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In the present study, low cost platinum based bimetallic electrocatalyst Pt‐Ni/CAB with varying Pt to Ni atomic ratios 3:1, 1:1, and 1:3 were successfully synthesized for oxygen reduction reaction (ORR) of the developed proton exchange membrane fuel cell (PEMFC). The solvothermal process was adopted for the synthesis of Pt‐Ni(3:1)/CAB, Pt‐Ni(1:1)/CAB, and Pt‐Ni(1:3)/CAB using dimethyl sulfoxide (DMSO) as solvent at a temperature of 190°C which is very close to the boiling point. The Pt‐Ni/CAB exhibited the highest activity for the ORR in half‐cell and single cell PEMFC performance. The electrocatalysts Pt‐Ni(1:3)/CAB appeared with smallest crystalline FCC structures having crystallite size of 8.33 nm. The transmission electron microscopy (TEM) analysis also show that the Pt‐Ni(1:3)/CAB has smallest particle size of 1.67 ± 0.45 nm. The cyclic voltammetry (CV) analysis shows Pt‐Ni(1:3)/CAB electrocatalyst offers less activation loss at ORR peak at a potential of 0.16 V as compared to Pt‐Ni(3:1)/CAB (ORR peak – 0.12) and Pt‐Ni(1:1)/CAB (ORR peak – 0.11). The synthesized Pt‐Ni(1:3)/CAB produced a maximum power density of 18.86 mW/cm2 at a maximum current density of 44.8 mA/cm2 with an open‐circuit voltage of 0.914 V at a room temperature of 33°C. The power density improved around 1.34 times when the cell temperature was raised from 33 to 70°C. The Pt‐Ni(1:3)/CAB cathode electrocatalyst could be used as economical to substitute costly commercial pure platinum based electrocatalyst. [ABSTRACT FROM AUTHOR]

Hydrogen gas of ultrapure form has been produced via electrochemical splitting of water molecules using an efficient water electrolysis method. The IrO2 based low-cost composite anode has been developed in the laboratory to split water molecules via electrolysis with the cathode electrocatalyst as Pt (40 % by wt.)/CHSA. The electrocatalysts loading at anode and cathode are 1 mg/cm² at both electrodes. Other components of the manufactured electrodes are Nafion® (5 wt%) ionomer dispersion, PTFE, and isopropyl alcohol. The electrolyzer is fabricated using a perspex sheet i.e., polymethyl methacrylate. The rate of hydrogen production is measured for different applied currents, voltage, and concentrations of H2SO4 electrolyte in the electrolysis mode at a temperature of 20 °C. The IrO2 composites anode used as oxygen evolution reaction are studied by electrochemical impedance studies (EIS) and cyclic voltammetry to evaluate the electrocatalytic activity and charge transfer resistance of the developed composite anode. The IrO2 anode electrode exhibits a higher HER activity concentration of 0.75 M H2SO4 electrolyte than that of the 0.25 M and 0.50 M H2SO4 electrolyte concentration as is shown by EIS. The highest hydrogen production rate of 0.9 mL/min is obtained at the voltage of 1.9 V and applied current of 0.1 A using the electrolyte concentration of 0.75 M H2SO4. However, the hydrogen production rate is very low (0.33 mL/min.) when a low voltage of 1.6 V and current of 0.04 A was applied at the same concentration of electrolyte (0.75 M) H2SO4. IrO2 is known to be one of the most active electrocatalysts for the oxygen evolution reaction in a liquid electrolyte, exhibiting high electronic conductivity and stability in the electrochemical system. [ABSTRACT FROM AUTHOR]

