TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Process: In the process, further chemicals including at least one active chemical (oxidative agents, catalysts, alkalis and acids, preferably sodium hydroxide, hydrogen peroxide, hydrogen peroxide mixed with cobalt, sulfuric acid or sodium persulfate) are added into the biomass mixture prior to compacting, preferably by spraying, in dry form or in a concentrated solution. The biomass is pressed through the openings of the compactor for: 1-10 times, preferably 1-2 times, or optionally 2-10 times, or even 5-20 times; or more than one time, using sequential compactors. The compacting takes place by pressing the biomass against a perforated pan plate using the rollers of a roller mill, thus the biomass is degraded and fibrillated, and passes through the openings of the pan plate, and optionally repeating the compacting procedure at least one time. The temperature of the biomass is increased to above room temperature during the compacting, to a maximum temperature of 70 degrees C. A transient increased pressure, and shear and elongational deformations are created in the biomass-compactor system, by subjecting the biomass mixture to the compacting. The compacting step is followed by a step of washing the optionally added chemicals off the compacted biomass, preferably using hot water, followed by filtering. EXAMPLE - Lignocellulose biomass based on various lignocellulosic raw materials was optionally first chemically impregnated with a chemical solution (25% sodium hydroxide, 5% sodium persulfate, 5% hydrogen peroxide and cobalt, 5% hydrogen peroxide and 10% sulfuric acid) by spraying the chemical into the biomass in a Forberg-type mixer. Subsequently, the optionally chemically treated biomass was pressed 1-10 times through the e-compactor of F120106340, without the addition of further solvent. Thus, the particle size of the material was decreased, the material surface was fibrillated and at the same time the material was warmed up from room temperature to 50 degrees C. Subsequently, the further chemical of the optional chemical treatment was washed with hot water and filtered in a Buchner funnel to remove excess chemicals and all soluble substances.