Effective Recovery of Pulp Waste in the Innovative Production of Environmentally Acceptable Wood Composites

Abstract

However, as a result of efforts to improve the environment, while maintaining the required qualitative characteristics, global developments in the field of wood materials (as raw materials of the 21st century) have led to the development of new or effective modifications of existing technologies, focusing on reducing the emission of formaldehyde and other toxic components in polycondensation adhesives applied to the preparation of composite wood materials. The suggested problem means reciprocal replacement of the toxic components of currently produced polycondensation adhesives (especially phenol-formaldehyde), e.g. kraft black liquors, which can be isolated as a secondary raw material from the pulp and paper industry in the production of sulphate pulp. Sulphate liquros are characterized by a relatively low reactivity to formaldehyde, thus are requiring their incorporation into the polymeric matrix of mixed lignin-phenol-formaldehyde polycondensate. For this reason, it is necessary to modify the reactivity of the original kraft black liquors by the modification reactions. New methods of processing sulphate liquors are focused only on the use of some components of black liquors or on the production of high-price products, which can be applied economically but especially “eco-friendly” in the preparation of wood composite materials as adhesives. The article deals with the problem of effective utilization waste of kraft black liquor from pulp and paper industry, which are possible apply in various modification treatment as reciprocal replacement of polycondensative adhesives for preparation of wood based composite materials. In our research, we focused on proposal of innovative adhesives mixtures which were applied for production of eco-progressive wood based composite materials with better hygienical properties and significantly reducing the content of toxic formaldehyde in adhesive mixtures.