as acceptable or minor. • Review of mathematical models of SMR. • The kinetics models of the steam methane reforming reaction. • Description of mathematical models for the molten carbonate fuel cell (MCFC). [ABSTRACT FROM AUTHOR]

In order to improve the energy efficiency of the Sabatier reactor-based power-to-gas process, molten carbonate fuel cells and solid oxide electrolyzers were installed instead of a conventional amine CO 2 capture system and a classical alkaline electrolyzer. The plant is a multi-module prototype with a nominal capacity of 50 kW consisting of two SOE-MCFC units. The system was commissioned in 2022. The article describes the theoretical basis. The initial assumptions that were formulated at the stage of preparing for the research investment, as well as the deviations from them that became the result of detailed design were presented. The developed startup and shutdown procedures, as well as the first results of pioneering research were shown. The trial operation of the system was intended to provide information on integrated SOE-MCFC module and its performance and efficiency. The basic barriers for market implementation and recommendations for future research were discussed. The optimal operating point for hydrogen production needed 35.8 kWh/kgH 2. Thus, electrical energy conversion to chemical energy efficiency is 93.9%. Flow preheating and electrical auxiliary heater power are not included. An MCFC at its ideal functioning point (around 4 kW el) outputs 5.4 kg/h of CO 2 separated. • Operational experience of upgraded novel P2G installation is reported. • A start-up procedure of MCFC-SOE tandem in proposed and experimentally verified. • Energy required for synthesis of a kilogram of hydrogen was 35.8 kWh/kgH 2. [ABSTRACT FROM AUTHOR]

This paper presents research on the impact of the material microstructure on the performance of Molten Carbonate Fuel Cells (MCFC). The study is motivated by the need to increase the operation time of MCFC stacks. As the MCFC stacks are mainly composed of porous materials, the paper shows the impact of the porosity on both fuel cell performance and degradation rate. The study is based on the mathematical model, validated through experiments with varying microstructure parameters, achieving an overall relative error of 8%. The study evaluated the performance of MCFC using anodes with different porosity and found that increasing anode porosity from 40% to 70% led to a nearly two-fold increase in maximum power density. However, from both the degradation test and polarization curves, the optimal level of porosity for the anode is around 55%. The porosity level at 55% ensures the highest catalytic surface of the electrodes and is a compromise between the mechanical properties of the electrode and its electrochemical properties. • New approach of 0D model of MCFC including materials microstructure influence is proposed. • The new model is prepared in MS Excel and Aspen HYSYS environments. • Experimental investigation for materials with predefined microstructire parameters was performed for model validation. • Variant analysis is presented for different porosity, tortuosity and constrictivity of MCFC anode. • An optimal scenario is suggested based on modleing results. [ABSTRACT FROM AUTHOR]

The paper aims to examine the possibility of improving the manufacturing process for MCFC cathodes. using noble, semi-precious, and rare earth metals sourced from waste electric and electronic equipment (WEEE). As MCFC components are not particularly sensitive to ceramic and metal impurities. The addition of noble metals recovered from WEEE as catalysts are economically justifiable. The reported experimental research revealed the positive impact of MCFC cathode fabricated with 20% recycled electronic scrap. Especially the cell with powder marked as 4/1 enjoyed much better performance operating at 550 °C than the reference cell. During the operation at a temperature of 650 °C, the cell with powder marked as 4/1 has almost the same performance as the reference cell, i.e., 1.01 V OCV and power density of 0.13 A/cm2. The cell with cathode with 4/2 powder has the worst performance – current density of 0.09 A/cm2 and OCV of 0.97 V. [Display omitted] • Rare earth elements separated by positive charge contains less cerium than separated by negative charge. • The maximum current densities and Open Circuit Values are similar as reference case for maximum gas flows. • The maximum current densities and Oper Circuit Voltages are better with additives for lower operational temperature. [ABSTRACT FROM AUTHOR]

It is proposed that dual conductive electrolytes have the potential to improve properties of MCFC by using oxygen ion conductors as matrix material, creating what is termed composite electrolyte. In this work we present the results of testing a novel type of electrolyte of molten carbonate fuel cell which consists of Yttria Stabilized Zirconia impregnated by Lithium/Potassium carbonates. Polarization curves were obtained for temperatures between 500 °C and 800 °C. Without very accurate measurements it is not easy to determine the additional electric charge provided by oxygen ions (O=). We made an attempt to build a mathematical model which takes into account both conductivities and, based on the model, estimated the ratio of electric charge provided by oxygen ions and carbonate ions. • We investigated double conducting electrolytes for Molten Carbonate Fuel Cell. • The investigation was done by both experimental and modeling methods. • We found small infuence done by ionic conductor. • The infunece is so small, that the results are not so evident. [ABSTRACT FROM AUTHOR]