Carbon Capture and Utilisation

Carbon capture and utilisation (CCU) involves using waste CO2 from industrial processes as a raw material in the manufacture of fuels, chemicals and materials. It also has the potential to utilise CO2 extracted from the atmosphere.

Carbon capture and storage (CCS) is a more familiar notion‑‑see the article on CCS on this website). However, CCU has the advantage that it has the potential to produce commercially valuable products in the process of using up a gas that most climate scientists agree is a major contributor to global warming. The carbon atoms from the CO2 end up in the molecules of the manufactured products. The article "Use of plants and microbes for the production of fuels and chemicals" gives examples of CCU in describing how plants and algae may be used in this regard.

A flavour of the kind of ideas involved can be gained through exploring the website of the organisation CO2 Chem. This is a network of academics, industrialists and policy makers engaged in researching and developing approaches for the manufacture of fuels and chemicals from CO2. From their website their report Carbon Capture and Utilisation in the Green Economy can be accessed. A summary report and a full report are presented—the latter for those interested in chemical detail.

What is interesting in the report from a regional perspective is the description of the work of two north east companies. The first involves AFS Ltd, a Darlington-registered company, which is developing a process to produce liquid transport fuel using CO2 and water from the atmosphere. Fuel manufactured in this way neutralises the emission of CO2 from its combustion in transport vehicles: i.e. there is no net production of CO2 in fuel manufactured and combusted thus.

The second concerns work by a group at Newcastle University, resulting in the establishment of a spin-out company‑‑Dymeryx Ltd. Catalysts (chemicals that speed up chemical processes) have been developed that enable CO2 in the waste gas from fossil-fuel-fired electricity generation to be used in manufacturing cyclic carbonates. These chemicals have diverse applications, including the production of the plastics, polycarbonate and polyurethane, which have many uses, including in electrical and electronic components and in making construction materials. A major advantage of the catalysts developed at Newcastle is in allowing the use of the highly impure CO2 that is the waste gas emanating from fossil-fuelled power stations. This gas contains impurities (e.g. oxides of sulphur and nitrogen) that would normally be expected to disable catalytic activity. The relatively low pressures and temperatures required (and therefore reduced energy requirements) are of further advantage. Coupling reactors that make materials with fossil-fuel power generation thus has the potential to neutralise the CO2 that would otherwise be emitted from power generation. One asks whether a reactor could also be designed for the manufacture of cyclic carbonates utilising CO2 extracted from the atmosphere. Such an innovation would have the potential to actually decrease atmospheric CO2 levels.

Alan Myers
9 January 2012