There exist sustainable alternatives for replacing oil, gas or coal as energy sources. However, replacing oil, gas or coal as feedstocks for basic chemicals, polymers or fine chemicals is much more difficult. In addition to the utilization of carbon dioxide, only recycling and biomass remain to meet all non-fossil demand in the future. In doing so, we encounter two problems: the low efficiency of photosynthesis from an industrial point of view (plants 1 percent, algae 6 percent) and the decrease of globally per capita available agricultural land. Moreover, living organisms and their enzymes are more suitable for the synthesis of complex and high-quality molecules but less for commodity chemicals. Time is pressing to take the right measures for rapid defossilization and efficient resource use. The best possible action plan for such a complex challenge can only be formulated together with all partners involved such as oil-, petrochemical-, biotech- and agricultural-companies and others.

What does defossilization mean? Defossilization (or defossilation) means replacing fossil carbon sources with alternatives, or at least reducing the demand. This can be done through the circular economy, carbon dioxide as a raw material and carbon from biomass. For the future of humanity, sustainability is essential in all areas, and defossilization or abandonment of oil, gas and coal, especially as energy source is urgent. Yet this task is gigantic. In 1859, the first commercial oil drilling was carried out in Pennsylvania (USA). Today, we consume around 90 million barrels of oil worldwide, and Switzerland imported around 22,000 tons of crude oil and crude oil products in 2021 – per day!

Defossilization in a short time will be difficult. Unfortunately, the replacement of oil, gas and coal with biogenic energy and raw material sources is an almost unsolvable challenge with a growing population and dwindling agricultural land. As of today, about 0.18 hectares of agricultural land per capita are available to humans worldwide. 50 years ago, it was over 0.28 hectares. As a result, the oil and petrochemical industry remains systemically relevant.

Demand for oil is falling. Oil demand peaked in 2019 at about 100 million barrels per day. Which is actually good news, but also carries risks. Because of the dwindling agricultural land (absolute and per capita), we will be dependent on fossil raw materials for a long time to come. Although the demand for fossil raw materials in the chemical sector has been increasing in relative and absolute terms for years, investments in industry have been scaled back in the last ten years. This carries the risk that defossilization, especially during a transition phase, will be accompanied by disorderly adjustments and supply bottlenecks.

Defossilization in the energy sector is easier. For oil, gas or coal as energy sources, there are many non-biogenic and sustainable alternatives available today, such as photovoltaics, wind and geothermal energy, and possibly also new nuclear reactor concepts. It is also possible to produce biofuels using a variety of processes, but only for selected niche markets such as aviation fuels.

Defossilization outside the energy sector. The chemical industry is responsible for 14 percent of global oil and 8 percent of natural gas consumption worldwide, as 90 percent of chemicals are made from oil and gas. The rest comes from coal and biomass. The range of chemical products produced ranges from primary chemicals with huge volumes such as ethylene, propylene, ammonium and methanol) to plastics and the most complex organic molecules with dozens of chiral centers, some of which are produced in very small quantities.

Crude oil will soon be used primarily for plastic? About a hundred years after Edwin L. Drake began commercial drilling in Pennsylvania, industrial production of plastics began. Their demand has grown faster than for any other product and has almost doubled since the turn of the millennium to over three billion barrels (1 barrel = 159 liters) per year. Plastics are a major driver of petrochemical demand, and by 2050, oil demand related to plastic consumption could exceed that of road passenger transport.

What does the chemical industry need? There are about 900 Swiss chemical companies, most of which are SMEs active in the sale and distribution of chemicals. Only a small proportion develops and produces products. But all manufacturing chemical companies in Switzerland face similar challenges and are increasingly facing fierce international competition.

Options of the chemical industry. The main options available for more sustainable processes and defossilization are: 

• Innovation and more efficient synthesis processes

• Reduction of energy and raw material consumption

• Renewable raw materials

• CO2 as a raw material and carbon source

Innovation is key. The innovation and development of new technologies is essential for defossilization. Also for organic chemistry, which has become an indispensable industrial activity since its beginnings 200 years ago. Today, the organic chemical toolbox allows the synthesis of the most complex structures. However, with a huge disadvantage: the more complex the structures, the greater the Process Mass Intensity (PMI) and E-factor (E = waste produced/product produced). In extreme cases, the latter can be a thousand or even higher: This means that around one ton of waste and by-products are produced per kilogram of product.

