Chaiwat Prapainainar

Feasibility Study of Bio-Hydrogenated Diesel (BHD) Production: A Case Study in Thailand

It founded that crude palm oil, CPO, could be changed to Bio-hydrogenated Diesel, BHD, which has a potential to replace the petroleum-derived diesel. Therefore, techno-economic feasibility of BHD production for Thailand was studied with a capacity of 1 million liters per day (MLD) of BHD. In this work, a conceptual design of BHD process was developed by using process simulator, ASPEN Plus. Calculation of mass and energy balance, equipment sizing and cost estimation in five major unit operations were performed. The total capital investment was calculated and used for economic analysis to estimate the return on investment, price value and payback period. The results showed that total capital investment cost was 174.34 millions USD with 1 MLD of BHD, PBP was 5 years with 17.02% ROI. BHD price of 1.16 USD/L.

Synthesis and Characterization of Silaned-Graphene Oxide-Mordenite Grafting

The grafted materials of silaned-graphene oxide-mordenite (s-GO-MOR) were synthesized by grafting graphene oxide (GO) sheets to acid-treated mordenite and followed by functionalization with silane. GO sheets were prepared according to the modified Hummers method. 3-mercaptopropyltriethoxysilane (MPTES) was used as a silane coupling agent. The products were characterized by a Fourier transform infrared spectroscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy and thermogravimetric analysis. The results confirmed the success of s-GO-MOR and showed excellent thermal stability.

Nafion-Silane Modified Mordenite Composite Membrane Synthesis and Characterization for Direct Ethanol Fuel Cell

Composite membranes, consist of Nafion and surface-modified mordenite as inorganic filler functioned as ethanol barrier, were prepared and used for direct ethanol fuel cell (DEFC). mordenite was modified using gamma-glycidoxypropyltrimethoxysilane (GMPTS) which has the epoxide group and 3-mercaptopropyl-trimethoxysilane (MPTS) which has the mercapto group as coupling agents on mordenite. The composite membranes were fabricated by adding 5 %weight modified mordenite into Nafion by solution casting and hot pressing with catalyst to produce MEA and tested in DEFC single cell stack. XRD, FT-IR, Mastersizer and SEM were used to study the morphology, physical and chemical properties of the filler and the composite membrane. The characterizations also included ethanol permeability and proton conductivity by using the diffusion cell and AC impedance test, respectively. The performance of the cell was evaluated in the DEFC under cell temperature from 30 to 70 °C and ethanol concentration of 1 M to 4 M. It was then compared to the recasted Nafion membrane.

Experimental Study on the Performance of DMFC Using Novel Composite Materials of Polypyrrole-Coated Polypropylene as BPs

Polypropylene/three-carbon-filler composite bipolar plates (BPs) of direct methanol fuel cell (DMFC) were fabricated by an injection molding. The composite materials were made of polypropylene (PP), carbon black, carbon fiber and graphite. Gas flow channel surfaces on the BPs were subsequently modified by polypyrrole (PPy) using a coating technique in order to improve surface electrical conductivity. This research is a feasibility study to use PPy-coated PP composite as BPs in a DMFC. The surface electrical resistance and performance in a fuel cell containing the composite BPs under DMFC operating conditions were evaluated against conventional graphite BPs. The surface resistance values of PPy-coated PP composites decreased around six orders of magnitude, compared with those values of PP composites. According to the performance results, PPy-coated composite BPs can be used in DMFC if the surface adhesion between a PPy layer and the BP surface was further improved.

One step NaBH 4 reduction of Pt-Ru-Ni catalysts on different types of carbon supports for direct ethanol fuel cells: Synthesis and characterization

Abstract The ternary catalyst Pt75Ru5Ni20 was conducted on various types of carbon supports including functionalized Vulcan XC-72R (f-CB), functionalized multi-walled carbon nanotubes (f-MWCNT), and mesoporous carbon (PC-Zn-succinic) by sodium borohydride chemical reduction method to improve the ethanol electrooxidation reaction (EOR) for direct ethanol fuel cell (DEFC). It was found that the particle size of the metals on f-MWCNT was 5.20 nm with good particle dispersion. The alloy formation of ternary catalyst was confirmed by XRD and more clearly described by SEM element mapping, which was relevant to the efficiency of the catalysts. Moreover, the mechanism of ethanol electrooxidation reaction based on the surface reaction was more understanding. The activity and stability for ethanol electrooxidation reaction (EOR) were investigated using cyclic voltammetry and chronoamperometry, respectively. The highest activity and stability for EOR were observed from Pt75Ru5Ni20/f-MWCNT due to a good metal-carbon interaction. Ru and Ni presented in Pt-Ru-Ni alloy improved the activity and stability of ternary catalysts for EOR. Moreover, the reduction of Pt content in ternary catalyst led to the catalyst cost deduction in DEFC.

Effect of Solution Casting Temperature on Characteristic of Nafion®-Mordenite Composite Membrane for Direct Methanol Fuel Cell

In this paper, proton conducting composite membranes of Nafion®-mordenite for direct methanol fuel cell (DMFC) were prepared using solution casting method. Mordenite, used as inorganic filler, was incorporated into Nafion polymer in order to improve membrane properties for DMFC application. Effect of solution casting temperature on resulting composite membranes was focused. The temperature of the membrane preparation was varied from 80 to 120°C. Properties and morphology of the resulting membranes including solubility, water uptake, ion – exchange capacity were investigated and reported. It was found that composite membrane prepared at 100°C gave the most alcohol resistance and mechanical stability membrane with 0.59% soluble. Furthermore, it gave highest ion – exchange capacity, 0.10 meq⋅g-1, which is 33% and 98% higher than the membranes prepared at 80°C and 120°C respectively.

Analytical Model for Effect of Polymer Composite Membrane Properties on Direct Methanol Fuel Cell Performance

Abstract. Performance of direct methanol fuel cell (DMFC), using polymer composite membrane, can be directly affected by membrane properties, including permeability, proton conductivity and membrane thickness. In order to obtain high DMFC performance, methanol permeability of the membrane should be low, while keeping high proton conductivity. This may be achieved by modification of incorporating inorganic filler into high proton conducting membrane. In this work, the analytical modeling for DMFC performance prediction was developed to be a guideline for Nafion based membrane improvement. Methanol permeability and proton conductivity were set at 0.30 – 5.60 cm2×S-1 and 0.08 – 0.15 S×cm-1 with the thickness of 25 – 1000 μm. The results show that DMFC performance strongly depends on the methanol permeability especially with thin membrane giving maximum power density of 1034 and 100mW×cm-2 at the permeability of 0.30 and 5.60 cm2×S-1, respectively, with thickness of 45 μm, while with thick membrane the permeability has negligibly effect. However, the proton conductivity mainly affects DMFC performance only with thick membrane as a result of ohmic resistance.