Utilization of lignosulfonates to obtain composite construction materials

When cellulose is obtained by the sulfite method, waste cooking solutions are formed-sulfite liquors containing lignosulfonates and their derivatives, the processing and disposal of which is a complex environmental problem for the pulp and paper industry. Lignosulfonates practically do not undergo biological destruction, therefore, the discharge of liquors into the industrial sewerage system leads to disruption of the biological treatment facilities and deterioration of the sanitary and hygienic state of water bodies. The main way of using waste liquors is their evaporation and/or drying to obtain technical lignosulfonates, which are used as a raw material in various industries. However, the demand for products is well below the production of lignosulfonates, resulting in the accumulation of highly hazardous waste. In this regard, it is important to expand the use of lignosulfonates with the production of marketable products. At present, the pace of construction is increasing in Russia, and various types of derivative materials are widely used in the production of building composite materials, including lignosulfonates, which can be a promising source of raw material in the production of environmentally friendly composite materials. The possibility of using powdered lignosulfonates in composite materials using low toxicity ED-20 epoxy resin as a binder was studied. The conducted studies show the possibility of obtaining composite materials based on lignosulfonates and the epoxy resin ED-20 as a binder. With a proportion of lignosulfonates 40%, the resulting composite effect is manifested by the physical and mechanical properties: water absorption - 8.2%; surface strength - 9.0 MPa; total stress during compression - 45.0 MPa; total bending stress - 23.7 MPa. A comparative analysis was carried out, which showed that, by inheritance, the characteristics are manifested in work that is not inferior to industrial samples of chipboard and wood-epoxy boards. The production of lignoepoxy materials is characterized by a higher service life, corrosion resistance and can compete with the production of industrial analogues.