In the present research work, multiphase catalytic pyrolysis (in-situ catalytic cracking) of waste expanded polystyrene (WEPS) has been carried out using calcium carbonate (CaCO3) as a solid base catalyst. The multiphase catalytic pyrolysis of WEPS has been conducted at different temperatures ranging from 400°C to 700°C at a heating rate of 15 °C/min and feed to catalyst ratio of 20:1. The thermal pyrolysis of WEPS has produced a maximum liquid yield of 94.37 wt.% at a reaction temperature of 650oC and heating rate of 15 °C/min. Whereas, the maximum liquid yield of 85.99 wt.% is obtained at a reaction temperature of 550°C and heating rate of 15 °C/min for the multiphase catalytic pyrolysis. The GC-FID analysis confirm that the thermal pyrolysis oil is mainly composed of benzene (0.62 wt.%), toluene (10.21 wt.%), ethylbenzene (0.55 wt.%) and styrene (84.74 wt.%). Whereas, the pyrolysis oil obtained from multiphase catalytic pyrolysis using CaCO3 catalyst contains very high styrene content of 93.24 wt.% along with a very low amount of fuel range hydrocarbons benzene (0.25 wt.%), toluene (2.09 wt.%) and ethyl benzene (0.52 wt.%). Thus, the present study clearly indicates that the basic catalyst CaCO3 shows the high selectivity towards the styrene monomer. [ABSTRACT FROM AUTHOR]

Highly efficient and low‐cost Pt‐Co/CAB bimetallic cathode electrocatalysts were synthesized for hydrogen‐based proton exchange membrane fuel cell (PEMFC) using three different types of solvent, namely, dimethyl sulphoxide (DMSO), dimethylformamide (DMF), and ethylene glycol (EG). The physical characterization of synthesized cathode electrocatalysts Pt‐Co/CAB‐DMSO, Pt‐Co/CAB‐DMF and Pt‐Co/CAB‐EG was performed by scanning electron microscope–energy‐dispersive X‐ray (SEM–EDX), X‐ray diffraction (XRD), and transmission electron microscopy (TEM) techniques, whereas the electrochemical investigation of all three Pt‐Co/CAB electrocatalysts was performed by CV and EIS studies. The synthesized Pt‐Co/C‐EG electrocatalyst produced the highest power density of 19.61 mW/cm2 at a room temperature of 33°C. The power density increased to 26.11 mW/cm2, that is, 133%, when the cell operating temperature was raised from 33 to 70°C. The excellent performance of the Pt‐Co/CAB‐EG cathode electrode proves that it can be recommended as a commercial electrocatalyst for PEMFC cathode. In addition, the EG/EG was identified as the best solvent for the synthesis of Pt‐Co/CAB cathode electrocatalysts. [ABSTRACT FROM AUTHOR]

In this work, thermal and catalytic pyrolysis of waste expanded polystyrene (WEPS) have been investigated in a laboratory designed semi-batch reactor in the temperature range of 400-700° and heating rate of 15 °/min to produce gasoline range lower paraffins and valuable aromatics i.e., benzene, toluene and ethylbenzene (BTE). Three different type of reactor arrangements i.e., liquid phase/A-type, vapour phase/B-type and multiphase/AB-type have been used to conduct the catalytic pyrolysis of WEPS using nickel on silica-alumina catalyst. The thermal pyrolysis of WEPS produced highest liquid yield of 94.37 wt.% at a temperature of 650? and heating rate of 15 ?/min, whereas, liquid phase/A-type, vapour phase/Btype and multiphase/AB-type catalytic pyrolysis produced highest liquid yield of 88.54 wt.%, 83.21 wt.%, and 81.15 wt.%, respectively, at the same heating rate of 15 oC/min and at the temperature of 600?, 550?, and 550?, respectively. The pyrolysis oil obtained from thermal pyrolysis mainly contains styrene monomer of 84.74 wt.% and very less BTE content of 11.38 wt.%. Among, the all types of catalytic pyrolysis, AB-type/multiphase pyrolysis produced pyrolysis oil with highest amount of BTE content of 28.56 wt.%. Furthermore, the pyrolysis oil obtained from A-type, B-type and AB-type catalytic pyrolysis contains low styrene content of 69.94 wt.%, 65.67 wt.% and 55.55 wt.%, respectively, as compared to thermal pyrolysis (84.74 wt.%). [ABSTRACT FROM AUTHOR]

