Scienziato testa Biodiesel al microscopio

Methanol from natural gas and CO₂: a circular energy vector

We are developing more efficient systems to convert natural gas and carbon dioxide into methanol.

Technology

We are concentrating on methanol as an intermediate for the chemical industry, as a fuel and especially as an alternative energy vector to hydrogen. We have various ongoing projects in this area, mainly concerning technologies to obtain methanol more efficiently from methane and from non-recyclable waste. The first involves Short Contact Time - Catalytic Partial Oxidation (SCT-CPO) technology. Regarding the second, we launched the “Waste to Methanol” pilot project at our Livorno refinery, where we obtain methanol from plasmix and Solid Recovered Fuel (SRF). Looking ahead, we are examining with interest the feasibility of obtaining it directly from the hydrogenation of CO2; although the process is energy intensive, these needs can be met with renewable energy.

Context

Methanol offers great opportunities for the energy and chemical industries, and demand for it on international markets is constantly growing. The simplest alcohol, its most valued property is its ability to transport energy efficiently, making it an excellent energy vector. Unlike an energy source found ready-made in nature, a vector is “created”, storing energy in its chemical bonds that enables it to carry this energy easily and release it upon use. Methanol is highly versatile due to certain specific properties: it is liquid at room temperature, soluble in water and biodegradable. Methanol can be obtained from methane and is easier to transport than a gas, which requires major infrastructure such as gas pipelines, carrier ships, liquefaction plants, transport and regasification plants. Furthermore, methanol can be used directly as a fuel for road or sea vehicles or to generate electricity, with a net reduction in pollutants such as NOx, SOx and particulates. Additional benefits derive from its use in well-established production cycles in the chemical industry, such as the manufacture of plastics, clothing and furnishings.

Technological challenge

We are undergoing a transition from energy derived from fossil fuels to energy from renewable sources; natural gas is an energy source with a lower carbon content, meaning fewer CO2 emissions, without compromising on the energy generated. Methane, the main component of natural gas, is thus becoming a key element in the present energy paradigm and one of the main sources for obtaining methanol, with syngas as an intermediary stage. Short Contact Time - Catalytic Partial Oxidation (SCT-CPO) is employed at this stage: this innovative technology has a high energy efficiency and compact design, making it versatile and installable directly on off-shore platforms or ships. At this point, the syngas produced directly from natural gas can be used for synthesising methanol, or for other production cycles, with increased efficiency and reduced CO2 emissions. The Waste to Methanol project is currently being set up, and involves the installation at our Livorno refinery of a plant for producing methanol from Solid Recovered Fuel(SRF), which is obtained from dry, non-hazardous municipal waste and plasmix (non-recyclable plastics). The reaction takes place in a sealed environment, meaning no direct emissions, and at a sufficiently high temperature to prevent the formation of dioxins or other toxic organic compounds, leading to the vitrification of the inert material in the feedstock. Emissions are notably reduced compared to those from waste-to-energy conversion, and mostly comprise high-purity CO2, which can be made available for other applications. The challenge is to obtain methanol directly from the reduction of CO2 with hydrogen generated from the electrolysis of water using renewable energy, giving rise to a carbon-neutral production cycle.

Industrial integration

The methanol cycle is ideal for integration into our operations since it includes the use, as a raw material, of products and by-products from the energy industry, such as methane from natural gas reserves and associated petroleum gas. A methanol production process that uses CO2 is of even greater interest as it can provide a way of reusing the CO2 generated in Oil & Gas operations and other industrial activities. Additionally, because it can be directly used in combustion engines, methanol can be distributed for consumption: as a fuel for ships and power plants and as an additive in fuel for haulage. With FCA, we have developed a new A20 Fuel, which has a high-octane number and low emissions because of its alcohol content: 15% methanol and 5% ethanol. A trial with five Fiat 500s from the Eni Enjoy fleet in Milan confirmed the reduced emissions. As a liquid, once produced, methanol can be stored and transported far more easily, and potentially sold on global markets.

Environmental impact

Methanol is once again a focus of expectations in the energy sector, and, indeed, George Olah, professor at the University of Southern California and Nobel Laureate in Chemistry 1994, speaks of the “methanol economy”. Its intrinsic properties and the type of industrial processes used to produce it mean this alcohol can generate virtuous production cycles in line with the principles of the circular economy. Producing methanol from the methane or CO2 associated with fossil fuel deposits, for example, contributes to the carbon neutrality of many energy-industry processes. Using it in new concept engines and integrating it into a specific infrastructure network, we can foresee, in the not too distant future, obtaining it from carbon dioxide collected on-board vehicles and then delivered to service stations, creating a low-emission production cycle for haulage fuels.

Sul Gas Naturale - Energy Transition | Eni Video Channel

Sul Gas Naturale - Energy Transition | Eni Video Channel