Fiksacija pripravkov na osnovi bakra in etanolamina v lesu pri različnih temperaturah : diplomsko delo (visokošolski strokovni študij)

Karlo, Darko (author), Humar, Miha (mentor), Petrič, Marko (reviewer)

Bakrovi zaščitni pripravki so učinkoviti in zelo razširjeni fungicidi. Njihova poglavitna slabost je slaba vezava v les. Ta lastnost omejuje uporabo zaščitenega lesa tam, kjer lahko prihaja do izpiranja aktivnih komponent iz lesa. Fiksacijo bakrovih učinkovin lahko močno izboljšamo z dodajanjem aminov in karboksilnih kislin. Raziskovali smo vpliv povišane temperature na vezavo baker-etanolaminskih pripravkov v les. Smrekove vzorce smo, s postopkom polnih celic impregnirali s tremi različnimi kombinacijami in koncentracijami zaščitnih pripravkov na osnovi bakra, etanolamina, oktanojske kisline, kvartarnih amonijevih spojin in bora. Po gravimetrično določenem mokrem navzemu smo impregnirane vzorce sušili pri različnih temperaturah in sicer: 25 °C, 50 °C, 75 °C in 103 °C. Izpiranje smrekovih vzorcev je potekalo v skladu z nekoliko modificirano standardno metodo SIST EN 1250/2. Delež izpranega bakra v izpirkih smo določili z atomsko absorpcijsko spektroskopijo. Ugotovili smo, da povišana temperatura sušenja negativno vpliva na vezavo zaščitnih pripravkov na osnovi bakra in etanolamina v les. Najmanj bakra se je izpralo pri naravno sušenih vzorcih (25 °C), največ pa pri impregniranih, sušenih pri 103 °C, ne glede na sestavo zaščitnega pripravka s katerim smo prepojili les. Verjetno je pri povišanih temperaturah sušenja prišlo do razgradnje lignina, na katerega se je vezalo največ bakra; to se je poznalo v večjem deležu izpranega bakra.

• Language: Slovenian
• Keywords: zaščita lesa, bakrovi pripravki, izpiranje, vezava
• Work type: Undergraduate thesis
• Typology: 2.11 - Undergraduate Thesis
• Organization: BF - Biotechnical Faculty
• Place of publishing: Ljubljana
• Publisher: [D. Karlo]
• Year: 2006
• Number of pages: VIII, 33 f.
• PID: 20.500.12556/RUL-150
• UDC: 630*841.1
• COBISS.SI-ID: 1447305
• Publication date in RUL: 11.07.2014

Secondary language

• Language: English
• Title: Fixation of copper-ethanolamine based wood preservatives into wood at different temperatures : graduation thesis (higher professional studies)

Abstract

Copper based preservatives are very effective and frequently used fungicides. However, their most important disadvantage is low fixation in wood, decreasing possibilities of use of copper impregnated timber, particularly where leaching of active ingredients appears. Fixation of copper can be significantly improved in combination with amines and carboxylic acids. We wanted to elucidate how increased temperature during fixation influenced copper leaching. Therefore, specimens made of Norway spruce were impregnated with 3 different preservatives of 3 various concentrations. Preservative solutions consisted of copper, ethanolamine, octanoic acid, quaternary ammonium compound and boron. After a full cell vacuum treatment, retentions of preservative were determined gravimetrically. Specimens were dried at 25 °C,50 °C, 75 °C and 103 °C. Leaching of the specimens was performed according to the modified standard method SIST EN 1250/2. Percentage of leached copper in leachates was determined using atomic absorption spectroscopy.The results showed that the highest copper fixation was determined at specimens dried at low temperatures (25 °C), and the lowest one at 103 °C despite of preservative solution used. We believe that higher temperatures caused depolymerisation of lignin due to the presence of ethanolamine, and therefore more prominent copper leaching.

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