Precipitacija bakrovih soli v lesu za učinkovito zaščito pred glivnim razkrojem

Švikart, Jure (author), Humar, Miha (mentor), Levanič, Jaka (comentor)

Zaradi toksičnosti bakrovih spojin smo želeli z eksperimentom najti alternativo, ki je manj strupena, ima dobre zaščitne lastnosti in se iz lesa ne izpira. Vzorce rdečega bora smo zaščitili na tri različne načine. Vzorce smo zaščitili s 0,5 % suspenzijo bakrovega karbonata, 1 % suspenzijo bakrovega karbonata, 0,5 % koncentracijo bakrovega sulfata, 1 % koncentracijo bakrovega karbonata, 0,5 % koncentracijo bakrovega sulfata z dodatno impregnacijo z natrijevim karbonatom, ter 1 % koncentracijo bakrovega sulfata z dodatno impregnacijo z natrijevim karbonatom. V reakciji med bakrovim sulfatom in natrijevim karbonatom se tvori v vodi praktično netopen bazični bakrov karbonat, ki naj bi deloval fungicidno. Na vzorcih smo opravili preizkus izpiranja po standardu EN84, ter preizkus učinkovitosti zaščite po standardu EN113 z glivama Coniophora puteana in Gloeophyllum trabeum. Rezultati pri izpiranju so pokazali, da so vzorci, ki so bili dvostopenjsko impregnirani, med izpiranjem izgubili bistveno manj bakra kot vzorci zaščiteni le z bakrovim sulfatom. Pri vzorcih zaščitenih s suspenzijo bakrovega karbonata, baker ni penetriral v les, zato se je ta rešitev izkazala za neučinkovito. Rezultati preizkusa po EN 113 pa so pokazali, da je pri primerjavi enakih koncentracij bakra za glivo Gloeophillum trabeum najboljša zaščita z dvostopenjsko impregnacijo, na drugem mestu je zaščita z bakrovim sulfatom, najslabšo zaščito pa je nudil suspendiran bakrov karbonat, ki ni dobro penetriral v les. Pri glivi Coniophora puteana je bila dvostopenjska impregnacija bolj učinkovita le pri 1 % koncentraciji bakra, pri 0,5 % koncentraciji je bila zaščita zelo slaba, zaščita z bakrovim sulfatom je bila nekoliko boljša od dvostopenjske impregnacije, zaščita s supendiranim bakrovim karbonatom je bila najmanj učinkovita.

• Language: Slovenian
• Keywords: les, zaščita lesa, baker, nanodelci, impregnacija
• Work type: Bachelor thesis/paper
• Typology: 2.11 - Undergraduate Thesis
• Organization: BF - Biotechnical Faculty
• Publisher: [J. Švikart]
• Year: 2025
• PID: 20.500.12556/RUL-172876
• UDC: 630*841.1
• COBISS.SI-ID: 248277763
• Publication date in RUL: 12.09.2025

Secondary language

• Language: English
• Title: Precipitation of copper salts in timber for efficient preservation of wood against fungal decay

Abstract

Due to the toxicity of copper compounds, we aimed to find an alternative through experimentation that is less toxic, has good protective properties, and does not leach out of the wood. We treated samples of Scots pine in three different ways. The samples were treated with a 0.5% suspension of copper carbonate, a 1% suspension of copper carbonate, a 0.5% solution of copper sulfate, a 1% solution of copper carbonate, a 0.5% solution of copper sulfate with additional impregnation using sodium carbonate, and a 1% solution of copper sulfate with additional impregnation using sodium carbonate. In the reaction between copper sulfate and sodium carbonate, a basic copper carbonate is formed, which is practically insoluble in water and is expected to have fungicidal properties. The samples were subjected to a leaching test according to the EN84 standard and a protective efficacy test according to the EN113 standard, using the fungi Coniophora puteana and Gloeophyllum trabeum. The leaching test results showed that the samples that underwent two-step impregnation lost significantly less copper during leaching compared to the samples treated only with copper sulfate. In the case of the samples treated with a copper carbonate suspension, the copper did not penetrate the wood, making this treatment ineffective. The EN113 test results showed that for Gloeophyllum trabeum, the best protection at equal copper concentrations was achieved with the two-step impregnation, followed by copper sulfate treatment, while the least effective was the copper carbonate suspension, due to poor penetration into the wood. For Coniophora puteana, the two-step impregnation was more effective only at a 1% copper concentration; at 0.5%, the protection was very poor. Treatment with copper sulfate was slightly more effective than the two-step impregnation, and the copper carbonate suspension was again the least effective.

• Keywords: wood, wood protection, copper, nanoparticles, impregnation