Biotechnology for greater efficiency. Living organisms and their enzymes, on the other hand, are predestined for the synthesis of the most complex and high-quality molecules. New processes have to access biosynthesis, biocatalysis and biotransformation, since complex and high-quality molecules can almost always be produced many times more efficiently biotechnologically. The implementation of biotechnological methods must therefore be driven forward much faster.

Halogenation as an example About 20 percent of pharmaceutical (small) molecules and 30 percent of agrochemical products are halogenated (F, Cl, Br, I). Although chemical halogenation is a well-established technology, hazardous or toxic chemicals are used, and the atomic economy and specificity are low. The pharmaceutical and agrochemical industries therefore have a common interest in developing more sustainable halogenation chemistry by replacing chemical halogenation methods with biotechnological solutions.

Reduction of raw material consumption and energy consumption. The potential of reduction of raw material consumption has probably been exhausted in the chemical industry, as processes have been continuously optimized. The industry has been applying its own guidelines for sustainable practices for quite some time, such as Twelve Principles of Green Chemistry and Responsible Care.

Reduction of energy consumption. On the other hand, there is a need for adaptation of energy supply. While Switzerland's primary energy consumption is decreasing for various reasons and despite an increasing population, future electricity demand is expected to increase (e-mobility, heating, cooling, increasing digitalization, etc.).

Use of sunlight. 0.017 percent of the amount of energy supplied by the sun per year would cover the global energy demand of 944,444,400 terawatt hours. Professor Greta Patzke from the University of Zurich and SATW member would therefore like to chemically store solar energy and use artificial photosynthesis to break down water into hydrogen and oxygen.

Hydrogen as a key point. Hydrogen plays a key role. However, the hydrolysis of water into hydrogen requires efficient solutions for sustainable electricity. Here, CSEM and EPFL are developing new tandem cells made of silicon and a perovskite layer with an efficiency of 31.25 percent. By comparison, the world record for silicon solar cells is currently 26.8 percent (theoretically possible: 29.4 percent).

Biomass, a sought-after raw material. The only significant usable biomass source that does not affect food and feed production is wood. However, economically viable value chains of a wood-based bioeconomy accessible to Switzerland are limited to conventional wood use, which is why Swiss wood is hardly an option as a raw material base for chemicals or biofuels.

CO2 as a raw material. With almost 100 kilograms of hydrogen per cubic meter, methanol is the best hydrogen storage medium. It is also an important C1 building block for basic chemicals (e.g. formaldehyde, ethylene, propylene) and, with an annual production of 100 million tons after crude oil, also the world's most traded liquid. Methanol is also one of the most suitable candidates for sustainable defossilization without side effects, as the carbon dioxide can be taken from the atmosphere and converted into methanol and other products. Switzerland can also contribute to this path with innovative solutions.

Production of methanol from carbon dioxide. The group led by Professor Javier Pérez-Ramírez from the ETH Zurich developed a new catalyst (Pd-In2O3/ZrO2) for the conversion of carbon dioxide (CO2) and hydrogen (H2) to methanol (CH3OH). Silent Power AG, based in Cham, plans to produce methanol fuel locally from H2O and sustainable electricity with the Econimo mini power plant, among other things. Another Swiss company, Climeworks, was founded as an ETH spin-off in 2009 to extract CO2 from the ambient air. The CO2 can be stored in basaltic rock layers (Air Capture and Storage, DAC+S) or possibly reused directly as raw material.

Defossilization without side effects. In Switzerland, we actually have the best conditions for a smooth defossilization. Switzerland's largest companies are commodity traders – with Geneva-based oil trader Vitol at the helm. Chemistry and biotechnology are by far Switzerland's largest export contributors, and universities are working on relevant issues.

SATW is planning a round table in early 2024 to discuss the various industrially relevant technological developments and to formulate a basis for defossilization without side effects.

Are you interested in the topic? Then contact us!

Hans‐Peter Meyer, Expertinova AG, Head Scientific Advisory Board SATW