Ahilan, Vignesh
Loading...
4 results
Now showing 1 - 4 of 4
- Some of the metrics are blocked by yourconsent settings
Item type:Publication, Tailoring hydrophilic and porous nature of polysiloxane derived ceramer and ceramic membranes for enhanced bioelectricity generation in microbial fuel cell(Springer, 2019-06-28); ; ; ; Selection of proton conducting membrane is currently a key factor that decides the performance of microbial fuel cell (MFC). Uniaxial pressed polysiloxane-derived ceramer and ceramic membrane with proton conducting fillers like montmorillonite and H3PMo12O40/SiO2 were applied for the first time as separator in MFC. Here, we present a series of polymer-derived ceramic membranes tailored based on pyrolysis temperature and filler addition, in which ion exchange capacity, cation transport number, and oxygen permeability are influenced through the hydrophilic and porous structural property. The maximum power density of MFC with polysiloxane-derived ceramer membrane modified with 20 wt% montmorillonite and 10 wt% H3PMo12O40/SiO2 reached a value of 5.66 W m−3, which was four times higher than that with non-modified polysiloxane-derived ceramer membrane. Furthermore, the specific power recovery per unit cost of the membrane was found to be 2-fold higher than MFC using polymeric Nafion membrane. In contrast, MFC with polysiloxane-derived ceramic membrane modified with 20 wt% montmorillonite delivers 1.2 times lower power density (4.20 W m−3) than that with non-modified macroporous polysiloxane-derived ceramic membrane. Hence, the findings demonstrated that tailoring the hydrophilic and porous structure of the ceramic membrane is a new and promising approach to enhance the performance of MFC.journal article116 132 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Microbial fuel cell performance of graphitic carbon functionalized porous polysiloxane based ceramic membranes(Elsevier, 2019-06-25); ; ; ; Proton-conducting porous ceramic membranes were synthesized via a polymer-derived ceramic route and probed in a microbial fuel cell (MFC). Their chemical compositions were altered by adding carbon allotropes including graphene oxide (GO) and multiwall carbon nanotubes into a polysiloxane matrix as filler materials. Physical characteristics of the synthesized membranes such as porosity, hydrophilicity, mechanical stability, ion exchange capacity, and oxygen mass transfer coefficient were determined to investigate the best membrane material for further testing in MFCs. The ion exchange capacity of the membrane increased drastically after adding 0.5 wt% of GO at an increment of 9 fold with respect to that of the non-modified ceramic membrane, while the oxygen mass transfer coefficient of the membrane decreased by 52.6%. The MFC operated with this membrane exhibited a maximum power density of 7.23 W m-3 with a coulombic efficiency of 28.8%, which was significantly higher than the value obtained using polymeric Nafion membrane. Hence, out of all membranes tested in this study the GO-modified polysiloxane based ceramic membranes are found to have a potential to replace Nafion membranes in pilot scale MFCs.journal articleBand:129125 160 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Porous polymer derived ceramic (PDC)-montmorillonite-H3PMo12O40/SiO2 composite membranes for microbial fuel cell (MFC) applicationCeramic membranes can serve as viable alternatives to the less mechanically stable polymeric membranes utilized in microbial fuel cells (MFCs). In this work, a series of polymer-derived ceramic (PDC) proton exchange composite membranes with large ion exchange capacity (IEC) values, high cation transport numbers, and low oxygen diffusion coefficients have been synthesized at various pyrolysis temperatures using a pressing technique. These materials were composed of a polysiloxane matrix mixed with proton-conducting fillers such as montmorillonite and H3PMo12O40/SiO2 at different ratios. By tuning the average pore sizes of the membranes between 0.1 and 1 µm and their hydrophilic/hydrophobic characteristics, the maximum IEC of 0.6072 mequiv/g and cation transport number of 0.6988 were obtained, which is 67% and 72% of polymeric nafion performance, respectively. In addition, the minimal oxygen mass transfer coefficient achieved by this approach was equal to 5.62 × 10−4 cm/s, which is very close to the commercial nafion membrane value. The fabricated PDC composite membranes meet all the essential criteria required for their use in MFC applications and represent a high potential to overcome limitations of polymeric membrane.journal articleBand:44Heft:16113 91 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Porous polymer derived ceramic membranes for bioelectricity generation and wastewater treatment(2020-02-26); ; ; The pollution caused by the use of conventional energy sources represents a serious threat to the existing global ecological system, which stimulates the ongoing search for alternative environmentally safe biochemical energy sources that are able to fulfill the future energy demand. The microbial fuel cell (MFC) technology is one of such alternative energy resources conceptualizing the waste-to-energy principle, which can be used for wastewater treatment with simultaneous recovery of bio-energy using microorganisms as biocatalysts. The Membrane bioreactor (MBR) is another promising technology for wastewater treatment, it is combination of activated sludge process and membrane filtration. The integration of these two technologies will be an efficient one for wastewater treatment and bioelectricity generation. The selection of proton conducting and water permeable membrane are currently the key factors that decide the performance of microbial fuel cell (MFC) and Membrane bioreactor (MBR), respectively. Porous Polymer derived ceramics (PDC) membranes were prepared by a simple uni-axial hydraulic pressing technique, using polysiloxane as a precursor and proton conducting materials as fillers. The ceramic membranes produced have tailorable surface characteristics and uni-modal pore size distribution in a range between 0.1 and1 µm. These porous ceramic membranes are designed for MFC and MBR applications that involve proton ion diffusion and water permeability. The ceramic membrane properties were tailored by addition of filler materials such as cation exchange material, graphitic carbon and hygroscopic material. The cation exchange materials are montmorillonite and H3PMo12O40/SiO2 filler used in the first approach with variable pyrolysis temperature (400 -1000 oC). This results in high MFC performance using cation exchange filler functionalized ceramer membrane (pyrolysed at 400 oC). In the second approach, functionalized ceramic membranes with different weight percentage of graphene oxide and multiwall carbon nanotube pyrolyzed at 1100 oC, were prepared and showed a high MFC performance specially for functionalized ceramic membranes with 0.5 wt.% graphene oxide. Functionalized with ceramic membrane with hygroscopic fillers such as SiO2 (as particle), SiO2 (derved from TEOS) and TiO2 were pyrolysed at 1100 oC, which results in high MFC performance and water permeability for MBR application by using ceramic membrane functionalized with 15 wt% TiO2. In all the approaches, the physical characteristics, such as porosity, hydrophilicity, mechanical stability, ion exchange capacity, and oxygen mass transfer coefficient, of the membranes were measured to identify the suitability of the membrane material for further testing in MFC and MBR systems. Finally, the 20 liter capacity pilot scale integrated MFC and MBR system were studied using a ceramic membrane pyrolysed at 1000 oC and reported the bioelectricity generation and wastewater treatment efficiency.doctoral thesis317 198