Recent technological developments in the electro-reduction of carbon dioxide to formic acid, a valuable chemical with possible application in the steel pickling process, may offer an alternative to expensive large scale carbon capture and storage operations.

With the inauguration of President Barack Obama, the United States will soon follow in the footsteps of the European Union by introducing measures to reduce greenhouse gas emissions 80 percent by 2050. Obama's plan includes the introduction of a federal cap and trade system in which the government would set limits on carbon emissions by power plants, factories and other installations. Those who emit more carbon dioxide than the prescribed limit will be allowed to buy or trade permits with those that emit less. Further, Obama vows to allot $15 billion each year to stimulate private sector efforts toward a clean energy future.

Essential to industrial development, the steel industry will play a vital role in the expansion of alternative technologies including wind, solar and the production of fuel efficient vehicles. For an industry that currently emits 4% of the world's total greenhouse gas emissions, implementation of a carbon cap and trade system would come as a big blow. Although improvements in efficiency have dramatically decreased the industry's greenhouse gas emissions they remain a staggering 1.7 tons of carbon dioxide released per ton of steel produced. Global steel output is about 1.3 billion tons per year. Scientific advancements in carbon removal and conversion techniques are therefore paramount.

A great deal of emphasis has been placed on carbon capture and storage (CCS) as a way to deal with high carbon dioxide emissions. Carbon capture and storage is a broad term used to describe technologies that will capture carbon dioxide from point sources and store it in deep geological formations, in deep ocean masses, or as mineral carbonates. The processes involved in CCS have been demonstrated in other industrial applications, so it will likely be one part of the global solution. So far however, the associated costs and environmental risks have prohibited substantial commercial applications.

In light of the economic, technical and legal challenges facing the large-scale deployment of CCS, scientists are exploring innovative strategies to convert carbon dioxide into valuable fuels and chemicals. By turning a waste product into a commodity, researchers are hoping to provide a financial incentive for companies to begin the transformation to clean technologies.

Originating at the University of British Columbia, a new technology named ERC (the electro-reduction of carbon dioxide) aims to take CO₂ directly from blast furnaces and convert it to formic acid, a valuable chemical with many industrial applications. Although the ERC process is not limited to use in the steel industry, a patented technology exists that claims the advantages of formic acid over the commonly used mineral acids for steel pickling. Such technology could provide a cyclical industrial benefit and an economic incentive for industry to take the next step toward CO₂ mitigation.

Hydrochloric acid is currently used extensively in the steel pickling process to clean the oxidized surface of hot-rolled steel during the manufacturing process. It is an aggressive, non-biodegradable acid that corrodes the surrounding plant equipment, can pit the finished steel product, and must be put through an expensive regeneration or neutralization process before it can be reused or released into the environment.

Formic acid has many potential advantages over hydrochloric acid in steel pickling, including but not limited to; producing a better product quality, the ability to be re-used from the spent solution to provide an easy, cost effective recycling process and the fact that it is non-toxic and bio-degradable. The ERC process also produces oxygen as a byproduct which can be used in the blast furnace to increase iron production.

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