Statistical modeling and performance optimization of a two-chamber microbial fuel cell by response surface methodology

Microbial fuel cell, as a promising technology for simultaneous power production and waste treatment, has received a great deal of attention in recent years; however, generation of a relatively low power density is the main limitation towards its commercial application. This study contributes toward the optimization, in terms of maximization, of the power density of a microbial fuel cell by employing response surface methodology, coupled with central composite design. For this optimization study, the interactive effect of three independent parameters, namely (i) acetate concentration in the influent of anodic chamber; (ii) fuel feed flow rate in anodic chamber; and (iii) oxygen concentration in the influent of cathodic chamber, have been analyzed for a two-chamber microbial fuel cell, and the optimum conditions have been identified. The optimum value of power density was observed at an acetate concentration, a fuel feed flow rate, and an oxygen concentration value of 2.60 mol m-3, 0.0 m3, and 1.00 mol m-3, respectively. The results show the achievement of a power density of 3.425 W m-2, which is significant considering the available literature. Additionally, a statistical model has also been developed that correlates the three independent factors to the power density. For this model, R2, adjusted R2, and predicted R2 were 0.839, 0.807, and 0.703, respectively. The fact that there is only a 3.8% error in the actual and adjusted R2 demonstrates that the proposed model is statistically significant

Mapping the field of microbial fuel cell: a quantitative literature review (1970–2020)

Microbial fuel cell (MFC) has received much attention in the last decade as a promising technology to simultaneously generate electricity and decontaminate wastewater. This study aims to quantitatively review the published literature on MFC, published in the period of 1970–2020, based on the Web of Science (WoS) database. For the first time in literature, a comprehensive quantitative review of MFC has been conducted by employing the technique of bibliometric and content analyses. A total of 11,397 publications have been retrieved from WoS, out of which 81.6% are research articles. The evaluation in the field of MFC has been mapped in various categories, such as publication history, publication distribution, subject category distribution, leading journals, leading countries and leading organizations in MFC research. Additionally, content analysis has been conducted to unearth the research trends in MFC; and some hot research topics in MFC have been spotted. Results depict that the period 2011–2020 has been the most appreciating era for MFC research, as it contributed 87% of the total publications. Among the subject categories, energy fuel and microbiology lead with contributions of 26.5% for each, butthe overall growth of the energy fuel category in the last decade has been the highest. Out of 1,147 journals publishing MFC research, Bioresource Technology is the leading one; and countries like China, USA and India are the main hub of MFC research with 26.47%, 16.95% and 7.69% contributions in publications, respectively. The hottest topics in MFC research are nanoparticles, catalysts, air electrodes, graphene electrodes, power enhancement, air cathode and nitrogen removal. Moreover, major research areas are engineering, energy fuels and biotechnology with each contribution 26.5% of the total publications

Manufacturing Strategies for Graphene Derivative Nanocomposites—Current Status and Fruitions

This review article highlights essential manufacturing strategies for the formation of graphene reinforced polymeric nanocomposites. For graphene reinforced thermoplastic, thermosetting and conducting matrix nanomaterials have been manufactured using solution casting, melt blending, in situ polymerization, electrospinning, 3D printing, and several other techniques. Solution processing has been well thought-out as an advantageous technique, relative to melt mixing, in terms of graphene dispersion in polymeric matrices. An in situ polymerization process has also been considered valuable to form homogeneously dispersed polymer/graphene nanocomposites having superior physical characteristics. Nevertheless, the manufacturing techniques for polymer/graphene nanocomposites have relative advantages and disadvantages to be considered for graphene-based nanocomposites. Moreover, numerous challenges need to be overcome to optimize the processing parameters for the fabrication of high-performance polymer/graphene nanocomposites

Modeling and Simulation of Solid Oxide Fuel Cell Integrated with Anaerobic Digester, Thermal Storage Unit and Solar Collector: A Net Zero Emission System

Energy production from clean and green sources is one of the eminent challenges to mankind. Overall, all industrial sectors contribute to CO2 emission, but the energy production sector is a major contributor. In recent years, CO2 emissions from the energy sector have increased by 1.7%. Therefore, the development of alternative energy production sources is a pivot for researchers. In this regard, the fuel cell has been a promising technology but still accompanied by the release of greenhouse gasses but relatively lower than that of fossil fuels. The integration of the fuel cell to the biogas has been a promising factor to reduce emissions. This study contributes to the same by producing a self-sustaining biogas-fuel cell multigeneration system for cold areas. Mathematical modeling of all complements of the system, i.e., anaerobic digester, solid oxide fuel cell, solar collector, and thermal storage system, is provided. MATLAB/Simulink environment is used for simulation of the system. The proposed system will use an anaerobic digester for methane production. Hence, produced methane will be used to power solid oxide fuel cell. The electricity of the fuel cell will power the residential place, and the thermal potential of the exhaust will be stored. In daylight, the solar thermal potential will be utilized for district heating. In the absence of solar light, stored thermal energy will be used for district heating and hot water supply. Additionally, the CO2 emitted from the system will not be released into the environment but stored for industrial purposes. The best area of application of the proposed system is cold areas such as Switzerland

Formulation Development of Mirtazapine Liquisolid Compacts: Optimization Using Central Composite Design

Mirtazapine is a tetracyclic anti-depressant with poor water solubility. The aim of this study was to improve the dissolution rate of mirtazapine by delivering the drug as a liquisolid compact. Central composite design (CCD) was employed for the preparation of mirtazapine liquisolid compacts. In this, the impacts of two independent factors, i.e., excipient ratio (carrier:coating) and different drug concentration on the response of liquisolid system were optimized. Liquisolid compacts were prepared using propylene glycol as a solvent, microcrystalline cellulose as a carrier, and silicon dioxide (Aerosil) as the coating material. The crystallinity of the formulated drug and the interactions between the excipients were examined using X-ray powder diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR), respectively. The dissolution study for the liquisolid compact was carried out as per FDA guidelines. The results showed loss of crystallinity of the mirtazapine in the formulation and was completely solubilized in non-volatile solvent and equally dispersed throughout the powder system. Moreover, drug dissolution was found to be higher in liquisolid compacts than the direct compressed conventional tablets (of mirtazapine). The liquisolid technique appears to be a promising approach for improving the dissolution of poorly soluble drugs like mirtazapine