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Electrochemical methanol reformation (ECMR) is an alternative promising technology for producing hydrogen at low energy consumption compared to water electrolysis. In this process, solid polymer electrolyte Nafion® is widely employed, due to its superior proton conductivity. However, major limitations are the utilisation of expensive platinum based catalysts, high cost of the above membrane and the crossover of methanol through the polymer electrolyte membrane. In the present work, attempt has been to made to use low cost polymer electrolyte membrane and less noble electro catalyst. A series of Anion Exchange Membranes (AEM) are synthesized from Poly (2, 6-dimethyl-1, 4-phenylene oxide) (PPO) for its application in ECMR. PPO is successfully made into anion conducting by chloromethylation followed by quaternization. Two AEM's are synthesized by optimizing chloromethylation reaction time to 5 h and quaternization time to 5 and 8 h and are labelled as QPPO (C5, Q5) and QPPO (C5, Q8) respectively. Further, with the view to improve the anion conductivity further, composite AEMs are prepared by incorporating inorganic anion conducting quaternized graphene oxide particles in the matrix of PPO and QPPO (C5, Q8) polymers separately to obtain two polymers PPO/QGO and QPPO/QGO. The anionic conductivity of PPO/QGO and QPPO/QGO polymer is 1.2 × 10−4 and 1.5 × 10−4 S cm−1 respectively. Both the membranes are subjected as electrolyte for ECMR application using membrane electrode assembly made by with in house synthesized nitrogen doped graphene supported Pd catalyst (Pd/NG) as anode catalyst and commercial Pt/C as cathode catalyst. The performance of composite membrane was compared with the commercial Fumasep® FAA anion exchange membrane. The polarization studies of ECMR cell with composite membrane shows comparable performance with that of commercial Fumasep® FAA-2 FAA membrane. The durability of the membrane(s) in the electrolysis environment was tested for about 20 h.

Organic solvents like methanol is commonly used in pharmaceutical industries as a separation media in the purification process of drugs, and it contains various contaminants like ethyl acetate, methyl formate, acetic acid, etc. in the effluent stream. In the aspect of utilizing this industrial waste/effluent, we attempted to generate pure hydrogen by Proton Exchange Membrane (PEM) based Electrochemical Methanol Reformation (ECMR) process. The present study reports, the influence of ethyl acetate as a potential impurity in methanol on performance of ECMR cell for hydrogen production. Initially, electrochemical half-cell studies carried out using various concentrations of ethyl acetate (0.25, 0.5 and 1%) and their effect was studied systematically. In addition, the ECMR full cell performance was also evaluated with these concentrations and performance deterioration observed during long operation hours and discussed the possible regeneration method in view of its further practical development. The observed cell performance deterioration was attributed to formation of reaction intermediates during oxidation of methanol-water, which was identified by using FTIR and NMR analysis. Potentiostatic mode with operating potential of ∼0.86 V was used as a method to regenerate the cell performance.

The expanded polytetrafluoroethylene (ePTFE) substrate based composite polymer electrolyte membrane was prepared using Nafion® ionomer and titania nanotube (TNT) as a filler in the matrix and demonstrated its use as electrolyte in a polymer electrolyte Membrane (PEM) based electrochemical methanol reformation (ECMR) for hydrogen generation. The composite membranes were characterised for their mechanical strength and thermal stability using dynamic mechanical analyser (DMA) and thermo–gravimetric analysis (TGA). Methanol cross-over studies were carried out for composite membrane and compared with commercial Nafion® 117 membrane. The PEM based ECMR cell with composite membrane shows comparable performance related to Nafion® 117 with lower methanol crossover rates.

Simultaneous detection of 1,4-, 1,2- and 1,3-dihydroxy benzene (DHB) isomers on a glassy carbon electrode modified with graphitized mesoporous carbon (GCE/GMC) in pH 7 phosphate buffer solution was demonstrated. GCE/GMC showed absence of any strong adsorption of the DHB isomers on the working electrode surface. The electrochemical response of 1,4-DHB resembled that of 1,2,3-trihydroxybenzene (gallo group) on the GCE/GMC. Differential pulse voltammetry was used as a tool for quantification of the DHB isomers. Constructed calibration plots were linear in the window 4 × 10−5 to 2.5 × 10−4, 2.5 × 10−5 to 2.0 × 10−4 and 2.5 × 10−5 to 2.0 × 10−4 mol L−1 for the 1,4-, 1,2- and 1,3-DHB, respectively. Corresponding detection limits (S/N = 3) were 0.91, 1.31 and 0.67 μM. Polyphenols extracted from three different tea samples using hot water were successfully analyzed with recovery values ∼100%.