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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…

We saw (Section 4.4) that CO₂ (carbon dioxide) reacts with quicklime (calcium oxide) in water at 25°C, under 1 atm generating calcium carbonate or limestone (CaCO₃). The process is a sequence of two reactions (4.14) and (6.1):

Today, fossil carbon provides us with fuels (energy), polymers (packaging, insulating and building materials, household utensils, glues, coatings, textiles, 3D-printing inks, furnitures, vehicle parts, toys, electronic and medical devices, etc.) and biologically active substances (drugs (Chapter 9), flavorings, fragrances, food additives, plant protection products, etc.). In this chapter we discover the modern materials of our civilization which are very often polymers derived from oil. They are referred to as “plastics” (annual world production: 380 × 10⁶ tons). Their production consumes 8% of the crude oil extracted (ca. 5 billion tons per year). An increasing part of the plastics originates from renewable resources (less than 10% today, see Section 11.10, bio-sourced plastics). Plastics make life easy for us, but at the underestimated cost of damage to our environment (Figure 8.1) and our health. They contaminate the hydrosphere and the agricultural soil. The atmosphere is also contaminated by microplastics…

Syngas is a mixture of carbon monoxide (CO) and molecular hydrogen (H₂) that can be converted into a host of industrial feedstocks including fuels such as gasoline, fuel oil and kerosene. We examine what are the most abundant sources of these two gases and describe some important transformations that continue to fascinate scientists because, with a reactant as simple as CO, which contains only one carbon atom, catalysts allow to condense it with H₂ and to form C–C bonds even though all oligomers of the (CO)_n type (n = 2, 3, …) are kinetically and thermodynamically unstable. Let us recall here that thanks to photosynthesis, Nature builds C–C bonds (e.g. D-glucose) from CO₂ and H₂O and solar light! (Section 1.4.2, reaction (1.8), Figure 1.10)…

The catalytic functionalization of C–H, C–OH and C–C bonds belongs to the most important processes in nature and the industry. In nature, this process occurs via involvement of enzymes, effectively and selectively, usually with very high turnover numbers. The pivotal role in enzymatic activity is played by the metal center cofactors, which involve several bioavailable transition metals, such as, iron, copper, manganese and zinc. In the industry, bond functionalization requires the presence of metal catalysts; therefore, a bio-inspired design of metal catalysts is a challenging approach. The recent advances in the catalysis of industrially important reactions, namely the oxidation and hydrocarboxylation of alkanes, the oxidation of alcohols and C–C coupling are reported. Convenient, environmentally friendly methods are presented, and the role and efficacy of the various transition-metal (iron, copper, zinc, manganese, nickel, vanadium, palladium and cobalt) catalysts are explored.

The potential applications for heterogeneous catalysts (supported metallic complexes, metal–organic frameworks (MOFs) or polynuclear complexes) in C–H and C–OH activation are tantalizing. In response to the opportunity, novel strategies have been recently developed, which present a critical step toward harnessing the experimental factors, such as yield and selectivity, by enabling new techniques and hence real-world applications. This chapter provides an up-to-date survey (from the past five years) of the most promising novel routes by summarizing the progress made in the use of unconventional activation methods for performing oxidation reactions, highlighting the synergy of these technologies with heterogeneous catalysis. Focus is centered on both usual catalysts activation methods and less usual ones, such as ultrasounds, microwaves, grinding (mechanochemistry), as well as their combined use.