In the present work, glycerol‐based air breathing microfluidic fuel cell (μFC) is investigated. The noble metal Pd and non‐noble metal Ni‐based bimetallic synthesized electrocatalyst (Pd‐Ni/C) were used for glycerol electrooxidation and commercial Pt/CHSA was used as cathode electrocatalyst. The anolyte is glycerol mixed with KOH electrolyte. The atmospheric air and calcium hypochlorite mixture are used as oxidant in cathode and catholyte, respectively. Acetylene black carbon is used as electrocatalyst support with low metal loading of 20 wt% Pd and Ni at their different weight ratios (Pd/Ni) of 16:4, 10:10, and 4:16 to synthesize bimetallic Pd‐Ni/C anode electrocatalysts. The crystal structure of the synthesized electrocatalyst was determined by X‐ray diffraction (XRD) analysis. The surface morphology and surface concentration of synthesized electrocatalyst were determined by scanning electron microscopy (SEM) and energy dispersive X‐ray spectroscopy (EDX), respectively. The particle size of synthesized electrocatalyst was determined by transmission electron microscopy (TEM) analysis. The electrochemical activity of Pd‐Ni/C was investigated by cyclic voltammetry analysis. The electrocatalyst Pd‐Ni (10:10)/C gives higher electrocatalytic activity for glycerol electrooxidation compared to other ratios of electrocatalyst. A single air breathing μFC is investigated using various key parameters where air alone as oxidant gives open circuit voltage (OCV) of 0.42 V and maximum power density of 1.27 mW/cm2. While using calcium hypochlorite and air as mixed oxidant, the OCV was increased to 0.72 V and maximum power density increased to 3.43 mW/cm2, which are 1.71 and 2.7 times, respectively, more than that of air as oxidant only. [ABSTRACT FROM AUTHOR]

The plastic waste poly styrene (PS) has been selected for the conversion to value added useful products using pyrolysis. The thermal and catalytic pyrolysis of polystyrene (PS) are investigated at reaction temperature ranging from 500°C to 800°C for 30 min, as an effective way to recycle polystyrene and produce valuable aromatic hydrocarbons benzene, toluene, ethyl benzene and xylene (BTEX). The catalytic pyrolysis is performed using commercial catalyst ZSM-5 which is reused repeatedly twice and further regenerated to evaluate the stability of ZSM-5 for PS pyrolysis with reference to BTEX formation. The maximum liquid yield of 96 wt. % and 86.2 wt. % are obtained at a temperature of 700°C for thermal pyrolysis and catalytic pyrolysis (fresh catalyst/1st run), respectively. The product analyses show that liquid yield contains substantial amount of BTEX with the increase in temperature for fresh ZSM-5. The BTEX yield is significantly increased for catalytic pyrolysis (fresh catalyst/1st run) i.e., about 75 wt. % for fresh ZSM-5 in comparison to thermal pyrolysis at a temperature of 700°C. There is very minute change in BTEX yield for the 2nd and 3rd run of catalytic pyrolysis using spent catalyst ZSM-5. The maximum aromatic (BTEX) of 23.71 wt. % for fresh ZSM-5 is obtained at the temperature of 700°C. However, spent ZSM-5(3rd run) produced 20.45 wt. % BTEX at the same temperature. The regenerated ZSM-5 produced only 2 wt. % less BTEX yield in comparison to fresh ZSM-5 at the optimum temperature of 700°C. The gas chromatography and other fuel test have been performed for liquid yield characterisation. The characteristics of product prove that the liquid hydrocarbon has potential to use it as fuel. [ABSTRACT FROM AUTHOR]

