Open AccessOptimization of the Hot-Pressing Regime in the Production of Eco-Friendly Fibreboards Bonded with Hydrolysis Lignin
Author(s) -
Ivo Valchev,
Yvailo Yordanov,
Viktor Savov,
Petar Antov
Publication year - 2021
Publication title -
periodica polytechnica. chemical engineering
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.322
H-Index - 19
eISSN - 1587-3765
pISSN - 0324-5853
DOI - 10.3311/ppch.18284
Subject(s) - lignin , adhesive , pressing , hydrolysis , hot pressing , environmentally friendly , softening point , phenol formaldehyde resin , materials science , formaldehyde , softening , phenol , composite material , pulp and paper industry , chemistry , chemical engineering , organic chemistry , ecology , layer (electronics) , engineering , biology
This research was aimed at studying the potential of using residual lignin from acid hydrolysis as a binder in manufacturing eco-friendly, dry-process fibreboards. For that purpose, a modification of the adhesive system and hot-pressing regime was conducted. The adhesive system applied was composed of 2 % phenol-formaldehyde (PF) resin and 10 % hydrolysis lignin (based on the dry fibres). The PF resin does not only act as a binder but generally contributes to the even distribution and good retention of the main binder – hydrolysis lignin. A specific hot-pressing cycle was used. In the first stage, the pressure was 1.0 MPa, followed by an increased pressure of 4.0 MPa, and subsequent cooling. The purpose of the initial lower pressure was softening the lignin and reduction of the material moisture content. The effect of the second stage of hot-pressing on the properties of eco-friendly fibreboards was investigated. It was determined that the fibreboards produced with 2 % PF resin and 10 % hydrolysis lignin have similar physical and mechanical properties to those of the control panels, produced with 10 % PF resin at a standard hot-pressing cycle. The findings of this work demonstrate that residual hydrolysis lignin can be effectively utilized as a binder in the production of eco-friendly, dry-process fibreboards with acceptable physical and mechanical properties.