The CSIC patented a method to transform mercury and store it safely

The past 15 March of this year entered into force the new Community regulation which prohibits the export of liquid mercury and the use of this metal in any industrial process. This ban forces stop all processes that incorporate mercury in stages and to dismantle the facilities to store mercury. It is estimated that in Europe there are hundreds of thousands of tonnes of liquid mercury which will now no longer be used. Spain, one of the first exporters of mercury in Europe, also has significant quantities of this element.

The alternatives open to this waste dangerous are either disposal in a safe place or to processing to eliminate the dangerous component. In any case, the management of this mercury the carried out companies expressly authorised by the EU for this purpose. Storing mercury in liquid form means that it should be relegated to a place of high security, with hermetic tanks to give guarantees against the risk of leakage or misuse. Another option would be to transform this metal into another safe and inert material.

It is what he proposes a team of researchers from the National Center for metallurgical investigations of the CSIC. As explains Felix Lopez, Professor of the Center's research and head of the project, "the patented process allows become mercury sulfide of mercury, which is not dangerous, and integrate it into a sulfur polymer cement".

One very interesting aspect is that the procedure can also be applied to lands contaminated by mercury, that they also pose a significant risk of contamination by leaching. The contaminated land are usually industrial lands that have withstood companies mining, metallurgical, or obtaining of chlorine, among others. They are normally in the same place where came from, and only when that floor is devoted to other uses (construction, recreation, empowerment...) use the emptying of the ground. In that case, the contaminated land are usually store in landfills of security.

The final material obtained is a polymer of black color, with a concentration of mercury of 5-30% by weight, as the case may be, and that can be stored in a landfill without risk of escape of mercury oreven used as paving cement.

Laboratory tests have shown that the new material has a rate of water absorption less than other cements used in paving, and that the loss of mercury by leaching is far below current standards of toxicity. Also, the material is highly resistant to corrosive substances such as alkalis (derived from alkali metals, such as ammonia, ammonium hydroxide, calcium oxide and hydroxide, or peroxides).

The company Mayasa (mines of Almaden and Arrayanes) is negotiating with CSIC license of the procedure for bringing it to market. Mayasa has extensive experience in mining and could become one of the companies authorised by the EU for the management of mercury.

Mercury has been used for years in applications several, such as the manufacture of mirrors, the manufacture of measuring instruments such as thermometers and sphygmomanometers, fluorescent lamps and Sockets. These and other applications have been found increasingly substitutes for mercury. Currently the liquid mercury is generated as waste from the mining of gold and the recycling of batteries, accumulators and thermometers which are withdrawn from the market, among other products.

Mercury pollution has very serious effects on the ecosystem and people, especially if the Mercury comes into contact with the water, where it becomes methylmercury, very toxic, impossible to remove and that accumulates in marine organisms. High levels of mercury and methylmercury exposure severely damages the nervous system, brain and kidneys, and has serious effects on the formation of the fetus.