Waste polypropylene has been subjected to pyrolysis followed by in-situ aromatization in a specially designed semi batch reactor at the temperature ranging from 500 - 800°C. The molecules of interest are valuable aromatics benzene, toluene, ethyl benzene and xylene (BTEX) which appeared highest amount in the liquid mixture. The catalyst used is commercial ZSM-5 (30:1). The catalytic pyrolysis of PP is studied in a semi batch reactor in two different phases, keeping the catalyst in the liquid phase (L-type) and liquid and vapor phase/multiphase (M-type), respectively. The BTEX yield is enhanced significantly using multiphase catalytic pyrolysis of polypropylene. The catalytic performance of ZSM-5 catalyst for PP pyrolysis is evaluated with respect to target aromatics BTEX. The thermal pyrolysis of PP produced maximum liquid yield of 80.56 wt. % at a temperature of 700°C. The commercial catalysts ZSM-5 produced highest liquid yield of 86.3 wt. % for liquid phase (L-type) pyrolysis. The BTEX yield is significantly increased from 30.9 wt.% for thermal pyrolysis to 53.09 wt. % for catalytic multiphase/M-type pyrolysis. Almost 72% increase in BTEX yield is recorded for catalytic multiphase/M-type pyrolysis in comparison to thermal process. The pyrolysis oil is analyzed using GC-FID, carbon residue test and other fuel testing methods to examine the suitability of its end use and aromatic content. [ABSTRACT FROM AUTHOR]

Ethanol electrooxidation was thoroughly investigated on laboratory synthesized Pt-Ru nano electrocatalysts. Low cost acetylene black carbon functionalized by HNO3 was used as support material for synthesized Pt-Ru/CAB: electrocatalysts. The effect of synthesis methods on the major electrocatalytic properties of Pt-Ru/CAB electrocatalysts were studied thoroughly. The electrocatalysts Pt-Ru/CAB were manufactured by different chemical reduction methods. The electrocatalysts were designated as Pt-Ru/CAB-PLM for polyol reduction and Pt-Ru/CAB-FAM for formic acid reduction method, respectively. The electrocatalyst synthesis method and treatment of support material remarkably enhanced the catalytic performance of synthesized Pt-Ru/CAB electrocatalysts. The commercial Pt-Ru/C was selected as anode electrocatalyst for comparative study with the synthesis electrocatalyst in terms of performance in half cell study and in a single direct ethanol fuel cell as well. In the direct ethanol fuel cell, synthesized Pt-Ru/CAB-PLM produced maximum open circuit voltage of 0.71 V and highest power density of 6.02 mW/cm2 at a current density of 19.52 mA/cm2 at the room temperature of 35 °C. Whereas, the maximum power density of 5.13 mW/cm2 at a current density of 18.70 mA/cm2 and open circuit voltage of 0.717 V were obtained for commercial Pt-Ru/C electrocatalyst at the same temperature (35 °C). The power density enhanced around 2.17 times when cell temperature was increased from 35 °C to 80 °C using anode electrocatalyst Pt-Ru/CAB-PLM. The performance of synthesized Pt-Ru/CAB-PLM is excellent for the ethanol electrooxidation and, thus, could replace commercial Pt-Ru/C. [ABSTRACT FROM AUTHOR]

The electrooxidation study of methanol was performed at room temperature of 34 °C in a membraneless air breathing microfluidic fuel cell using laboratory made carbon cloth/gas diffusion layer (GDL). The anode and cathode electrocatalysts were Pt Ru (30%:15% by wt.)/High Surface Area Carbon (C HSA ) (Alfa Aesar, USA) and Pt (40% by wt.)/C HSA (Alfa Aesar, USA) respectively. The electrocatalyst loading at anode and cathode were similar, in the order of 1 mg/cm 2 . The oxidants at cathode were atmospheric oxygen or H 2 O 2 combined with atmospheric oxygen (air). The cell voltage and current density were measured for different concentration of fuel (methanol), oxidant (H 2 O 2 ) and electrolyte (KOH), respectively. The maximum open circuit voltage (OCV) of 0.47 V and power density of 0.97 mW/cm 2 at a current density of 6.9 mA/cm 2 were obtained for the fuel of 0.5 M methanol mixed with 1 M KOH and atmospheric fresh air as oxidant with 1 M KOH at cathode. Whereas, the maximum OCV of 0.68 V and power density of 3.8 mW/cm 2 at a current density of 18.75 mA/cm 2 were for methanol as fuel of 1 M mixed with 1 M KOH as electrolyte and 2 M H 2 O 2 as oxidant at cathode mixed with 1 M KOH as electrolyte in the presence of continuous diffusion of atmospheric fresh air. [ABSTRACT FROM AUTHOR]