Copper compounds are effective wood preservatives, since there are no other equally protection found on the market. CCB (copper, chrome, boron) is one of the best-known protection agents. Yet chrome used as a binding agent is very much disputed. Currently equally effective substitutes are being sought. Recent research has shown that copper is efficiently binding in combination with ethanolamine acid or octanoic acid. Various types of water coming into direct contact with wood definitely influence the leaching of copper from wood. Hence various types of water were used in the tests, i.e. sea water, fluvial water, tap water, distilled and simulated marsh water. Spruce (Picea abies) wood samples were impregnated according to the full cell treatment, and with different types of protection agents. After binding, the samples were leached according to the modified standard procedure SIST ENV 1250/2. Atomic absorption spectroscopy was used to determine the amount of copper in leachates. The tests showed established that the amount of copper leached varies according to different types of water. Waters having a higher pH-value resulted in more prominent leaching. The simulated marsh water caused the highest copper leaching. Despite of low pH value of leaching solution, composition of preservative solution influence copper fixation as well. The best fixation was determined at wood treated with copper-chromium based solution and the lowest one at the ones treated with copper, ethanolamine, quaternary ammonium compound, octanoic and boron.
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