Environmental Association of Burning Agricultural Biomass in the Indus River Basin

Ferromagnetic Biochar Prepared from Hydrothermally Modified Calcined Mango Seeds for Fenton-like Degradation of Indigo Carmine

Biochar and ferromagnetic biochar obtained from the pyrolysis of dried mango seeds and modified using a hydrothermal method were used as catalyst for the heterogeneous degradation of indigo carmine in an aqueous medium. These prepared biochars were characterized using different techniques: Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). The analyses of the results revealed the presence of iron oxide in the form of magnetite (Fe3O4) in the catalyst. The catalytic tests carried out with this composite material showed a significant degradation of indigo carmine. The maximum degradation of indigo carmine in the aqueous solution was reached after 240 min of agitation. The Fenton degradation process using irradiation with a 100 W electric lamp and hydrogen peroxide (concentration 4 mol/L) showed the best results at pH = 3. From this study, it emerged that the second-order kinetic model better described the degradation process, and it gave lower half-lives compared to those obtained with the first-order kinetic law. The study also showed that ferromagnetic biochar could be prepared from mango seeds and used for the degradation of indigo carmine in an aqueous solution.

Analyzing asymmetric impact of economic growth, energy use, FDI inflows, and oil prices on CO2 emissions through NARDL approach

Even though numerous studies explore the impact of macroeconomic variables on carbon dioxide (CO2) emissions, only a few existing studies estimate the asymmetric impact and causality. By considering the significance of asymmetries, this study investigates the asymmetric impact of economic growth, energy use, and foreign direct investment inflows on CO2 emissions in India wherein oil prices are included as additional variable. The kinked exponential growth of these variables over the period 1986-2014 is also estimated. To this end, nonlinear autoregressive distributed lag (NARDL) model and asymmetric causality test are used. The results show that increase in economic growth would decrease CO2 emissions, while a reduction in economic growth would increase CO2 emissions which implies an inverted U-shaped link between economic growth and CO2 emissions. The positive and negative shocks in oil prices have a favorable and significant impact on CO2 emissions as well. Furthermore, the energy consumption with positive shock shows a positive and significant impact on CO2 emission. Besides, the findings of foreign direct investment inflows support the pollution heaven hypothesis. In light of these results, this study also suggested some policy implications and future research avenues in the concluding section.