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In this study, electrochemical oxidation of petroleum was performed for the first time. Since petroleum is a rich source of hydrocarbons, its oxidation and electron production resulting in the production of electricity which is green energy is much more efficient than burning it. Electrochemical oxidation of petroleum with Ni-porphyrin-modified graphite electrode in alkaline media and by cyclic voltammetry (CV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS) techniques were investigated. Due to the existence of two aqueous and organic phases, adsorption played a vital role in the process. To further confirm the accuracy of petroleum electrooxidation, electrooxidation of its compounds such as xylene and toluene was performed with the Ni-porphyrin electrode and by the mentioned techniques, which confirmed the previous data.

In this work, a simple method is reported for the synthesis of bundles of carbon nanostructures under room temperature and atmospheric pressure. A pulsed Nd:YAG laser (355 nm, 10 Hz) is focused into the mixture of ferrocene and xylene solutions to produce the nanostructures in which ferrocene plays the role of a catalyst while xylene is the carbon source for nanostructure growth. During the period of irradiation, the color of solution turns into dark brown from transparent orange. Upon the completion of irradiation, typically for an hour, a variety of bundles of carbon nanostructures are found in the solution. Raman spectroscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) are used to investigate the nanostructures.

Fe₂(MoO₄)₃ nanoplates were prepared via a simple hydrothermal process. The average crystalline size of these nanoplates is 85.8nm. The sensor based on Fe₂(MoO₄)₃ shows a high gas sensing performance to xylene. The response of Fe₂(MoO₄)₃ sensor is 25.9–100ppm xylene at optimum operating temperature of 340${}^{\circ }$C. The response and recovery times to 100ppm xylene are 4 and 10s, respectively. Furthermore, the Fe₂(MoO₄)₃ sensor exhibits remarkable selectivity detection of xylene gas with negligible responses to toluene and benzene. Therefore, the Fe₂(MoO₄)₃ is a promising material for the detection of xylene gas sensors.

Some people think that carbon and sustainable development are not compatible. This textbook shows that carbon dioxide (CO₂) from the air and bio-carbon from biomass are our best allies in the energy transition, towards greater sustainability. We pose the problem of the decarbonation (or decarbonization) of our economy by looking at ways to reduce our dependence on fossil carbon (coal, petroleum, natural gas, bitumen, carbonaceous shales, lignite, peat). The urgent goal is to curb the exponential increase in the concentration of carbon dioxide in the atmosphere and hydrosphere (Figures 1.1 and 1.2) that is directly related to our consumption of fossil carbon for our energy and materials The goal of the Paris agreement (United Nations COP 21, Dec. 12, 2015) of limiting the temperature increase to 1.5 degrees (compared to the pre-industrial era, before 1800) is becoming increasingly unattainable (Intergovermental Panel on Climate Change (IPCC), report of Aug. 6, 2021). On Aug. 9, 2021 Boris Johnson, prime minister of the United Kingdom, declared that coal needs to be consigned to history to limit global warming. CO₂ has an important social cost…

This chapter aims to illustrate the research that was conducted in Portugal or in collaboration with Portuguese research groups in the 2011–2022 period on the oxidative conversion of volatile organic compounds (VOCs) to useful building blocks. It concerns the selective oxidation under mild catalytic oxidations of some VOCs (toluene, xylene, ethylbenzene, styrene and n-hexane), which are hazardous to human health and the environment. Both homogeneous and heterogeneous catalysts are discussed.