Comparision of Different Raw Densities and Board Thicknesses in the Production of Enzymatically Bonded Fiberboards

Abstract

Reducing CO 2 emissions for the long term is an important issue in countering climate change. For this reason, the use of renewable construction materials inter alia wood-based materials is becoming increasingly important. Wood based materials often depend on petrochemical-based binding agents, most of which contain and emit formaldehyde. This causes environmental and health-related difficulties that could be rectified by avoiding the utilization of these adhesives. For this purpose, enzymatically bonded medium-density fiberboards (MDF) with a targeted raw density of 650 kg/m³ and 750 kg/m³ and high-density fiberboards (HDF) with a density of 900 kg/m³ were produced in different thicknesses. Laccase-Mediator-System (LMS) was applied to manufacture the boards and to compare them to those glued with UF and inactivated laccase, respectively. These panels were tested in terms of their physical technical properties, such as internal bond strength (IB), modulus of rupture (MOR) and thickness swelling (TS) after 24 h immersion. The aim was to show the correlation between density and these properties for fiberboards bonded this way. Most panels meet the requirements of the European standard when LMS and UF-resin were used. The possibility to produce fiberboards bonded with alternative bonding agents opens up the way to alternative, innovative, healthy and environmental-friendly wood based products.

Enzymatic Oxidation of Ca-Lignosulfonate and Kraft Lignin in Different Lignin-Laccase-Mediator-Systems and MDF Production

“…Similar or slightly improved board qualities were achieved under addition of either enzyme, without or, in LMS, with DMP (Table 2). Application of the LMS compared to solely laccases in this study improved TS and MOR (Table 2), comparable to what was previously reported in LMS-MDF production for Novozym 51003 and mediator HBA (Euring et al, 2011;Kirsch et al, 2016;Kirsch et al, 2017).…”

Effect of Common Metal Ions and Anions on Laccase Catalysis of Guaiacol and Lignocellulosic Fiber

“…The pretreatment of wood with laccase can reduce the amount of adhesive used during the processing of fiberboard. Thus, laccase is useful for the production of environmentally friendly woodbased panels with high hardness and low formaldehyde release (Nasir et al 2013;Kirsch et al 2017). In the paper-making industry, laccase is used for the bio-bleaching of paper pulp through laccase-mediator systems or a combination of laccase and other enzymes (Fillat et al 2010;Singh et al 2015).…”