Chemical Research On Titanic

Her makers said that she was unsinkable, but they were very, very wrong. The year was 1912 when the Titanic tragically sank on her maiden voyage. It was in 1985 that the ship’s remains were finally located off the Grand Banks of Newfoundland. The Titanic now rests 3800 m below the surface in the Atlantic Ocean, and she has some amazing chemical reactions going on around her

The Titanic is corroding and very interesting corrosion products are being discovered. The structure, chemistry and mineralogy of the corrosion products are allowing scientists to gain insight into the geochemistry of iron and other metals that were accidentally introduced into this deep sea environment. Since the Titanic was a brand new ship and she had not even completed her first voyage when she sank, this allows for a well-controlled scientific study.

The most obvious corrosion products on the Titanic are rusticles. They resemble stalactites and can reach lengths of tens of centimetres. The rusticles have a smooth red outer surface made up of iron oxyhydroxide. When a rusticle is broken open the core is a bright orange colour. The needle-like crystals that make up the core are called goethite [-FeO(OH)]>

When a biological activity test was performed it was shown that the rusticles grew in the presence of bacteria. The bacteria are a sulfate-reducing species that grow rapidly under anaerobic (no oxygen) conditions.

There are other unusual forms of corrosion that exist on this magnificent wreck, and these are "rust flows" and "rust flakes". The rust flows are predominantly found on the deck of the ship and successive analysis has lead to the fact that they spread at a rate of 10 cm per year. The rust flakes are very similar in composition to the rusticles. They are a mixture of goethite and lepidocrite, both minerals formed in the presence of iron, and suggest bacterial colonization as well.

The study has shown that biological activity in the sea water plays a very significant role in the corrosion of the Titanic. It is now know that these bacteria are essential for the formation of rapidly spreading rust flows and rusticles.