Vpliv vrednosti pH baker-etanolaminskih zaščitnih pripravkov na izpiranje : diplomsko delo (visokošolski strokovni študij)

Pučko, Andrej (author), Humar, Miha (mentor), Petrič, Marko (reviewer)

Bakrove spojine so učinkoviti in zelo razširjeni fungicidi. Nezadostna fiksacija omejuje uporabo zaščitenega lesa v okoljih, kjer lahko pride do izpiranja aktivnih komponent. Vezavo bakrovih soli v les so v preteklosti reševali z dodajanjem kromovih spojin, danes pa se uveljavlja etanolamin. Z željo izboljšati vezavo baker-etanolaminskih pripravkov smo raziskali vpliv različnih pH vrednosti pripravkov na vezavo zaščitnih sredstev v les. Smrekove vzorce smo po postopku polnih celic impregnirali s 3 različnimi kombinacijami in 2 različnima koncentracijama zaščitnih pripravkov na osnovi bakra, etanolamina, oktanojske kisline, kvartarnih amonijevih spojin in bora. Impregnirane vzorce smo 4 tedne sušili, nato pa izprali po standardni metodi SIST EN 1250/2. Delež izpranega bakra v izpirkih smo določili z atomsko absorpcijsko spektroskopijo. Ugotovili smo, da se je pri vzorcih, zaščitenih z raztopino nižje koncentracije (cCu = 0,1 %), izpral manjši delež bakra kot pri vzorcih, ki so bili prepojeni z zaščitnim pripravkom višje koncentracije (cCu= 0,5 %). Poleg tega je na vezavo baker-etanolaminskih pripravkov vplivala tudi vrednost pH. Boljšo vezavo baker-etanolaminskih pripravkov smo ugotovili pri vzorcih, ki so bili impregnirani s pripravki z nižjimi, manj bazičnimi vrednostmi pH.

• Language: Slovenian
• Keywords: zaščita lesa, bakrovi pripravki, izpiranje, vezava, smrekovina
• Work type: Undergraduate thesis
• Typology: 2.11 - Undergraduate Thesis
• Organization: BF - Biotechnical Faculty
• Place of publishing: Ljubljana
• Publisher: [A. Pučko]
• Year: 2007
• Number of pages: VIII, 53 f.
• PID: 20.500.12556/RUL-228
• UDC: 630*841
• COBISS.SI-ID: 1542025
• Publication date in RUL: 11.07.2014

Secondary language

• Language: English
• Title: Influence of pH value of copper ethanolamine based wood preservatives on leaching : graduation thesis (higher professional studies)

Abstract

The most important disadvantage of copper based preservatives is low copper fixation on wood components. This is an important drawback, when impregnated wood is used in conditions where leaching of active components is possible. Copper fixation used to be improved with the addition of chromium compounds. Nowadays, it is mainly combined with ethanolamine and octanoic acid. It has already been proven that ethanolamine reacts with wood and copper, resulting in improved Cu fixation. On the other hand, octanoic acid has hydrophobic mode of action. In order to optimize the composition of copper-ethanolamine based wood preservative, influence of pH value on copper leaching was examined. To elucidate those questions, specimens made of Norway spruce were impregnated with different aqueous solutions on the basis of copper, ethanolamine, octanoic acid, quaternary ammonium compounds and boron. Leaching was performed according to the modified standard procedure SIST EN 1250/2. Copper content in leachates was determined using atomic absorbtion spectroscopy. Specimens impregnated with the solutions of lower copper concentration (cCu = 0.1 %) were less prone to leaching than the ones impregnated with specimens of higher concentration (cCu = 0.5 %). Besides that, pH value of preservative solution has significant influence on copper fixation as well. In general, the best fixation was determined at specimens impregnated with copper-ethanolamine solutions of the lowest, the least alkaline pH values.

• Keywords: wood preservation, copper based preservatives, leaching, fixation, spruce wood