Učinci katalizatora na modul loma i kemijsku strukturu toplinski obrađenog drva

Heat treatment process, which is widely used in the wood industry, has shown some negative effects on the mechanical strength of wood. The objective of this study was to investigate the effects of catalysts on the modulus of rupture (MOR), mass loss and chemical structure of heat–treated Scotch pine (Pinus sylvestris L.) samples. For this purpose, some catalysts (50 % NaOH and 47 % KOH solutions, solid KOH) were added to the heat treatment process. Heat treatment experiments were performed under the nitrogen atmosphere at the temperature of 212 °C for 2 h. The MOR and chemical changes monitored by FT-IR spectra were then examined for the test groups. According to the results of this study, the use of commercial solid potassium hydroxide (KOH) in heat treatment decreased the degree of strength loss and mass loss of heat-treated wood. The strength (MOR) loss of samples heat-treated in the presence of potassium hydroxide was found to be only 5.4 %, while the strength loss in non-catalytic treatment was found to be 12.5 %.Proces toplinske obrade, koji se često primjenjuje u drvnoj industriji, pokazao je neke negativne učinke na mehaničku čvrstoću drva. Cilj ove studije bio je ispitati učinke katalizatora na modul loma (MOR), gubitak mase i kemijsku strukturu uzoraka toplinski obrađenog drva običnog bora (Pinus sylvestris L.). S tom namjerom u procesu toplinske obrade drva primijenjeni su katalizatori (50-postotna otopina NaOH i 47-postotna otopina KOH te kruti KOH). Eksperimentalna toplinska obrada drva provedena je u atmosferi dušika, pri temperaturi 212 °C tijekom 2 h. Modul loma i kemijske promjene praćene na spektrima FT-IR za odabrane su skupine uzoraka analizirani. Rezultati studije pokazali su da se primjenom komercijalnoga krutog kalijeva hidroksida (KOH) kao katalizatora pri toplinskoj obradi drva gubitak čvrstoće i gubitak mase toplinski obrađenog drva smanjuju. Utvrđeno je da je gubitak čvrstoće (MOR) uzoraka obrađivanih toplinom uz prisutnost kalijeva hidroksida samo 5,4 %, a gubitak čvrstoće u nekatalitičkom je tretmanu bio 12,5 %