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The present investigation demonstrates the conversion of n-butanol to aromatics (BTA) including building block aromatics in one step over Ga modified HZSM5 catalysts in a fixed bed reactor under varying process parameters (temperature, pressure, and weight hourly space velocity, WHSV). The several Ga modified HZSM5 catalysts prepared by the incipient wetness impregnation method were well characterized by several techniques. The different gallium species (GaO+ and Ga+ species) formed on Ga-HZSM5 catalysts, as confirmed by the characterization results, behave as Lewis acid sites, which played a crucial role in the enhancement of the dehydrogenation reaction and suppression of the hydride transfer reaction leading to the production of different aromatics. Specifically, the selectivity to benzene, toluene, ethylbenzene, and xylenes (BTEX) was enhanced on deposition of Ga on the HZSM5 catalyst. The selectivity to different aromatics was also affected by the variation of different process parameters. The total aromatics selectivity was raised with increasing temperature and decreasing WHSV. However, the aromatics production was reduced at high operating pressure. The high operating pressure led to the production of higher aromatics and deposition of these aromatics caused the deactivation of the catalyst. Characterization of spent catalysts confirmed the deposition of polynuclear aromatics as hard coke. The maximum total aromatics selectivity of 76.0% (BTEX 69.2%) was achieved for the 5Ga-HZSM5 catalyst at 823 K, 0.75 h−1 WHSV, and 1 atm. A comprehensive reaction pathway was recommended considering the product distribution obtained under the studied reaction conditions. © 2022 The Royal Society of Chemistry

The demand for energy storage supercapacitor devices has increased interest in completing all innovative technologies and renewable energy requirements. Here, we report a simple method of two polyoxomolybdate (H4[PVMo11O40] and H5[PV2Mo10O40]) doped polyindole (PIn) composites for electrochemical supercapacitors. The interactions between polyoxomolybdates and PIn were measured by Fourier transform infrared spectroscopy (FTIR), and powder XRD, and stability was measured by thermogravimetry. The field emission scanning microscopy (FESEM) was employed to investigate the morphology of the materials. The electrochemical measurements show that the PIn/PV2Mo10 electrode exhibits a higher capacitance of 198.09 F/g with an energy density of 10.19 Wh/kg and a power density of 198.54 W/kg at 0.2 A/g current density than the PIn/PVMo11 electrode. Both electrodes show a pseudocapacitance behavior due to the doping of redox-active polyoxomolybdates on the PIn surface and enhance the electrochemical properties. The electrodes' capacitive nature was measured by electrochemical impedance spectroscopy (EIS), which shows that the PIn/PVMo11 electrode has a resistive nature within the electrode-electrode interface. Moreover, the PIn/PV2Mo10 electrode offers remarkable cycle stability, retaining ∼84% of its capacitance after 10,000 cycles (∼83% for the PIn/PVMo11 electrode). The higher specific capacitance, faster charge/discharge rates, and higher cycle stability make them promising electrodes in supercapacitors.